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Editor’s Choice Articles

Editor’s Choice articles are based on recommendations by the scientific editors of MDPI journals from around the world. Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to readers, or important in the respective research area. The aim is to provide a snapshot of some of the most exciting work published in the various research areas of the journal.

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13 pages, 1789 KiB  
Review
The Climate Change Crisis: A Review of Its Causes and Possible Responses
by Albert J. Gabric
Atmosphere 2023, 14(7), 1081; https://doi.org/10.3390/atmos14071081 - 27 Jun 2023
Cited by 11 | Viewed by 7457
Abstract
Anthropogenic climate change (ACC) has evolved into a set of crises due to society’s deep economic dependency on fossil fuels. These multiple crises have been well documented and span diverse ecological, human health and economic settings. Given the scale and breadth of CC [...] Read more.
Anthropogenic climate change (ACC) has evolved into a set of crises due to society’s deep economic dependency on fossil fuels. These multiple crises have been well documented and span diverse ecological, human health and economic settings. Given the scale and breadth of CC impacts, expert labeling of the issues has gradually changed from the somewhat benign sounding “global warming” to the more frightening description of a “climate emergency”. Notwithstanding calls for transformative societal change, serious attempts to confront ACC have been hampered by decades of government policy inaction, various scientific debates, political conservatism and denial and public ignorance or apathy. Meanwhile, atmospheric greenhouse gas concentrations have increased inexorably and show no sign of plateauing. The impacts of ACC are becoming evident sooner than expected, and projections for the future of the planet’s ecosystems and the human population which depends on them are dire. Proposals to geoengineer the climate are currently being hotly debated within the scientific community but may prove to be a last resort if the impacts of unmitigated warming become even more severe. Full article
(This article belongs to the Section Climatology)
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26 pages, 23523 KiB  
Article
Study on the Layout of Public Space in Multistory Settlements Based on Outdoor Thermal Environment in Hot-Summer and Cold-Winter Regions of China
by Qian Ma, Lei Shi, Jiaqi Shi, Simian Liu, Mengjia Chen and Fupeng Zhang
Atmosphere 2023, 14(7), 1070; https://doi.org/10.3390/atmos14071070 - 25 Jun 2023
Cited by 1 | Viewed by 1377
Abstract
Residential public spaces are closely intertwined with residents’ lives as the outdoor thermal environment significantly influences the comfort and safety of outdoor activities. However, in modern designs, factors such as forms, aesthetics and functionalities often take precedence, resulting in the neglect of the [...] Read more.
Residential public spaces are closely intertwined with residents’ lives as the outdoor thermal environment significantly influences the comfort and safety of outdoor activities. However, in modern designs, factors such as forms, aesthetics and functionalities often take precedence, resulting in the neglect of the microclimate of the settlement’s public spaces. In this paper, we established a workflow of “parametric simulation-performance simulation-genetic optimization”. By employing the octopus genetic algorithm tool, we conducted experiments on a typical model and set objectives to optimize the winter sunshine duration as well as the thermal comfort during the summer and winter. The results indicated that the average value of the UTCI was optimized for both the summer and winter. This study concludes that altering the layout of public spaces is beneficial for the outdoor microclimate. Additionally, the presence of evenly distributed open node spaces throughout the settlement can improve ventilation in all areas while also protecting it against the winter cold and the dissipation of summer heat. Moreover, it is advisable to position larger public spaces, such as plazas, in the south or southeast. The number of public spaces should gradually decrease in size from the southeast to northwest as this prevents excessive cold winds from traversing in the settlement during the winter. Full article
(This article belongs to the Special Issue Urban Microclimate: Thermal Comfort, Air Quality and Green Building as Drivers of Healthy Urban Design)
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20 pages, 3373 KiB  
Article
Total Electron Content PCA-NN Prediction Model for South-European Middle Latitudes
by Anna Morozova, Teresa Barata, Tatiana Barlyaeva and Ricardo Gafeira
Atmosphere 2023, 14(7), 1058; https://doi.org/10.3390/atmos14071058 - 21 Jun 2023
Viewed by 1316
Abstract
A regression-based model was previously developed to forecast total electron content (TEC) at middle latitudes. We present a more sophisticated model using neural networks (NN) instead of linear regression. This regional model prototype simulates and forecasts TEC variations in relation to space weather [...] Read more.
A regression-based model was previously developed to forecast total electron content (TEC) at middle latitudes. We present a more sophisticated model using neural networks (NN) instead of linear regression. This regional model prototype simulates and forecasts TEC variations in relation to space weather conditions. The development of a prototype consisted of the selection of the best set of predictors, NN architecture, and the length of the input series. Tests made using the data from December 2014 to June 2018 show that the PCA-NN model based on a simple feed-forward NN with a very limited number (up to six) of space weather predictors performs better than the PCA-MRM model that uses up to 27 space weather predictors. The prototype is developed on a TEC series obtained from a GNSS receiver at Lisbon airport and tested on TEC series from three other locations at middle latitudes of the Eastern North Atlantic. Conclusions on the dependence of the forecast quality on longitude and latitude are made. Full article
(This article belongs to the Special Issue Ionospheric and Magnetic Signatures of Space Weather Events at Middle and Low Latitudes: Experimental Studies and Modelling (2nd Edition))
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11 pages, 1662 KiB  
Communication
The Dependence of Gales on Relevant Meteorological Elements in One of the Hottest Regions of China, the Turpan Basin
by Zhiqi Xu, Hao Tang, Xiya Zhang and Haibo Hu
Atmosphere 2023, 14(6), 1051; https://doi.org/10.3390/atmos14061051 - 19 Jun 2023
Viewed by 1208
Abstract
The Turpan Basin is one of the hottest regions in China, with high fire potential. The occurrence of gales could roll over trains as well as spread and expand the fire rapidly, posing adverse effects on traffic and fire protection. Therefore, it is [...] Read more.
The Turpan Basin is one of the hottest regions in China, with high fire potential. The occurrence of gales could roll over trains as well as spread and expand the fire rapidly, posing adverse effects on traffic and fire protection. Therefore, it is important to discuss the frequency and mechanism of gales in Turpan. Based on the observational data of seven stations and ERA5 reanalysis data from 2015 to 2021, this study uses the t-mode principal component analysis using the oblique rotation (T-PCA) method to explore the seasonal differences and related synoptic patterns of gales in the Turpan Basin. The synoptic circulations are divided into nine categories. In types 1, 2, 3, 5, 7 and 9, there are a high-pressure center to the west and a lower-pressure center to the south of Turpan, while in types 4, 6 and 8, there is a strong high-pressure center to the south or northeast of Turpan. When the high-pressure system is located to the west of Turpan, gales are prone to occur, while to the south or northeast, gales seem to be less likely to occur, which is closely related to synoptic patterns and terrain. To the best of our knowledge, this study pioneered the frequency and mechanism of gales in Turpan, which could facilitate gale prevention in the area. Full article
(This article belongs to the Special Issue China Heatwaves)
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19 pages, 22393 KiB  
Article
Research on the Influence Mechanism of Outdoor Wind Environment on Indoor Smoke Exhaust Efficiency in the Super-High-Rise Tower Crown Based on Airpak Simulation
by Tongtong Zhang, Xiaojun Zhou, Zhongsheng Zhang and Fei Qu
Atmosphere 2023, 14(6), 1048; https://doi.org/10.3390/atmos14061048 - 19 Jun 2023
Viewed by 1366
Abstract
The high wind pressure and velocity of the outdoor environment make super-high-rise tower crown space distinct from general tall through space. This segregation causes the crown space to be particularly prone to smoke short-circuiting influenced by the outside wind environment if a fire [...] Read more.
The high wind pressure and velocity of the outdoor environment make super-high-rise tower crown space distinct from general tall through space. This segregation causes the crown space to be particularly prone to smoke short-circuiting influenced by the outside wind environment if a fire occurs indoors, and causes deficient smoke exhaust efficiency in a fire. The goal of this study was to investigate the general principle regarding the effect of the outdoor wind environment on smoke exhaust efficiency of such spaces under the crown space. We measured external wind direction and wind pressure in the smoke exhaust in the tower crown and developed setting plans for the exhaust outlets and make-up air inlet. Airpak was used to create the external wind environment and compare simulations to see if smoke short-circuiting occurred. We analyzed the causes, summarized solutions that did not result in short-circuiting of smoke flow, and made adjustments. We provide an ideal plan for the setting direction and vent velocity of the make-up air inlet and exhaust outlet in the crown spaces of super-tall towers to improve the design of smoke exhaust systems in such spaces. Full article
(This article belongs to the Special Issue Urban Microclimate: Thermal Comfort, Air Quality and Green Building as Drivers of Healthy Urban Design)
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14 pages, 1183 KiB  
Article
A Comparison of Models for the Forecast of Daily Concentration Thresholds of Airborne Fungal Spores
by Andrés M. Vélez-Pereira, Concepción De Linares, Miquel A. Canela and Jordina Belmonte
Atmosphere 2023, 14(6), 1016; https://doi.org/10.3390/atmos14061016 - 13 Jun 2023
Cited by 3 | Viewed by 1566
Abstract
Aerobiological predictive model development is of increasing interest, despite the distribution and variability of data and the limitations of statistical methods making it highly challenging. The use of concentration thresholds and models, where a binary response allows one to establish the occurrence or [...] Read more.
Aerobiological predictive model development is of increasing interest, despite the distribution and variability of data and the limitations of statistical methods making it highly challenging. The use of concentration thresholds and models, where a binary response allows one to establish the occurrence or non-occurrence of the threshold, have been proposed to reduce difficulties. In this paper, we use logistic regression (logit) and regression trees to predict the daily concentration thresholds (low, medium, high, and very high) of six airborne fungal spore taxa (Alternaria, Cladosporium, Agaricus, Ganoderma, Leptosphaeria, and Pleospora) in eight localities in Catalonia (NE Spain) using data from 1995 to 2014. The predictive potential of these models was analyzed through sensitivity and specificity. The models showed similar results regarding the relationship and influence of the meteorological parameters and fungal spores. Ascospores showed a strong relationship with precipitation and basidiospores with minimum temperature, while conidiospores did not indicate any preferences. Sensitivity (true-positive) and specificity (false-positive) presented highly satisfactory validation results for both models in all thresholds, with an average of 73%. However, seeing as logit offers greater precision when attempting to establish the exceedance of a concentration threshold and is easier to apply, it is proposed as the best predictive model. Full article
(This article belongs to the Special Issue Airborne Fungal and Pteridophyte Spores)
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17 pages, 4353 KiB  
Article
Study on An Effective Roadway Watering Scheme for Mitigating Pedestrian Thermal Comfort According to the Street Configuration
by Hideki Takebayashi, Hiroyuki Mori and Ushio Tozawa
Atmosphere 2023, 14(6), 1014; https://doi.org/10.3390/atmos14061014 - 12 Jun 2023
Cited by 2 | Viewed by 1358
Abstract
Continuous measurement of road surface temperature using an infrared camera throughout the summer season was conducted to clarify the duration of surface temperature decrease due to roadway watering according to weather conditions and watering time. Watering during sunny daytime conditions resulted in a [...] Read more.
Continuous measurement of road surface temperature using an infrared camera throughout the summer season was conducted to clarify the duration of surface temperature decrease due to roadway watering according to weather conditions and watering time. Watering during sunny daytime conditions resulted in a maximum reduction in surface temperature of about 10 °C and an average reduction of about 6 °C. The duration of the surface temperature decrease was short (less than 30 min) for sunny days and long (more than 30 min) for cloudy days. On sunny days, if the evaporation rate was faster and the surface temperature decrease was larger, then the duration of the evaporation was shorter. Effective roadway watering plans were investigated according to the street configurations by simulating the thermal environment considering the solar radiation shielding condition of pedestrians on sidewalks. Simulation results in the downtown area of Kobe city indicated that watering the nearby roadways resulted in only 20% and 39% comfort for the northern sidewalks on the east–west road at 10:00 and 16:00, but about 70% comfort for the southern sidewalks and 60–90% comfort for the eastern and western sidewalks. Guiding pedestrians to a shaded sidewalk and then watering the nearby roadway to lower the surface temperature in the sun improves the thermal environment for pedestrians. Full article
(This article belongs to the Special Issue Research on Building Coating for Urban Heat Island Mitigation)
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23 pages, 4680 KiB  
Article
The Role of Neutral Wind Velocity and Its Vertical Component on Predictability of Formation and Localization of Sporadic E (Es)
by Goderdzi G. Didebulidze, Giorgi Dalakishvili, Maya Todua and Lekso Toriashvili
Atmosphere 2023, 14(6), 1008; https://doi.org/10.3390/atmos14061008 - 10 Jun 2023
Cited by 1 | Viewed by 1673
Abstract
The formation and localization of sporadic E (Es) layers predicted by the ion vertical drift velocity and its vertical change in the lower thermosphere during nighttime are shown analytically and by numerical simulations. The consideration of the existence of a minimum negative value [...] Read more.
The formation and localization of sporadic E (Es) layers predicted by the ion vertical drift velocity and its vertical change in the lower thermosphere during nighttime are shown analytically and by numerical simulations. The consideration of the existence of a minimum negative value of the vertical change of the ion vertical drift velocity as a necessary condition of formation of the Es layer and determining ion convergence rate into this layer is extended in case of the presence of vertical wind. Upward vertical wind can shift the convergence regions upward, while downward vertical wind shifts them downward, unlike the cases of the presence of only meridional and zonal winds. It also changes the ion convergence rate compared to the one with just a horizontal wind. It is shown for the first time that the upward constant wind also causes the convergence of ions with the maximum rate in the region where the ion-neutral collision frequency is equal to their cyclotron frequency. While demonstrating the presented theory by numerical simulations, HWM14 data is used for the meridional and zonal wind velocity profiles and the presence of its vertical component is assumed. In this case, in addition to the estimated ion drift velocity and its vertical changes, their initial distribution and ambipolar diffusion also determine the development of ion convergence/divergence processes. For a small magnitude of vertical wind velocity, its significant influence on the ions/electrons behavior is demonstrated, which shows the importance of both tidal wind and wind changes caused by the propagation of atmospheric gravity waves on the formation of the Es layer. In this theoretical research, it is shown that the realistic profile of the wind velocity, which takes into account the vertical component along with its zonal and meridional ones, is important for the prediction of the Es layers formation, as well as regions of ion depletion. Full article
(This article belongs to the Special Issue State-of-the-Art in Gravity Waves and Atmospheric-Ionospheric Physics)
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16 pages, 5372 KiB  
Article
Exploring the Relationship between Geomagnetic Variations and Seismic Energy Release in Proximity to the Vrancea Seismic Zone
by Andrei Mihai, Victorin-Emilian Toader, Iren-Adelina Moldovan and Mircea Radulian
Atmosphere 2023, 14(6), 1005; https://doi.org/10.3390/atmos14061005 - 10 Jun 2023
Viewed by 1527
Abstract
Understanding the seismo–ionospheric coupling mechanism requires a quiet geomagnetic condition, as this represents an ideal situation to detect abnormal variations in the geomagnetic field. In reality, continuous interactions between solar wind and Earth’s magnetosphere create many fluctuations in the geomagnetic field that are [...] Read more.
Understanding the seismo–ionospheric coupling mechanism requires a quiet geomagnetic condition, as this represents an ideal situation to detect abnormal variations in the geomagnetic field. In reality, continuous interactions between solar wind and Earth’s magnetosphere create many fluctuations in the geomagnetic field that are more related to sun–magnetosphere interactions than to seismotectonic causes. A triaxial magnetometer was installed at the Muntele Rosu Observatory near the Vrancea seismic zone in 1996 to measure the local magnetic field. Since 2002, the data have become more consistent, allowing for the representation of long time series. Since then, variations have been observed on the eastern component (By) of the magnetic field, which sometimes overlaps with significant earthquakes. Previous studies have shown that high decreases in amplitude recorded on the By component of the magnetic field measured at Muntele Rosu have been accompanied by higher seismicity, while small decreases have been accompanied by lower seismic energy release. This research analyzes the geomagnetic data collected between September 2002 and May 2008 from two geomagnetic observatories, one located in the proximity of the Vrancea seismic zone and another one situated 120 km away. For each geomagnetic anomaly identified, the daily seismic energy released was plotted logarithmically, along with seismicity and Kp indices. Additionally, the daily seismic energy released was also plotted logarithmically for all earthquakes with Mw ≥3. To identify variations in the By component, datasets recorded at Muntele Rosu (MLR) were compared with those recorded at Surlari National Geomagnetic Observatory (SUA), to discriminate between global magnetic variations associated with solar activity and possible seismo–electromagnetic variations. The standard deviation (SDBy) was calculated for each anomaly recorded on the By component of the magnetic field and compared with the cumulative seismic energy release. To determine if this type of variation was present in other components of the magnetic field, the following ratios were calculated for all data recorded at Muntele Rosu: Bz/Bx, Bz/By, and Bz/BH. The size of the anomalies resulting from the standard deviation measured on the By component (SDBy) partially validates the relationship between the size of the anomalies and the seismic energy release during the anomaly. The relationship between the released seismic energy and the anomaly magnitude is vaguely respected, but these variations seem to follow two patterns. One pattern is described by smooth decreases, and the other pattern involves decreases where the By component varies significantly over short periods, generating decreases/increases in steps. It was noticed that seismic activity is greater for the second pattern. Additionally, using standard deviation measured on the magnetic field represents a great tool to discriminate external magnetic field variations from local, possibly seismo–magnetic variations. Full article
(This article belongs to the Special Issue Ionospheric and Magnetic Signatures of Space Weather Events at Middle and Low Latitudes: Experimental Studies and Modelling (2nd Edition))
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19 pages, 14090 KiB  
Article
Climate Potential for Apple Growing in Norway—Part 1: Zoning of Areas with Heat Conditions Favorable for Apple Growing under Observed Climate Change
by Ana Vuković Vimić, Mirjam Vujadinović Mandić, Milica Fotirić Akšić, Ksenija Vukićević and Mekjell Meland
Atmosphere 2023, 14(6), 993; https://doi.org/10.3390/atmos14060993 - 7 Jun 2023
Cited by 7 | Viewed by 1809
Abstract
Agricultural production is already, and obviously, affected by climate change. Adapting to climate change includes reducing future risks to ensure yield quality and quantity and considers seizing any potential opportunities induced by climate change. In higher latitude areas, such as Norway, cold climate [...] Read more.
Agricultural production is already, and obviously, affected by climate change. Adapting to climate change includes reducing future risks to ensure yield quality and quantity and considers seizing any potential opportunities induced by climate change. In higher latitude areas, such as Norway, cold climate limits the cultivation of fruits. An increase in temperature offers more favorable conditions for fruit production. In this study, using available phenological observations (full blooming) and harvest dates, and meteorological data from the experimental orchard of NIBIO Ullensvang, the minimum heat requirements for growing different apple varieties are determined. Those criteria are used for zoning of the areas with heat favorable conditions for apple growing. Data on six varieties were used, with lower and higher requirements for heat for fruit development (Discovery, Gravenstein, Summerred, Aroma, Rubinstep, and Elstar). High resolution daily temperature data were generated and used for zoning of the areas with heat favorable conditions for apple growing within the selected domain, which includes Western Norway, Southern Norway, Eastern Norway, and the western part of Trøndelag, Mid-Norway. Dynamics of the change in such surfaces was assessed for the period of 1961–2020. The total surface with favorable heat conditions for growing the varieties with lesser requirement for heat increased three times during this period. The growing of more heat-demanding varieties increased from near zero to about 2.5% of the studied land surface. In the period of 2011–2020, surface area with favorable heat conditions for apple growing was almost 27,000 km2, and a surface area of about 4600 km2 can sustain growing of more heat-demanding varieties. The presented results show the increasing potential of the climate of Norway for apple cultivation and highlight the importance of implementation of fruit production planned according to climate change trends, including the assessment of potential risks from climate hazards. However, the methodology for determining heat requirements can be improved by using phenological ripening dates if available, rather than harvest dates which are impacted by human decision. Zoning of areas with the potential of sustainable apple growing requires the use of future climate change assessments and information on land-related features. Full article
(This article belongs to the Section Climatology)
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16 pages, 3723 KiB  
Article
Interferometry Observations of the Gravity Wave Effect on the Sporadic E Layer
by Chane Moges Seid, Ching-Lun Su, Chien-Ya Wang and Yen-Hsyang Chu
Atmosphere 2023, 14(6), 987; https://doi.org/10.3390/atmos14060987 - 6 Jun 2023
Cited by 1 | Viewed by 1297
Abstract
On the basis of interferometry measurement made with the Chung-Li VHF radar, we investigated the effects of upward propagating gravity waves on the spatial structures and dynamic behavior of the 3 m field-aligned irregularities (FAIs) of the sporadic E (Es) layer. The results [...] Read more.
On the basis of interferometry measurement made with the Chung-Li VHF radar, we investigated the effects of upward propagating gravity waves on the spatial structures and dynamic behavior of the 3 m field-aligned irregularities (FAIs) of the sporadic E (Es) layer. The results demonstrate that the quasi-periodic gravity waves oscillating at a dominant wave period of about 46.3 min propagating from east-southeast to west-northwest not only modulated the Es layer but also significantly disturbed the Es layer. Interferometry analysis indicates that the plasma structures associated with gravity wave propagation were in clumpy or plume-like structures, while those not disturbed by the gravity waves were in a thin layer structure that descended over time at a rate of about 2.17 km/h. Observation reveals that the height of a thin Es layer with a thickness of about 2–4 km can be severely modulated by the gravity wave with a height as large as 10 km or more. Moreover, sharply inclined plume-like plasma irregularities with a tilted angle of about 55° or more with respect to the zonal direction were observed. In addition, concave and convex shapes of the Es layer caused by the gravity wave modulations were also found. Some of the wave-generated electric fields were so intense that the corresponding E × B drift velocities of the 3 m Es FAIs approximated 90 m s−1. Most interestingly, sharp Doppler velocity shear as large as 68 m/s/km of the Es FAIs at a height of around 108 km, which bore a strong association with the result of the gravity wave propagation, was provided. The plausible mechanisms responsible for this tremendously large Doppler velocity shear are discussed. Full article
(This article belongs to the Section Upper Atmosphere)
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13 pages, 7066 KiB  
Article
Quantitative Reconstruction of Paleoclimatic Changes in the Late Miocene Eastern Zhejiang Based on Plant Fossils
by Liang Xiao, Jian Wang, Deshuang Ji, Liyan Guo, Xing Wang, Jiaqi Liang, Xiaoyuan Xia, Wenxiu Ren and Xiangchuan Li
Atmosphere 2023, 14(6), 986; https://doi.org/10.3390/atmos14060986 - 6 Jun 2023
Cited by 1 | Viewed by 1643
Abstract
With a series of Cenozoic climate fluctuations, the global paleoclimate shifted from a warm climate to a cold climate, causing Arctic ice caps to be formed. The Late Miocene is a critical time in this transition period, in which the climate was rapidly [...] Read more.
With a series of Cenozoic climate fluctuations, the global paleoclimate shifted from a warm climate to a cold climate, causing Arctic ice caps to be formed. The Late Miocene is a critical time in this transition period, in which the climate was rapidly cooling. Plant fossils from this epoch could be used as ideal indicators for reconstructing climate change throughout this time interval. In this study, plant fossils were collected from the Shengxian Formation in Ninghai and Tiantai of eastern Zhejiang. We divided the fossiliferous strata of the Shengxian Formation into five layers according to different lithology and chronological order, which were named: JHU0, DLX, JHU1, JHUW, and JHU3 from old to new geological times, respectively. We used Leaf Margin Analysis and Climate Leaf Analysis Multivariate Program to reconstruct paleoclimatic changes in eastern Zhejiang during the Late Miocene. The paleoclimatic information of the five stages from old to new times was obtained based on the plant fossils of each layer. The mean annual temperature values in eastern Zhejiang were reconstructed using the Climate Leaf Analysis Multivariate Program and Leaf Margin Analysis at the same time. However, the former mean annual temperature values are lower than the latter values. After comparing the two sets of mean annual temperature data with previously reported values, it is found that the results obtained by Climate Leaf Analysis Multivariate Program are more reliable, whose values are 18.05 °C, 16.03 °C, 17.96 °C, 16.57 °C, and 15.52 °C from old to new times, respectively. Moreover, 11 climatic parameters were reconstructed using the Climate Leaf Analysis Multivariate Program PhysgAsia2 calibration, among which the growing season precipitation was found to be 195.54 cm, 181.25 cm, 207.99 cm, 180.7 cm, and 165.07 cm; while the difference between the coldest and warmest months was found to be 22.14 °C, 23.4 °C, 22.07 °C, 21.36 °C, and 23.37 °C. The relatively low difference between the coldest and warmest months values and the growing season precipitation values during the Late Miocene might be due to a weaker East Asian monsoon system in the Late Miocene than in modern times. Full article
(This article belongs to the Special Issue Paleoclimate Reconstruction)
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19 pages, 6917 KiB  
Article
Ionosphere over Eastern North Atlantic Midlatitudinal Zone during Geomagnetic Storms
by Teresa Barata, Joana Pereira, Manuel Hernández-Pajares, Tatiana Barlyaeva and Anna Morozova
Atmosphere 2023, 14(6), 949; https://doi.org/10.3390/atmos14060949 - 29 May 2023
Cited by 1 | Viewed by 1826
Abstract
The ionospheric response at middle latitudes to geomagnetic storms is not yet very well understood. Total electron content (TEC) variations associated with eight strong geomagnetic storms between 2015 and 2022 obtained from GNSS receivers in the eastern area of the North Atlantic (Portuguese [...] Read more.
The ionospheric response at middle latitudes to geomagnetic storms is not yet very well understood. Total electron content (TEC) variations associated with eight strong geomagnetic storms between 2015 and 2022 obtained from GNSS receivers in the eastern area of the North Atlantic (Portuguese continental and insular territory) are studied in an attempt to fill this gap. It was found that for most of the studied geomagnetic storms, TEC variations are synchronous for the longitudinal ranges from 27° W and 9° W. In the southern part of the studied region (around 32° N), the amplitude of TEC variations is, in general, significantly higher than in the northern part (around 39° N). Some of the studied geomagnetic storms were associated with TEC variations that we interpret as effects of post-sunset equatorial plasma bubbles that travelled well north from their habitual region. Additionally, though most of the studied storms were accompanied by reports on different kinds of malfunction of GNSS systems (GPS; GALILEO and other), there is no clear pattern in their appearance in dependence on the geomagnetic/ionospheric storms’ strength, commencement time, and its characteristics, in general. Full article
(This article belongs to the Special Issue Ionospheric and Magnetic Signatures of Space Weather Events at Middle and Low Latitudes: Experimental Studies and Modelling (2nd Edition))
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19 pages, 4785 KiB  
Article
Inverse Modeling of Formaldehyde Emissions and Assessment of Associated Cumulative Ambient Air Exposures at Fine Scale
by Eduardo P. Olaguer
Atmosphere 2023, 14(6), 931; https://doi.org/10.3390/atmos14060931 - 26 May 2023
Cited by 2 | Viewed by 1801
Abstract
Among air toxics, formaldehyde (HCHO) is an important contributor to urban cancer risk. Emissions of HCHO in the United States are systematically under-reported and may enhance atmospheric ozone and particulate matter, intensifying their impacts on human health. During the 2021 Michigan-Ontario Ozone Source [...] Read more.
Among air toxics, formaldehyde (HCHO) is an important contributor to urban cancer risk. Emissions of HCHO in the United States are systematically under-reported and may enhance atmospheric ozone and particulate matter, intensifying their impacts on human health. During the 2021 Michigan-Ontario Ozone Source Experiment (MOOSE), mobile real-time (~1 s frequency) measurements of ozone, nitrogen oxides, and organic compounds were conducted in an industrialized area in metropolitan Detroit. The measured concentrations were used to infer ground-level and elevated emissions of HCHO, CO, and NO from multiple sources at a fine scale (400 m horizontal resolution) based on the 4D variational data assimilation technique and the MicroFACT air quality model. Cumulative exposure to HCHO from multiple sources of both primary (directly emitted) and secondary (atmospherically formed) HCHO was then simulated assuming emissions inferred from inverse modeling. Model-inferred HCHO emissions from larger industrial facilities were greater than 1 US ton per year while corresponding emission ratios of HCHO to CO in combustion sources were roughly 2 to 5%. Moreover, simulated ambient HCHO concentrations depended significantly on wind direction relative to the largest sources. The model helped to explain the observed HCHO concentration gradient between monitoring stations at Dearborn and River Rouge in 2021. Full article
(This article belongs to the Special Issue The Michigan-Ontario Ozone Source Experiment (MOOSE))
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15 pages, 2950 KiB  
Article
Application of Functional Principal Component Analysis in the Spatiotemporal Land-Use Regression Modeling of PM2.5
by Mahmood Taghavi, Ghader Ghanizadeh, Mohammad Ghasemi, Alessandro Fassò, Gerard Hoek, Kiavash Hushmandi and Mehdi Raei
Atmosphere 2023, 14(6), 926; https://doi.org/10.3390/atmos14060926 - 25 May 2023
Cited by 2 | Viewed by 1175
Abstract
Functional data are generally curves indexed over a time domain, and land-use regression (LUR) is a promising spatial technique for generating high-resolution spatial estimation of retrospective long-term air pollutants. We developed a methodology for the novel functional land-use regression (FLUR) model, which provides [...] Read more.
Functional data are generally curves indexed over a time domain, and land-use regression (LUR) is a promising spatial technique for generating high-resolution spatial estimation of retrospective long-term air pollutants. We developed a methodology for the novel functional land-use regression (FLUR) model, which provides high-resolution spatial and temporal estimations of retrospective pollutants. Long-term fine particulate matter (PM2.5) in the megacity of Tehran, Iran, was used as the practical example. The hourly measured PM2.5 concentrations were averaged for each hour and in each air monitoring station. Penalized smoothing was employed to construct the smooth PM2.5 diurnal curve using averaged hourly data in each of the 30 stations. Functional principal component analysis (FPCA) was used to extract FPCA scores from pollutant curves, and LUR models were fitted on FPCA scores. The mean of all PM2.5 diurnal curves had a maximum of 39.58 µg/m3 at 00:26 a.m. and a minimum of 29.27 µg/m3 at 3:57 p.m. The FPCA explained about 99.5% of variations in the observed diurnal curves across the city using just three components. The evaluation of spatially predicted long-term PM2.5 diurnal curves every 15 min provided a series of 96 high-resolution exposure maps. The presented methodology and results could benefit future environmental epidemiological studies. Full article
(This article belongs to the Special Issue Spatio-Temporal Analysis of Air Pollution)
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21 pages, 21022 KiB  
Article
Optimizing the Surrounding Building Configuration to Improve the Cooling Ability of Urban Parks on Surrounding Neighborhoods
by Qian Han, Xinge Nan, Han Wang, Yanjun Hu, Zhiyi Bao and Hai Yan
Atmosphere 2023, 14(6), 914; https://doi.org/10.3390/atmos14060914 - 24 May 2023
Cited by 5 | Viewed by 3640
Abstract
Urban parks reduce air temperatures within parks and surroundings by exerting the cooling island effect, significant for mitigating the urban microclimate. However, the park cooling effect may be influenced by the surrounding building configuration, and this needs to be studied in more detail, [...] Read more.
Urban parks reduce air temperatures within parks and surroundings by exerting the cooling island effect, significant for mitigating the urban microclimate. However, the park cooling effect may be influenced by the surrounding building configuration, and this needs to be studied in more detail, in particular, to explore how to maximize the cooling effect of parks by adjusting the surrounding building configuration. Thus, in this study, the effects of building height, building interval, and building orientation on the cooling effect of a small urban park were investigated using field measurements and ENVI-met numerical simulations. The results demonstrated that (1) building height, building interval, and building orientation all impact the park cooling effect, but their impacts vary. (2) Building height had the strongest effect on the park cooling intensity, and adjusting building height provided the maximum park cooling intensity (1.2 °C). (3) Building orientation had the most effect on the park cooling distance, 100 m downwind of the park. (4) The park cooling effect is best when the surrounding buildings were parallel to the prevailing wind direction, and the park cool island has the greatest intensity and range. This study can guide decision-makers in optimizing building configuration to maximize the park cooling effect. Full article
(This article belongs to the Section Biometeorology and Bioclimatology)
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20 pages, 7223 KiB  
Article
Airborne Air Pollutant Emission Characteristics of Mobile Vehicles in Taiwan
by Jiun-Horng Tsai, Jian-You Chen and Hung-Lung Chiang
Atmosphere 2023, 14(6), 916; https://doi.org/10.3390/atmos14060916 - 24 May 2023
Viewed by 1737
Abstract
This study examines the air pollutant emission characteristics, activity intensity, and trends of mobile sources from 2013 to 2021. The target pollutants include criteria pollutants (fine particulate matters, nitrogen oxides, and hydrocarbons) and hazardous air pollutants (benzene, formaldehyde, and BaP). The results indicated [...] Read more.
This study examines the air pollutant emission characteristics, activity intensity, and trends of mobile sources from 2013 to 2021. The target pollutants include criteria pollutants (fine particulate matters, nitrogen oxides, and hydrocarbons) and hazardous air pollutants (benzene, formaldehyde, and BaP). The results indicated that the activity intensity levels of road mobile sources in Taiwan were148 × 109, 156 × 109, 159 × 109, and 155 × 109 km/year in 2013, 2016, 2019, and 2021, respectively, with the largest proportion attributed to gasoline passenger cars (42.6%), followed by four-stroke motorcycles (32.6%). An emission factor of PM2.5 was estimated by EPA’s MOVES (Motor Vehicle Emission Simulator) model, and the results showed that the emission sequence was diesel > gasoline > motorcycle; the NOx emission factor was estimated using the MOBILE6.2 model, and the results showed that the order was diesel > gasoline > motorcycle; the HC emission factor was compiled with the use of gasoline vehicle dynamometer data, and the results showed that motorcycle > gasoline vehicles. Further results showed that the emission sequence for benzene was motorcycle > gasoline ≥ diesel; the formaldehyde emission sequence was diesel > motorcycle ≥ gasoline. The BaP emission factors of different vehicle types were estimated using MOVES, and the emission factors of old heavy-duty diesel vehicles were the highest. Full article
(This article belongs to the Special Issue Evaluation of Anthropogenic Emissions into the Atmosphere: Regional Scale Approach, Trends, and Large-Scale Mitigation)
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15 pages, 6598 KiB  
Article
Three-Dimensional Visualization of Long-Range Atmospheric Transport of Crop Pathogens and Insect Pests
by Marcel Meyer, William Thurston, Jacob W. Smith, Alan Schumacher, Sarah C. Millington, David P. Hodson, Keith Cressman and Christopher A. Gilligan
Atmosphere 2023, 14(6), 910; https://doi.org/10.3390/atmos14060910 - 23 May 2023
Cited by 1 | Viewed by 2510
Abstract
Some of the most devastating crop diseases and insect pests can be transmitted by wind over extremely long distances. These low-probability but high-impact events can have severe consequences for crop production and food security by causing epidemic outbreaks or devastating insect infestations in [...] Read more.
Some of the most devastating crop diseases and insect pests can be transmitted by wind over extremely long distances. These low-probability but high-impact events can have severe consequences for crop production and food security by causing epidemic outbreaks or devastating insect infestations in previously uninfected geographic areas. Two prominent examples that have recently caused substantial damage to agricultural production are novel strains of wheat rusts and desert locust swarm infestations. Whilst quantitative estimates of long-range atmospheric transport events can be obtained using meteorological transport simulations, the exact characteristics of three-dimensional spatiotemporal dynamics of crop pathogen transport and insect flight on extremely large spatial scales, over entire regions and continents, remain largely unknown. Here, we investigate the feasibility and usefulness of new advanced geospatial data visualization methods for studying extremely long-distance airborne transmission of crop pathogens and insect pests. We combine field surveillance data and a Lagrangian Particle Dispersion Model with novel techniques from computer graphics to obtain, for the first time, detailed three-dimensional visual insights into airborne crop pathogen and insect pest transport on regional and continental scales. Visual insights into long-distance dispersal of pests and pathogens are presented as a series of short 3D movies. We use interactive three-dimensional visual data analysis for explorative examination of long-range atmospheric transport events from a selection of outbreak and infestation sites in East Africa and South East Asia. The practical usefulness of advanced 3D visualization methods for improving risk estimates and early warning is discussed in the context of two operational crop disease and insect pest management systems (for wheat rusts and desert locusts). The tools and methods introduced here can be applied to other pathogens, pests, and geographical areas and can improve understanding of risks posed to agricultural production by crop disease and insect pest transmission caused by meteorological extreme events. Full article
(This article belongs to the Special Issue Agrometeorology, Agricultural Water Management and Impacts of Extreme Events)
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18 pages, 1327 KiB  
Article
Nexus between Social Vulnerability and Resilience to Agricultural Drought amongst South African Smallholder Livestock Households
by Yonas T. Bahta and Willem A. Lombard
Atmosphere 2023, 14(5), 900; https://doi.org/10.3390/atmos14050900 - 21 May 2023
Cited by 4 | Viewed by 1664
Abstract
Livestock farmers in Sub-Saharan Africa rely on rain-fed agriculture, which exposes them to the risks of agricultural drought. Agricultural drought has become a significant threat to the extreme mortality of livestock, thus negatively impacting social vulnerability and household resilience to agricultural drought and [...] Read more.
Livestock farmers in Sub-Saharan Africa rely on rain-fed agriculture, which exposes them to the risks of agricultural drought. Agricultural drought has become a significant threat to the extreme mortality of livestock, thus negatively impacting social vulnerability and household resilience to agricultural drought and extreme events. Researchers rarely empirically assess the connection between vulnerability and resilience, which are highly related concepts. By measuring and connecting vulnerability and resilience concepts closely related to disasters such as agricultural drought, this article makes a contribution to the body of disaster literature. The study aimed to empirically examine the relationship between smallholder livestock farming households’ social vulnerability and their resilience to agricultural drought. A survey of 217 smallholder livestock farmers was conducted. The Social Vulnerability Index (SVI), the Agricultural Drought Resilience Index (ADRI), and Pearson’s correlation coefficient were used for data analysis. A correlation was identified between resilience to agricultural drought and social vulnerability, indicating that smallholder livestock farmers are more susceptible to harm and lack the means to rebound effectively. Unsurprisingly, the majority of resource-poor smallholder livestock farmers (79%) lack safety nets during agricultural droughts. They are less resilient and more vulnerable households, leading them to social vulnerability. This study provides input/guidance to identify farming households with high social vulnerability and less resilience to threats and their capabilities of recouping and adopting after experiencing an agricultural drought. Additionally, looking at household resilience and social vulnerability to agricultural droughts could provide a way to pinpoint at-risk areas, assisting emergency planners in directing resources and intervention programs to those areas where assistance is most likely to be needed during disasters such as agricultural droughts. This implies that thorough policy intervention programs need to be tailored toward reducing damage or finding the path to recovery. Full article
(This article belongs to the Special Issue Agrometeorology, Agricultural Water Management and Impacts of Extreme Events)
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13 pages, 929 KiB  
Article
Investigation of Dynamical Complexity in Swarm-Derived Geomagnetic Activity Indices Using Information Theory
by Georgios Balasis, Adamantia Zoe Boutsi, Constantinos Papadimitriou, Stelios M. Potirakis, Vasilis Pitsis, Ioannis A. Daglis, Anastasios Anastasiadis and Omiros Giannakis
Atmosphere 2023, 14(5), 890; https://doi.org/10.3390/atmos14050890 - 19 May 2023
Cited by 1 | Viewed by 1863
Abstract
In 2023, the ESA’s Swarm constellation mission celebrates 10 years in orbit, offering one of the best ever surveys of the topside ionosphere. Among its achievements, it has been recently demonstrated that Swarm data can be used to derive space-based geomagnetic activity indices, [...] Read more.
In 2023, the ESA’s Swarm constellation mission celebrates 10 years in orbit, offering one of the best ever surveys of the topside ionosphere. Among its achievements, it has been recently demonstrated that Swarm data can be used to derive space-based geomagnetic activity indices, similar to the standard ground-based geomagnetic indices monitoring magnetic storm and magnetospheric substorm activity. Recently, many novel concepts originating in time series analysis based on information theory have been developed, partly motivated by specific research questions linked to various domains of geosciences, including space physics. Here, we apply information theory approaches (i.e., Hurst exponent and a variety of entropy measures) to analyze the Swarm-derived magnetic indices from 2015, a year that included three out of the four most intense magnetic storm events of the previous solar cycle, including the strongest storm of solar cycle 24. We show the applicability of information theory to study the dynamical complexity of the upper atmosphere, through highlighting the temporal transition from the quiet-time to the storm-time magnetosphere, which may prove significant for space weather studies. Our results suggest that the spaceborne indices have the capacity to capture the same dynamics and behaviors, with regards to their informational content, as traditionally used ground-based ones. Full article
(This article belongs to the Special Issue The Effect of Helio-Geomagnetic Activity in the Geo-Environment and by Extension to Human Health)
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16 pages, 2051 KiB  
Article
Future Ship Emission Scenarios with a Focus on Ammonia Fuel
by Daniel A. Schwarzkopf, Ronny Petrik, Josefine Hahn, Leonidas Ntziachristos, Volker Matthias and Markus Quante
Atmosphere 2023, 14(5), 879; https://doi.org/10.3390/atmos14050879 - 17 May 2023
Cited by 5 | Viewed by 3087
Abstract
Current efforts by the International Maritime Organization (IMO) to decarbonize the shipping sector have gained momentum, although the exact path to achieve this goal is currently unclear. However, it can be safely assumed that alternative cleaner and zero-carbon fuels will be key components [...] Read more.
Current efforts by the International Maritime Organization (IMO) to decarbonize the shipping sector have gained momentum, although the exact path to achieve this goal is currently unclear. However, it can be safely assumed that alternative cleaner and zero-carbon fuels will be key components in the strategy. In this work, three ship emission scenarios for 2025, 2040, and 2050 were developed that cover the area of the North and Baltic Seas. They aim at a fundamental transition in the usage of marine fuels towards ammonia as the mainly used fuel in 2050, via an intermediate step in 2040 with liquefied natural gas as the main fuel. Additionally, expected trends and developments for the shipping sector were implemented, i.e., a fleet growth by vessel size and number. Efficiency improvements were included that are in accordance with the Energy Efficiency Design Index of the IMO. The scenarios were created using a novel method based on modifications to a virtual shipping fleet. The vessels in this fleet were subject to decommission and renewal cycles that adapt them to the scenario’s target year. Emissions for this renewed shipping fleet were calculated with the Modular Ship Emission Modeling System (MoSES). With respect to ammonia engine technology, two cases were considered. The first case deals with compression ignition engines and marine gas oil as pilot fuel, while the second case treats spark ignition engines and hydrogen as the pilot fuel. The first case is considered more feasible until 2050. Reductions with the first case in 2050 compared to 2015 were 40% for CO2 emissions. However, CO2 equivalents were only reduced by 22%, with the difference mainly resulting from increased N2O emissions. NOX emissions were reduced by 39%, and different PM components and SO2 were between 73% and 84% for the same target year. The estimated NH3 slip from ammonia-fueled ships in the North and Baltic Seas was calculated to be 930 Gg in 2050. For the second ammonia engine technology that is considered more advanced, emission reductions were generally stronger and ammonia emissions smaller. Full article
(This article belongs to the Special Issue Atmospheric Shipping Emissions and Their Environmental Impacts)
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17 pages, 3948 KiB  
Article
Modeling of Organic Aerosol in Seoul Using CMAQ with AERO7
by Hyeon-Yeong Park, Sung-Chul Hong, Jae-Bum Lee and Seog-Yeon Cho
Atmosphere 2023, 14(5), 874; https://doi.org/10.3390/atmos14050874 - 16 May 2023
Cited by 3 | Viewed by 1820
Abstract
The Community Multiscale Air Quality (CMAQ) model with the 7th generation aerosol module (AERO7) was employed to simulate organic aerosol (OA) in Seoul, Korea, for the year 2016. The goal of the present study includes the 1-year simulation of OA using WRF-CMAQ with [...] Read more.
The Community Multiscale Air Quality (CMAQ) model with the 7th generation aerosol module (AERO7) was employed to simulate organic aerosol (OA) in Seoul, Korea, for the year 2016. The goal of the present study includes the 1-year simulation of OA using WRF-CMAQ with recently EPA-developed AERO7 with pcVOC (potential VOC from combustion) scale factor revision and analysis of the seasonal behavior of OA surrogate species in Seoul. The AERO7, the most recent version of the aerosol module of the CMAQ model, includes a new secondary organic aerosol (SOA) species, pcSOA (potential SOA from combustion), to resolve the inherent under-prediction problem of OA. The AERO7 classified OA into three groups: primary organic aerosol (POA), anthropogenic SOA (ASOA), and biogenic SOA (BSOA). Each OA group was further classified into 6~15 individual OA surrogate species according to volatility and oxygen content to model the aging of OA and the formation of SOA. The hourly emissions of POA and SOA precursors were compiled and fed into the CMAQ to successfully simulate seasonal variations of OA compositions and ambient organic-matter to organic-carbon ratios (OM/OC). The model simulation showed that the POA and ASOA were major organic groups in the cool months (from November to March) while BSOA was a major organic group in the warm months (from April to October) in Seoul. The simulated OM/OCs ranged from 1.5~2.1 in Seoul, which agreed well with AMS measurements in Seoul in May 2016. Full article
(This article belongs to the Special Issue Air Quality Prediction and Modeling)
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22 pages, 4036 KiB  
Article
Physicochemical Assessment of the Road Vehicle Traffic Pollution Impact on the Urban Environment
by Marcel Rusca, Tiberiu Rusu, Simona Elena Avram, Doina Prodan, Gertrud Alexandra Paltinean, Miuta Rafila Filip, Irina Ciotlaus, Petru Pascuta, Tudor Andrei Rusu and Ioan Petean
Atmosphere 2023, 14(5), 862; https://doi.org/10.3390/atmos14050862 - 11 May 2023
Cited by 8 | Viewed by 2274
Abstract
Vehicle traffic pollution requires complex physicochemical analysis besides emission level measuring. The current study is focused on two campaigns of emissions measurements held in May and September 2019 in Alba Iulia City, Romania. There was found a significant excess of PM2.5 for [...] Read more.
Vehicle traffic pollution requires complex physicochemical analysis besides emission level measuring. The current study is focused on two campaigns of emissions measurements held in May and September 2019 in Alba Iulia City, Romania. There was found a significant excess of PM2.5 for all measuring points and PM10 for the most circulated points during May, along with significant VOC and CO2 emissions. September measurements reveal threshold excess for all PM along with increased values for VOC and CO2 emissions. These are the consequences of the complex environmental interaction of the traffic. Street dust and air-suspended particle samples were collected and analyzed to evidence the PM2.5 and PM10 sources. Physicochemical investigation reveals highly mineralized particulate matter: PM2.5 fractions within air-suspended particle samples predominantly contain Muscovite, Kaolinite, and traces of Quartz and Calcite, while PM10 fractions within air-suspended particle samples predominantly contain Quartz and Calcite. These mineral fractions originate in street dust and are suspended in the atmosphere due to the vehicles’ circulation. A significant amount of soot was found as small micro-sized clusters in PM2.5 and fine micro-spots attached over PM10 particles, as observed by Mineralogical Optical Microscopy (MOM) and Fourier Transformed Infrared Spectroscopy (FTIR). GC-MS analysis found over 53 volatile compounds on the investigated floating particles that are related to the combustion gases, such as saturated alkanes, cycloalkanes, esters, and aromatic hydrocarbons. It proves a VOC contamination of the measured particulate matters that make them more hazardous for the health. Viable strategies for vehicle traffic-related pollutants mitigation would be reducing the street dust occurrence and usage of modern catalyst filters of the combustion gas exhausting system. Full article
(This article belongs to the Special Issue Road Emission: Recent Trends, Current Progress and Future Direction)
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29 pages, 9932 KiB  
Article
Projecting Bioclimatic Change over the South-Eastern European Agricultural and Natural Areas via Ultrahigh-Resolution Analysis of the de Martonne Index
by Ioannis Charalampopoulos, Fotoula Droulia and Ioannis X. Tsiros
Atmosphere 2023, 14(5), 858; https://doi.org/10.3390/atmos14050858 - 11 May 2023
Cited by 6 | Viewed by 2860
Abstract
The changing climate is closely related to changes in the bioclimate. This research deals with the present bioclimate and its projected evolution over the entirety of the natural and agricultural lands of south-eastern Europe and individual countries (Bulgaria, Greece, Kosovo, N. Macedonia, Romania, [...] Read more.
The changing climate is closely related to changes in the bioclimate. This research deals with the present bioclimate and its projected evolution over the entirety of the natural and agricultural lands of south-eastern Europe and individual countries (Bulgaria, Greece, Kosovo, N. Macedonia, Romania, and Serbia). For this purpose, an ultrahigh spatial resolution of the de Martonne bioclimatic index pattern was elaborated and analysed for the first time. The survey is performed over the reference period (1981–2010) and future time frames (2011–2040; 2041–2070; 2071–2100) under SSP370 and SSP585 emission scenarios. On a territorial level, both natural and agricultural areas appear as highly impacted by the future changes of bioclimate; the highest xerothermic trend is expected to influence the latter areas, mostly in 2071–2100 and under the higher emission scenario. The natural areas will face an expansion in the semidry class from 0.9% (of the total area) during the reference period to 5.6% during 2071–2100 under the RCP8.5 scenario as the dominant extremely humid class falls from 53.5% to 32.9% for the same periods and scenario. On the other hand, agricultural areas will face a more intense xerothermic alteration going from 4.9% to 17.7% for the semidry class and from 41.1% to 23.5% for the dominant very humid class for the same periods and scenario. This study presents the spatial statistics per country for the selected scenarios and periods to provide information for stakeholders. This study’s results highlight the necessity for intensifying adaptation plans and actions aiming at the feasibility of agricultural practices and the conservation of natural areas. Full article
(This article belongs to the Section Biometeorology and Bioclimatology)
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17 pages, 3329 KiB  
Article
Artificial Periodic Irregularities and Temperature of the Lower Thermosphere
by Nataliya V. Bakhmetieva, Gennadiy I. Grigoriev, Ilia N. Zhemyakov and Elena E. Kalinina
Atmosphere 2023, 14(5), 846; https://doi.org/10.3390/atmos14050846 - 9 May 2023
Cited by 1 | Viewed by 1417
Abstract
The results of temperature measurements in the lower thermosphere at altitudes of 90–130 km by the method of resonant scattering of radio waves on artificial periodic inhomogeneities (APIs) of the ionospheric plasma are presented. These inhomogeneities are created when the ionosphere is exposed [...] Read more.
The results of temperature measurements in the lower thermosphere at altitudes of 90–130 km by the method of resonant scattering of radio waves on artificial periodic inhomogeneities (APIs) of the ionospheric plasma are presented. These inhomogeneities are created when the ionosphere is exposed to powerful HF radio emission. The temperature profile was obtained from measurements of the relaxation time of the API scattered signal. The data processes and the method of the temperature determination are given in detail. The height and temporal resolutions of the API technique are of the order of 1 km and 15 s, respectively, making it possible to study both fast and slow processes in the lower thermosphere. Large temperature variability at altitudes of 90–130 km during the day and from day to day, due to the propagation of atmospheric waves, has been confirmed. The temporal variations of the atmospheric parameters take place with periods from 15 min to some hours. There are often height profiles of the temperature with the wave-like variations and with the vertical scale of about 4–10 km. The irregular temperature profiles were observed above 100 km. Full article
(This article belongs to the Special Issue Mesosphere and Lower Thermosphere)
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28 pages, 3072 KiB  
Article
HF-Induced Artificial Injection of Energetic Electrons from the Earth’s Radiation Belt as a Powerful Source for Modification of Ionized and Neutral Components of the Earth’s Atmosphere
by Vladimir L. Frolov and Arkady V. Troitsky
Atmosphere 2023, 14(5), 843; https://doi.org/10.3390/atmos14050843 - 9 May 2023
Cited by 2 | Viewed by 1722
Abstract
It has been found in experiments at the SURA mid-latitude heating facility that the modification of the ionospheric F2 layer by powerful HF radio waves gives rise to artificial injection of energetic electrons from the Earth’s radiation belt into the atmosphere. The [...] Read more.
It has been found in experiments at the SURA mid-latitude heating facility that the modification of the ionospheric F2 layer by powerful HF radio waves gives rise to artificial injection of energetic electrons from the Earth’s radiation belt into the atmosphere. The spectral, energy, and spatial characteristics of such an injection are presented in the paper. It is significant that the energetic electrons excite the atoms and molecules of the atmosphere to Rydberg energy levels, followed by the transition of the excited atoms and molecules to lower energy states, accompanied by the radiation of the microwave electromagnetic emissions. It has been shown that the artificial injection of energetic electrons can be considered as an independent powerful source of generation of secondary artificial turbulence, the effect of which manifests itself at ionospheric and mesospheric heights both near the heating facility and at a large distance from it up to a thousand or more kilometers. Examples of such generation are given. Full article
(This article belongs to the Special Issue Geomagnetic Storms and Their Influence on Atmosphere–Ionosphere Coupling)
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15 pages, 4530 KiB  
Review
Microplastic Pollution Research Based on the VOS Viewer Software: Research Trends, Ecological Effects, and Testing Methods
by Yange Wang, Bowen Zhang, Rongshuo Zhang, Yangbing Wei, Yunjing Wang and Rencheng Zhu
Atmosphere 2023, 14(5), 838; https://doi.org/10.3390/atmos14050838 - 8 May 2023
Cited by 2 | Viewed by 2143
Abstract
Microplastics (MPs) are receiving increasing attention because of their potential harm to the environment and human health. This research aims to summarize the abundance, toxicological effects, and analysis methods of MPs, as well as present their current status and trends in scientific research. [...] Read more.
Microplastics (MPs) are receiving increasing attention because of their potential harm to the environment and human health. This research aims to summarize the abundance, toxicological effects, and analysis methods of MPs, as well as present their current status and trends in scientific research. Bibliometric analysis confirmed a substantial rise in annual research papers on MPs, predominantly over the previous nine years. The central research areas relating to MPs include distribution, sources, toxic effects, analytical approaches, and adsorption of MPs with other pollutants. Airborne MPs are a primary source of microplastic pollution in remote areas. Humans may inhale and ingest MPs, leading to the accumulation of these particles in their bodies. Additionally, microplastics can have biological toxicity that poses a potential threat to human health. Standard procedures for sampling and both qualitative and quantitative analysis of microplastics in various environmental media must be established urgently to enable effective comparison of experimental conclusions. Full article
(This article belongs to the Special Issue Atmospheric Pollutants: Characteristics, Sources and Transport)
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15 pages, 6799 KiB  
Article
Energetic Particle Precipitation Influence on Tidal Variations of Thermosphere Parameters in September 2017
by Fedor S. Bessarab, Olga P. Borchevkina, Ivan V. Karpov, Vladimir V. Klimenko, Maxim V. Klimenko, Olesya S. Yakovchuk, Jan Maik Wissing and Eugene V. Rozanov
Atmosphere 2023, 14(5), 829; https://doi.org/10.3390/atmos14050829 - 5 May 2023
Viewed by 1231
Abstract
The role of energetic particle precipitation in the formation of thermospheric tides is investigated. Using the Global Self-consistent Model of the Thermosphere, Ionosphere, and Protonosphere (GSM TIP) and two models of energetic particle precipitation, APM (Auroral Precipitation Model) and AIMOS 2.0.-AISstorm (Atmospheric Ionization [...] Read more.
The role of energetic particle precipitation in the formation of thermospheric tides is investigated. Using the Global Self-consistent Model of the Thermosphere, Ionosphere, and Protonosphere (GSM TIP) and two models of energetic particle precipitation, APM (Auroral Precipitation Model) and AIMOS 2.0.-AISstorm (Atmospheric Ionization Module Osnabrück 2.0—Atmospheric Ionization during Substorms), we performed simulations for the period 3–12 September 2017. This period covers both geomagnetically quiet days and the storm of 7–8 September. The analysis shows that migrating tides diurnal wave (DW) and semidiurnal wave (SW) prevail on quiet days for both versions of the simulations. On the day of maximum storm development on 8 September and the day after—9 September, the nonmigrating components of tidal waves, mainly DW0 and SW0, are intensified. There are also increasing differences in the spatial structure of tides between the two versions of simulations, especially between diurnal and semidiurnal tides at 154 km. On the disturbance days, the amplitudes of diurnal and semidiurnal tides at 154 km in the APM version are markedly greater than the corresponding values in the AIMOS version. Thus, it should be noted that the integral characteristics of the ionization function from precipitations are more important for the formation of DW and SW than its spatial structure or the features of temporal variations. A comparison of the total electron content (TEC) maps for the two versions of the simulation showed that the AIMOS version nicely reproduces the experimental data for a quiet time. The APM version is less accurate for quiet time but simulates the quantitative increase to disturbed conditions at high and middle latitudes better. For model reproduction of observed TEC variations at low and equatorial latitudes, it is not enough to consider the thermospheric source of thermospheric tides. In this case, the role of atmosphere–ionosphere coupling is very important. Full article
(This article belongs to the Special Issue Geomagnetic Storms and Their Influence on Atmosphere–Ionosphere Coupling)
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30 pages, 10761 KiB  
Article
Evaluating the Role of Land Surface Moisture in Generating Asymmetrical Precipitation during the Landfall of Hurricane Florence (2018)
by Lindsey Rosenthal and Stephanie E. Zick
Atmosphere 2023, 14(5), 814; https://doi.org/10.3390/atmos14050814 - 30 Apr 2023
Viewed by 1190
Abstract
This study focuses on the role of land surface moisture in generating asymmetrical precipitation surrounding a nearly stationary Hurricane Florence (2018) during landfall. Previous idealized modeling studies have suggested that atmospheric stability varies surrounding a tropical cyclone (TC) during landfall, with the atmosphere [...] Read more.
This study focuses on the role of land surface moisture in generating asymmetrical precipitation surrounding a nearly stationary Hurricane Florence (2018) during landfall. Previous idealized modeling studies have suggested that atmospheric stability varies surrounding a tropical cyclone (TC) during landfall, with the atmosphere destabilizing off-shore and stabilizing on-shore. However, this finding has not been studied using a real modeling framework. Here, we produce high-resolution numerical simulations to examine the variations in precipitation and atmospheric stability surrounding Hurricane Florence. In addition to a control simulation (CTRL), two additional simulations are performed by altering the land surface cover to be moister (WETX) or drier (DRYX) compared with the CTRL. In the experiment, the altered land surface affects the equivalent potential temperature within the boundary layer. Due to changes in moisture, there are consistent but minor impacts on the spatial patterns of moist static instability. This study found that rainbands in the inner core and distant rainband regions responded differently to changes in land surface moisture. Within the inner core region of the TC, WETX produced more precipitation that was more symmetrical compared with DRYX. In DRYX, there was increased moist static instability in the outer rainband region over water and decreased moist static instability in the outer rainband region over land, which may have contributed to the enhanced precipitation asymmetries. Still, both experiments produced asymmetrical precipitation distributions, suggesting that alterations to land surface moisture had a minor impact on the precipitation asymmetries in Hurricane Florence. We conclude that precipitation asymmetries are primarily dynamically driven by weak to moderate vertical wind shear and asymmetries in moisture flux convergence. Full article
(This article belongs to the Section Meteorology)
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26 pages, 10597 KiB  
Article
NAO Seasonal Forecast Using a Multivariate Air–Sea Coupled Deep Learning Model Combined with Causal Discovery
by Bin Mu, Xin Jiang, Shijin Yuan, Yuehan Cui and Bo Qin
Atmosphere 2023, 14(5), 792; https://doi.org/10.3390/atmos14050792 - 26 Apr 2023
Cited by 4 | Viewed by 2165
Abstract
The North Atlantic Oscillation (NAO) is a major climatic phenomenon in the Northern Hemisphere, but the underlying air–sea interaction and physical mechanisms remain elusive. Despite successful short-term forecasts using physics-based numerical models, longer-term forecasts of NAO continue to pose a challenge. In this [...] Read more.
The North Atlantic Oscillation (NAO) is a major climatic phenomenon in the Northern Hemisphere, but the underlying air–sea interaction and physical mechanisms remain elusive. Despite successful short-term forecasts using physics-based numerical models, longer-term forecasts of NAO continue to pose a challenge. In this study, we employ advanced data-driven causal discovery techniques to explore the causality between multiple ocean–atmosphere processes and NAO. We identify the best NAO predictors based on this causality analysis and develop NAO-MCD, a multivariate air–sea coupled model that incorporates causal discovery to provide 1–6 month lead seasonal forecasts of NAO. Our results demonstrate that the selected predictors are strongly associated with NAO development, enabling accurate forecasts of NAO. NAO-MCD significantly outperforms conventional numerical models and provides reliable seasonal forecasts of NAO, particularly for winter events. Moreover, our model extends the range of accurate forecasts, surpassing state-of-the-art performance at 2- to 6-month lead-time NAO forecasts, substantially outperforming conventional numerical models. Full article
(This article belongs to the Special Issue Recent Advances in Air-Sea Interactions, Climate Variability, and Predictability)
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16 pages, 3428 KiB  
Article
Climate Indices and Their Impact on Maize Yield in Veracruz, Mexico
by Citlali Villa-Falfán, Ofelia Andrea Valdés-Rodríguez, Jorge Luis Vázquez-Aguirre and Fernando Salas-Martínez
Atmosphere 2023, 14(5), 778; https://doi.org/10.3390/atmos14050778 - 25 Apr 2023
Cited by 2 | Viewed by 1902
Abstract
The State of Veracruz (Mexico) is highly vulnerable to climate change. Therefore, it is necessary to identify and analyze local climate extreme trends and explore potential relationships between climate indices and maize. The objectives of this research were (1) to describe recent trends [...] Read more.
The State of Veracruz (Mexico) is highly vulnerable to climate change. Therefore, it is necessary to identify and analyze local climate extreme trends and explore potential relationships between climate indices and maize. The objectives of this research were (1) to describe recent trends of climate indices (1979–2018) and (2) to compare these climate indices with maize yields produced in Veracruz, Mexico, under rainfed conditions. The methodology calculated and analyzed the sector-specific climate indices (Rx5day, PRCPTOT, SPI6, R20mm, TXx, TNn, TXgt50p, and TXge35) in 18 observation sites using Climpact. Climate indices were calculated over the spring-summer agricultural cycle and correlated with rainfed maize yields. Results show increasing trends for Rx5day, TXx, TXgt50p, and TXge35 indices in 65%, 56%, 89%, and 67% of the analyzed sites, respectively, whereas decreasing trends in PRCPTOT and R20mm indices were detected in 59% and 47% of the sites. Significant correlations (p < 0.05) between climate indices and maize yield were found in eight municipalities, of which 62% were positive. In conclusion, extreme temperature and precipitation local events are increasing in frequency, duration, and intensity, and depending on the site’s local climate, these might positively or negatively impact maize yields. Full article
(This article belongs to the Special Issue Agrometeorology, Agricultural Water Management and Impacts of Extreme Events)
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30 pages, 3704 KiB  
Review
Deactivation Mechanism and Anti-Deactivation Measures of Metal Catalyst in the Dry Reforming of Methane: A Review
by Bo Yuan, Tao Zhu, Yiwei Han, Xueli Zhang, Meidan Wang and Chen Li
Atmosphere 2023, 14(5), 770; https://doi.org/10.3390/atmos14050770 - 23 Apr 2023
Cited by 12 | Viewed by 3456
Abstract
In recent decades, the massive emission of greenhouse gases, such as carbon dioxide and methane, into the atmosphere has had a serious impact on the ecological environment. The dry reforming of carbon dioxide and methane to syngas cannot only realize the resource utilization [...] Read more.
In recent decades, the massive emission of greenhouse gases, such as carbon dioxide and methane, into the atmosphere has had a serious impact on the ecological environment. The dry reforming of carbon dioxide and methane to syngas cannot only realize the resource utilization of methane and carbon dioxide but also reduce global climate change. It is of great significance in carbon emission reduction. Owing to the dry reforming of methane (DRM) being a strongly endothermic reaction, it needs to be carried out under high-temperature conditions. It makes the catalyst have problems of the sintering of metal, carbon deposition, and poisoning. This article revolves around the problem of catalyst deactivation during the DRM reaction. It expands upon the thermodynamics and mechanisms of the DRM reaction, analyzes the causes of metal catalyst deactivation due to carbon deposition, sintering, and poisoning, and summarizes how the active components, supports, and additives of metal catalysts restrain the DRM catalyst deactivation during the reaction. The analysis revealed that changing the type and size of the active metal, adjusting the properties of the support, and adding additives can further regulate the dispersion of the active component, the interaction between the active component and the support, the oxygen vacancies of the support, and the acidity and basicity of the catalyst surface, ultimately achieving control over the metal catalyst’s resistance to sintering, carbon deposition, and sulfur poisoning. In addition, it discusses the application of metal catalysts in photothermal and plasma-catalyzed DRM. Finally, it outlines the prospects for research on metal catalysts for the DRM. Full article
(This article belongs to the Special Issue Air Pollution Control in China: Progress, Challenges, and Perspectives (2nd Edition))
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20 pages, 2085 KiB  
Article
Comparisons of Spatial and Temporal Variations in PM2.5-Bound Trace Elements in Urban and Rural Areas of South Korea, and Associated Potential Health Risks
by Jayant Nirmalkar, Kwangyul Lee, Junyoung Ahn, Jiyi Lee and Mijung Song
Atmosphere 2023, 14(4), 753; https://doi.org/10.3390/atmos14040753 - 21 Apr 2023
Cited by 7 | Viewed by 2196
Abstract
PM2.5-bound trace elements were chosen for health risk assessment because they have been linked to an increased risk of respiratory and cardiovascular illness. Since the Korean national air quality standard for ambient particulate matter is based on PM2.5 mass concentration, [...] Read more.
PM2.5-bound trace elements were chosen for health risk assessment because they have been linked to an increased risk of respiratory and cardiovascular illness. Since the Korean national air quality standard for ambient particulate matter is based on PM2.5 mass concentration, there have only been a few measurements of PM2.5 particles together with trace elements that can be utilized to evaluate their effects on air quality and human health. Thus, this study describes the trace elements bound to PM2.5 in Seoul (urban area) and Seosan (rural area) using online nondestructive energy-dispersive X-ray fluorescence analysis from December 2020 to January 2021. At both the Seoul and Seosan sites, S, K, Si, Ca, and Fe constituted most of the PM2.5-bound trace elements (~95%); major components such as S, K, and soil (estimatedcalculatedcalculated based on oxides of Si, Fe, Ca, and Ti) were presumably from anthropogenic and crustal sources, as well as favorable meteorological conditions. During winter, synoptic meteorology favored the transport of particles from severely contaminated regions, such as the East Asian outflow and local emissions. The total dry deposition flux for crustal elements was 894.5 ± 320.8 µg m−2 d−1 in Seoul and 1088.8 ± 302.4 µg m−2 d−1 in Seosan. Moreover, potential health risks from the trace elements were estimated. Cancer risk values for carcinogenic trace elements (Cr, As, Ni, and Pb) were within the tolerable limit (1 × 10−6), suggesting that adults and children were not at risk of cancer throughout the study period in Seoul and Seosan. Furthermore, a potential risk assessment of human exposure to remaining carcinogens (Cr, As, Ni, and Pb) and non-carcinogens (Cu, Fe, Zn, V, Mn, and Se) indicated that these trace elements posed no health risks. Nevertheless, trace element monitoring, risk assessment, and mitigation must be strengthened throughout the study area to confirm that trace-element-related health effects remain harmless. Researchers and policymakers can use the database from this study on spatial and temporal variation to establish actions and plans in the future. Full article
(This article belongs to the Special Issue New Insights for Health and Environmental Impact Assessment of PM Released by Outdoor and Indoor Sources)
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14 pages, 3205 KiB  
Article
A Study of Elemental Composition and Risk Assessment Due to Exposure to Indoor PM10 in Two Residences in Mexico City
by Salvador Reynoso-Cruces, Javier Miranda-Martín-del-Campo and Juan Carlos Pineda-Santamaría
Atmosphere 2023, 14(4), 734; https://doi.org/10.3390/atmos14040734 - 19 Apr 2023
Cited by 2 | Viewed by 2005
Abstract
Samples of airborne particles with aerodynamic diameters smaller than 10 µm (PM10) were collected in 2021 at two households in the Metropolitan Area of Mexico City. Both sites are in areas with different characteristics (residential or industrial zones). Simultaneous sampling indoors [...] Read more.
Samples of airborne particles with aerodynamic diameters smaller than 10 µm (PM10) were collected in 2021 at two households in the Metropolitan Area of Mexico City. Both sites are in areas with different characteristics (residential or industrial zones). Simultaneous sampling indoors and outdoors was carried out at the two locations, using low-volume samplers. The study aimed to determine the indoor and outdoor gravimetric mass and elemental concentrations, identify emitting sources and possible penetration towards the households enhanced by natural ventilation, and assess risks to human health due to inhalation, ingestion, and dermal absorption, through hazard quotients. Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Se, and Pb concentrations were measured with X-ray fluorescence. Mass concentrations were higher indoors than outdoors, and most elemental concentrations had similar values in both environments. Cluster analysis was applied to identify possible emitting sources. The results showed a strong penetration of geogenic and industrial emissions at the Iztapalapa site, while only particles of industrial origin entered the interior of the Tlalnepantla dwelling, in both cases caused by the natural ventilation of the households. Health risks due to exposure to particles containing Fe, Ni, Cu, Zn, and Mn are not significant, and Pb and Cr only pose a risk via ingestion for men and women, although for children, there is a risk due to ingestion of all these elements. Full article
(This article belongs to the Special Issue Indoor Air Quality and Health Risk)
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14 pages, 3484 KiB  
Article
Study on the Hemispheric Asymmetry of Thermospheric Density Based on In-Situ Measurements from APOD Satellite
by Jiangzhao Ai, Yongping Li, Xianguo Zhang, Chao Xiao, Guangming Chen, Xiaoliang Zheng and Zhiliang Zhang
Atmosphere 2023, 14(4), 714; https://doi.org/10.3390/atmos14040714 - 14 Apr 2023
Cited by 1 | Viewed by 1568
Abstract
In this article, high spatiotemporal resolution data obtained by the atmospheric density detector carried by China’s APOD satellite are used to study the hemispheric asymmetry of thermospheric density. A detailed analysis is first performed on the dual magnetic storm event that occurred near [...] Read more.
In this article, high spatiotemporal resolution data obtained by the atmospheric density detector carried by China’s APOD satellite are used to study the hemispheric asymmetry of thermospheric density. A detailed analysis is first performed on the dual magnetic storm event that occurred near the autumnal equinox on 8 September 2017. The results show that the enhancement ratio of atmospheric density in the southern polar region (SPR) on the duskside was approximately 1.33–1.65 times that of the northern polar region (NPR), demonstrating a strong hemispheric asymmetry of thermospheric atmospheric density response during the magnetic storm. However, the asymmetry response was smaller on the dawnside, suggesting that the hemispheric density response asymmetry is related to local time (LT). The energy injection in high-latitude regions increases local atmospheric density and forms traveling atmospheric disturbances (TADs). TADs can propagate to low-latitude regions over several hours and affect the global distribution of thermospheric atmospheric density. Similarly, the geomagnetic index fitting slope of SPR relative density difference is greater than that of NPR. The SuperDARN convection pattern indicates that the plasma convection velocity of SPR is significantly greater than that of NPR, indicating that joule heating caused by neutral friction of ions in the Southern Hemisphere may be stronger. Subsequently, an analysis of annual solar activity and seasons was carried out on the thermospheric NPR, SPR atmospheric density, and their differences from December 2015 to December 2020. The results show that thermospheric atmospheric density decreases overall as the number of sunspots decreases. The differences between the NPR and SPR atmospheric densities in the thermosphere exhibits a noticeable annual periodicity. The NPR and SPR atmospheric densities appear to have different distribution characteristics in different seasons. The NPR density peak is mainly in March or April. In particular, the “double-peak” phenomenon occurred in 2017, with peaks in March and September, while the most obvious feature of SPR atmospheric density is that its minimum value occurs in the summer months of June and July. This paper reveals the annual, seasonal, and magnetic storm response characteristics of the hemispheric asymmetry of thermospheric atmospheric density, which has significant implications for the study of multilayer energy coupling of the magnetosphere–ionosphere–thermosphere. Full article
(This article belongs to the Section Upper Atmosphere)
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17 pages, 15655 KiB  
Article
A Statistical Analysis of Tropical Cyclone-Induced Low-Level Winds near Taiwan Island
by Lin Xue, Ying Li and Sen Yao
Atmosphere 2023, 14(4), 715; https://doi.org/10.3390/atmos14040715 - 14 Apr 2023
Cited by 1 | Viewed by 1666
Abstract
Using ERA5 reanalysis data and the tropical cyclone (TC) best track datasets from the China Meteorological Administration and Joint Typhoon Warning Center (from 1979 to 2021), TC-induced low-level winds near Taiwan Island are statistically analyzed. This study mainly concerns TC activity, low-level wind [...] Read more.
Using ERA5 reanalysis data and the tropical cyclone (TC) best track datasets from the China Meteorological Administration and Joint Typhoon Warning Center (from 1979 to 2021), TC-induced low-level winds near Taiwan Island are statistically analyzed. This study mainly concerns TC activity, low-level wind fields around Taiwan Island under TCs, and the detailed characteristics of TC wind structure. Results show that on average, 8.3 TCs enter the study region near Taiwan Island every year mainly from May to November, with more frequent and stronger TCs on the eastern and southern sides of Taiwan Island. For TC centers located at different positions around Taiwan Island, positive and negative vertical vorticity belts alternate between Taiwan Island and the TC center. Moreover, stronger and more frequent TC-induced winds mainly occur on the eastern side of Taiwan Island and the north of Taiwan Strait. TCs to the east of Taiwan Island have stronger maximum sustained wind than those on the western side of the island. Radii of the maximum wind (RMW) for TCs around Taiwan Island range from 5 to 90 nautical mile (nm, 9.3 to 116.7 km) with a mean value of 24.7 nm (44.4 km). Moreover, the RMWs of TCs are the largest (smallest) when the TC centers are located to the southwest (east) of the island. In addition, the outer sizes of TC winds vary from 52 to 360 nm (17.2 to 666.7 km) in the study region, with 187.4 nm (347.1 km) on average, and smaller values for TCs on the western side of the island. The average radii of severe winds, including R34, R50, and R64, are largest in the northeast quadrant and smallest in the southwest quadrant of the TC. The higher the specific wind speed is, the smaller the TC radius and the more symmetric its wind circle. These statistical results may provide references for TC gale forecasting and wind-resistant design for offshore engineering to mitigate TC-induced wind hazards. Full article
(This article belongs to the Special Issue Feature Papers in Meteorological Science)
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14 pages, 3728 KiB  
Article
On the Radon-Related Mechanism of the Seismo- and Volcanogenic Geomagnetic Anomalies: Experiments in Tlamacas Mountain (Volcano Popocatepetl Area) and Electrode Effect Model
by Vsevolod Yutsis, Anatolyi Kotsarenko, Vladimir Grimalsky and Sergey Pulinets
Atmosphere 2023, 14(4), 705; https://doi.org/10.3390/atmos14040705 - 12 Apr 2023
Cited by 1 | Viewed by 1556
Abstract
The noise-like behavior of the geomagnetic anomalies observed in Tlamacas station (volcano Popocatepetl, Mexico), linked to the ionization produced by intensive radon release, are presented in the experimental part of this study. The magnetic field perturbations produced by charge spreading currents within the [...] Read more.
The noise-like behavior of the geomagnetic anomalies observed in Tlamacas station (volcano Popocatepetl, Mexico), linked to the ionization produced by intensive radon release, are presented in the experimental part of this study. The magnetic field perturbations produced by charge spreading currents within the fair-weather electric field are considered in the theoretical model based on the electrode. The electric charges are generated by the air ionization due to radon emanation. The simulations demonstrated that the ionization of the air leads to magnetic field perturbations of about 0.001–0.1 nT in the ULF (ultra low frequency) range 10−3–10−1 Hz. Magnetic field perturbations can be higher when the radon emanation occurs in a region with terrain irregularities. Full article
(This article belongs to the Special Issue Feature Papers in Upper Atmosphere)
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13 pages, 21301 KiB  
Technical Note
On Saharan Air Layer Stability and Suppression of Convection over the Northern Tropical Atlantic: Case Study Analysis of a 2007 Dust Outflow Event
by Adrian Flores, Ricardo K. Sakai, Everette Joseph, Nicholas R. Nalli, Alexander Smirnov, Belay Demoz, Vernon R. Morris, Daniel Wolfe and Sen Chiao
Atmosphere 2023, 14(4), 707; https://doi.org/10.3390/atmos14040707 - 12 Apr 2023
Cited by 2 | Viewed by 1923
Abstract
A prominent Saharan Air Layer (SAL) was detected over the Northern Atlantic from the West African Coast to the Caribbean Sea in 2007. Data was collected from the Aerosols and Ocean Science Expedition (AEROSE), which encountered a major dust outflow on 13 and [...] Read more.
A prominent Saharan Air Layer (SAL) was detected over the Northern Atlantic from the West African Coast to the Caribbean Sea in 2007. Data was collected from the Aerosols and Ocean Science Expedition (AEROSE), which encountered a major dust outflow on 13 and 14 May 2007. These observational measurements came from onboard instrumentation and radiosondes that captured the dust-front event from 13 to 14 May 2007. Aerosol backscatter was confined within the Marine Boundary Layer (MBL), with layers detected up to 3 km. Aerosol Optical Depth (AOD) increased by one order of magnitude during the dust front, from 0.1 to 1. Downward solar radiation was also attenuated by 200 W/m2 and 100 W/m2 on the first and second days, respectively. A weaker gradient at and above 500 m from potential temperature profiles indicates a less-defined MBL, and an ambient air temperature of 26 °C on 14 May and 28 °C on 15 May were observed above 500 m, reinforcing the temperature inversion and static stability of the SAL. Subsequent days, clear and boundary-layer cloudy days were observed after the dust front. From 14 to 18 May, a Convective Inhibition (CIN) layer started to form at the top of the MBL, developing into a negative buoyancy from 17 to 23 May, and reinforcing the large-scale anticyclonic atmospheric conditions. These results show that the SAL acts as positive feedback on suppressing deep convection over the tropical Atlantic during this dust outflow and several days after its passage. Full article
(This article belongs to the Special Issue Aerosol–Light Interactions; Radiative Absorption and Emission by Particles of Atmosphere)
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18 pages, 2004 KiB  
Article
Analysis of Size Distribution, Chemical Composition, and Optical Properties of Mineral Dust Particles from Dry Deposition Measurement in Tenerife: Determined by Single-Particle Characterization
by Andebo Waza, Kilian Schneiders, Johannes Heuser and Konrad Kandler
Atmosphere 2023, 14(4), 700; https://doi.org/10.3390/atmos14040700 - 10 Apr 2023
Cited by 2 | Viewed by 2986
Abstract
In this paper, individual particle analysis by automated scanning electron microscopy (SEM) coupled with energy-dispersive X-ray (EDX) was used to assess the size-resolved information of composition, size distribution, complex refractive index, and mixing state of mineral dust aerosol particles collected using different passive [...] Read more.
In this paper, individual particle analysis by automated scanning electron microscopy (SEM) coupled with energy-dispersive X-ray (EDX) was used to assess the size-resolved information of composition, size distribution, complex refractive index, and mixing state of mineral dust aerosol particles collected using different passive and active samplers. In the study, over 120,000 particles from 53 samples were analyzed. Results show that dust particles are the dominating mineral particle type during this campaign, comprising different classes of silicates, Si-rich (quartz-like), Ca-rich (calcite-like), CaMg-rich (dolomite-like), and CaS-rich (gypsum-like). The results also show that there is no significant difference in composition between suspended and deposited dust particles. By using the particle composition, the size-resolved complex refractive index of dust particles was calculated. The real part of the refractive index varied between 1.71 and 1.53 for wavelengths in the range of 370 to 950 nm. The imaginary part of the refractive index, determined mostly by iron oxide, varied between 3.28×10−4 and 7.11×10−5 for wavelengths ranging from 250 nm to 1640 nm. In addition, the refractive index values showed a slight decrease with increasing particle size. We also analyzed the potential for buffering of the acid mobilization of iron by other dust compounds. For particles which contain both iron (Fe) and (unprocessed) calcium (Ca), acids that are able to dissolve insoluble Fe particles can react with the Ca particles before reacting with Fe, but eventually, with longer processing time, the Fe particles could be processed. By analyzing the ratio of sulfate mass to the total aerosol mass of individual particles, the mixing state of sulfate particles to the total dust particles was investigated. The analysis showed that the finer dust particles were associated with higher content of sulfate, while the coarse dust particles correspond to lower sulfate contents, revealing that only fine mode sulfate is more internally mixed with mineral dust aerosol particles. Full article
(This article belongs to the Special Issue Chemical Composition and Sources of Particles in the Atmosphere)
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11 pages, 3223 KiB  
Article
Assessment of Mobile Air Cleaners to Reduce the Concentration of Infectious Aerosol Particles Indoors
by Christian J. Kähler, Rainer Hain and Thomas Fuchs
Atmosphere 2023, 14(4), 698; https://doi.org/10.3390/atmos14040698 - 8 Apr 2023
Cited by 3 | Viewed by 1860
Abstract
Airborne transmission via aerosol particles without close human contact is a possible source of infection with airborne viruses such as SARS-CoV-2 or influenza. Reducing this indirect infection risk, which is mostly present indoors, requires wearing adequate respiratory masks, the inactivation of the viruses [...] Read more.
Airborne transmission via aerosol particles without close human contact is a possible source of infection with airborne viruses such as SARS-CoV-2 or influenza. Reducing this indirect infection risk, which is mostly present indoors, requires wearing adequate respiratory masks, the inactivation of the viruses with radiation or electric charges, filtering of the room air, or supplying ambient air by means of ventilation systems or open windows. For rooms without heating, ventilation, and air conditioning (HVAC) systems, mobile air cleaners are a possibility for filtering out aerosol particles and therefore lowering the probability of indirect infections. The main questions are as follows: (1) How effectively do mobile air cleaners filter the air in a room? (2) What are the parameters that influence this efficiency? (3) Are there room situations that completely prevent the air cleaner from filtering the air? (4) Does the air cleaner flow make the stay in the room uncomfortable? To answer these questions, particle imaging methods were employed. Particle image velocimetry (PIV) was used to determine the flow field in the proximity of the air cleaner inlet and outlet to assess regions of unpleasant air movements. The filtering efficiency was quantified by means of particle image counting as a measure for the particle concentration at multiple locations in the room simultaneously. Moreover, different room occupancies and room geometries were investigated. Our results confirm that mobile air cleaners are suitable devices for reducing the viral load indoors. Elongated room geometries, e.g., hallways, lead to a reduced filtering efficiency, which needs to be compensated by increasing the volume flow rate of the device or by deploying multiple smaller devices. As compared to an empty room, a room occupied with desks, desk separation walls, and people does not change the filtering efficiency significantly, i.e., the change was less than 10%. Finally, the flow induced by the investigated mobile air cleaner does not reach uncomfortable levels, as by defined room comfort standards under these conditions, while at the same time reaching air exchange rates above 6, a value which is recommended for potentially infectious environments. Full article
(This article belongs to the Special Issue Research on Indoor Air Cleaners for Particulate, Microbiological and Gaseous Pollutants)
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18 pages, 3649 KiB  
Article
Frost Risk Assessment in Slovenia in the Period of 1981–2020
by Zala Žnidaršič, Gregor Gregorič, Andreja Sušnik and Tjaša Pogačar
Atmosphere 2023, 14(4), 683; https://doi.org/10.3390/atmos14040683 - 5 Apr 2023
Cited by 2 | Viewed by 1243
Abstract
As spring frost proves to be an increasing risk throughout Slovenia and Europe, a better assessment of frost risk is needed. The statistical approach presented in this article consists of the conditional probability that the last spring frost occurs before budburst or flowering. [...] Read more.
As spring frost proves to be an increasing risk throughout Slovenia and Europe, a better assessment of frost risk is needed. The statistical approach presented in this article consists of the conditional probability that the last spring frost occurs before budburst or flowering. The analysis was conducted using two separate phenological models and phenological data of various grapevine (Vitis vinifera L.), apple (Malus domestica), and sweet cherry (Prunus avium L.) varieties in locations across Slovenia. The increase in risk of spring frost for grapevine ranged from 1 to 1980, from 0.06 to 12 for apple, and from 1 to 180 for sweet cherry. Overall, the varieties most prone to frost proved to be Refošk (Teran) and Merlot grapevine varieties as well as the Germersdorf sweet cherry variety. We have identified the location in the hilly region with moderate climate where the Bobovec apple variety is grown as the least exposed to frost. Although counterintuitive, the GDD generally proved somewhat more efficient than the two-phase phenological model BRIN, although not in all cases. For the purpose of the study, the phenological models were calibrated, and the model parameters can serve as invaluable information for further research of this topic. Full article
(This article belongs to the Special Issue Vegetation and Climate Relationships (2nd Edition))
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19 pages, 7929 KiB  
Article
Impacts of Urban Development between 2002 and 2022 on the Effects of Sea Breezes in Sendai, Japan—Analyzing Heat Balance Mechanism in Urban Space
by Yonghang Xie, Yasuyuki Ishida, Hironori Watanabe and Akashi Mochida
Atmosphere 2023, 14(4), 677; https://doi.org/10.3390/atmos14040677 - 3 Apr 2023
Cited by 5 | Viewed by 1898
Abstract
Sea breezes are important in a coastal urban climate; however, the impact of urban development on the effects of sea breezes, which decrease air temperature and increase humidity, has not been understood quantitatively. To quantitatively evaluate this impact in Sendai, Japan over the [...] Read more.
Sea breezes are important in a coastal urban climate; however, the impact of urban development on the effects of sea breezes, which decrease air temperature and increase humidity, has not been understood quantitatively. To quantitatively evaluate this impact in Sendai, Japan over the past twenty years, this study analyzed the heat balance mechanisms in urban spaces based on the simulation results of the Weather Research and Forecasting (WRF) model coupled with Local Climate Zone (LCZ) maps. Compared to the observation data on air temperature, specific humidity, and wind in August 2002, results of the numerical simulation, using the 2002 LCZ map and the meteorological conditions of August 2002, confirmed that the WRF model could reproduce meteorological factors well. Thereafter, two numerical simulations using the LCZ maps from 2002 and 2022 were conducted based on the same meteorological condition, from 25 July to 1 September 2008, to extract the impact of urban development on the effects of sea breeze. Consequently, when land use changed from urban built-up land to natural land cover, both the effects of sea breeze—decreasing air temperature and increasing humidity—decreased. Additionally, increases in LCZ 3 (compact low rise), mainly from LCZ 6 (open low rise) and LCZ 9 (sparsely built), decreased the effects of sea breeze (decreasing air temperature and increasing humidity) by 5% and 10%, respectively, in areas around Sendai Station. This was because the consumption of the sea breeze’s potential to decrease air temperature and increase humidity increased and the wind speed of sea breezes decreased in the windward areas of Sendai Station. These results provide new insights into the impact of urban development on the effects of sea breeze and quantitatively reveal changes in the effects of sea breeze. Full article
(This article belongs to the Special Issue Strategies for Mitigation and Adaptation to Urban Heat)
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19 pages, 12702 KiB  
Article
Trends and Features of Thunderstorms and Lightning Activity in the Upper Volga Region
by Svetlana Dementyeva, Maria Shatalina, Alena Popykina, Fedor Sarafanov, Mikhail Kulikov and Evgeny Mareev
Atmosphere 2023, 14(4), 674; https://doi.org/10.3390/atmos14040674 - 2 Apr 2023
Cited by 4 | Viewed by 2036
Abstract
An increase in the frequency of atmospheric hazards in a changing climate has attracted interest in the study of regional features of mesoscale convective systems and trends of lightning activity. Severe convective storms are the most destructive weather events causing substantial damage and [...] Read more.
An increase in the frequency of atmospheric hazards in a changing climate has attracted interest in the study of regional features of mesoscale convective systems and trends of lightning activity. Severe convective storms are the most destructive weather events causing substantial damage and fatalities. In this paper, we analyze general trends in the lightning activity in the Upper Volga region and identify the particular features of a severe thunderstorm on 13–14 July 2020. The analysis of the annual variability of the lightning activity in the Upper Volga region, carried out according to the World-Wide Lightning Location Network (WWLLN) data, has shown that the total number of discharges during the convective seasons of 2016–2021 increased. For the convective season of 2020, the daily number of discharges in the neighborhood of Nizhny Novgorod (the center of the region) is calculated according to the WWLLN data and the electric field mill (EFM) measurements. It is revealed that the most powerful (per convective season) thunderstorms have a number of similarities both according to observations and numerical simulation. The thunderstorm on 13–14 July was numerically simulated using the Weather Research and Forecasting (WRF) model in combination with calculations of the electric parameters (such as electric potential and intracloud electric field). The simulations were carried out using two parametrizations of microphysical processes to reveal the features associated with allowance for aerosol particles. The data from the meteorological radar and WWLLN were used to validate the radar reflectivity simulation results of the WRF model. Some features of the thunderstorm evolution characteristic for each of the microphysical parametrizations were identified. In general, the non-aerosol parametrization gives a more correct description of the development of severe thunderstorms in the Upper Volga region (with the exception of the final stage of the convective system development). For a convective event to have the required duration (more than 6 h), aerosol particles should be taken into account. Full article
(This article belongs to the Special Issue Future Trends of Our Atmospheric Electric Environments)
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19 pages, 10168 KiB  
Article
Decomposing Fast and Slow Responses of Global Cloud Cover to Quadrupled CO2 Forcing in CMIP6 Models
by Xixun Zhou, Hua Zhang, Qiuyan Wang and Bing Xie
Atmosphere 2023, 14(4), 653; https://doi.org/10.3390/atmos14040653 - 30 Mar 2023
Cited by 1 | Viewed by 1821
Abstract
Cloud changes and their attribution under global warming still remains a challenge in climatic change studies, especially in decomposing the fast and slow cloud responses to anthropogenic forcing. In this study, the responses of global cloud cover to the quadrupled CO2 forcing [...] Read more.
Cloud changes and their attribution under global warming still remains a challenge in climatic change studies, especially in decomposing the fast and slow cloud responses to anthropogenic forcing. In this study, the responses of global cloud cover to the quadrupled CO2 forcing are investigated quantitatively by decomposing the total response into fast and slow ones using the multi-model data from the Coupled Model Intercomparison Project Phase 6 (CMIP6). During the quasi-equilibrium period after the quadrupling of CO2 forcing, the global mean changes of simulated total cloud cover (TCC) in the total, fast, and slow responses are −2.42%, −0.64%, and −1.78%, respectively. Overall, the slow response dominates the total response in most regions over the globe with similar spatial patterns. TCC decreases at middle and low latitudes but increases at high latitudes in the total and slow responses. Whereas, it mainly decreases in the middle and low latitudes of the southern hemisphere as well as in the middle and high latitudes of the northern hemisphere in the fast response. A change in vertical motion is the major contributor to the cloud cover change at middle and low latitudes, while the decrease in upper atmospheric temperature leads to an increase in high cloud cover at high latitudes. In addition, the anomaly in water vapor convergence/diffusion also contributes to the cloud cover increase/decrease at low latitudes. Full article
(This article belongs to the Special Issue Climate Change and Climate Variability, and Their Impact on Extreme Events)
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25 pages, 7705 KiB  
Article
Diurnal Outdoor Thermal Comfort Mapping through Envi-Met Simulations, Remotely Sensed and In Situ Measurements
by Edoardo Fiorillo, Lorenzo Brilli, Federico Carotenuto, Letizia Cremonini, Beniamino Gioli, Tommaso Giordano and Marianna Nardino
Atmosphere 2023, 14(4), 641; https://doi.org/10.3390/atmos14040641 - 29 Mar 2023
Cited by 9 | Viewed by 3277
Abstract
Physiological equivalent temperature (PET) is one of most used indices for outdoor human well-being evaluation; its determination is particularly helpful for adaptation strategies in built-up areas affected by the urban heat island (UHI) phenomenon. In this work, we presented a methodology to compute [...] Read more.
Physiological equivalent temperature (PET) is one of most used indices for outdoor human well-being evaluation; its determination is particularly helpful for adaptation strategies in built-up areas affected by the urban heat island (UHI) phenomenon. In this work, we presented a methodology to compute spatially and temporally resolved PET values during a heatwave at the city level, based on a combination of satellite products, in situ measurements and Envi-met model runs upscaled from specific test areas to the broader city. The method exploits the ECOSTRESS sensor to detect surface thermal patterns at different diurnal times by developing an hourly based index called hUHTI (hourly urban heatwave thermal index) that serves as a proxy. A case study on Prato (Italy) municipality during the 2021 summer heatwave events is presented. Based on the available satellite products, a set of six hourly diurnal PET maps at 10 m spatial resolution were derived and daytime outdoor thermal patterns and trends were investigated according to land cover. hUHTI index resulted a more suitable tool as PET proxy compared to the sole ECOSTRESS land surface temperature (LST) product, especially for morning and evening times. Hourly PET maps were summarized by the use of an average exceedance map providing public administrations and stakeholders a synthetic tool for urban regeneration purposes at city scale. Full article
(This article belongs to the Special Issue Feature Papers in Biometeorology)
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20 pages, 8927 KiB  
Article
Urban Heat Mitigation towards Climate Change Adaptation: An Eco-Sustainable Design Strategy to Improve Environmental Performance under Rapid Urbanization
by Mehdi Makvandi, Wenjing Li, Xiongquan Ou, Hua Chai, Zeinab Khodabakhshi, Jiayan Fu, Philip F. Yuan and Elyse de la Joie Horimbere
Atmosphere 2023, 14(4), 638; https://doi.org/10.3390/atmos14040638 - 28 Mar 2023
Cited by 13 | Viewed by 4035
Abstract
Rapid urbanization has led to drastic land-use/cover changes (LUCCs) and urban heat islands (UHIs), negatively altering the urban climate and air quality. LUCC’s significant impacts on human health and energy consumption have inspired researchers to develop nature-based solutions to mitigate UHIs and improve [...] Read more.
Rapid urbanization has led to drastic land-use/cover changes (LUCCs) and urban heat islands (UHIs), negatively altering the urban climate and air quality. LUCC’s significant impacts on human health and energy consumption have inspired researchers to develop nature-based solutions to mitigate UHIs and improve air quality. However, integrating GIS-CFD modeling for urban heat mitigation towards climate change adaptation was largely neglected for eco-sustainable urban design in rapidly urbanizing areas. In this study, (1) long-term LUCC and meteorological analysis were conducted in the Wuhan metropolitan area from 1980 to 2016; (2) to mitigate the adverse effects of LUCC under a speedy development process, the role and relevance of optimizing building morphology and urban block configuration were discussed; (3) and particular design attention in strategy towards climate change adaptation for environmental performance improvement was paid in Wuhan’s fast-growing zones. The results show that UHII in 1980 was less severe than in 2016. Air temperature (Ta) increased by 0.4 °C on average per decade in developing areas. This increases the severity of UHII in urban fringes. It is found obligatory for a nature-based design to adopt urban morphology indicators (UMIs) such as average building height (μBH), sky view factors (ψSVF), and building density (BD/λp = % of built area) towards these changes. Further, on-site measurement revealed that λp is the most effective indicator for increasing urban heat around the buildings and boosting UHII. Using UMIs and a combined three-in-one regulation strategy based on μBH of common building types of high-rise (BHA), mid-rise (BHB), and low-rise (BHC) buildings can effectively contribute to regulating Ta and air movement within block configuration. As a result of this study’s strategy, urban heat is mitigated via reinforcing wind in order to adapt to climate change, which impacts the quality of life directly in developing areas. Full article
(This article belongs to the Special Issue Strategies for Mitigation and Adaptation to Urban Heat)
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11 pages, 2213 KiB  
Article
TEC and ROTI Measurements from a New GPS Receiver at BOWEN University, Nigeria
by Olawale S. Bolaji, Rafiat O. Kaka, Wayne A. Scales, Joshua B. Fashae, Yuxiang Peng, A. Babatunde Rabiu, Joshua O. Fadiji and Aanuoluwapo Ojelade
Atmosphere 2023, 14(4), 636; https://doi.org/10.3390/atmos14040636 - 28 Mar 2023
Cited by 3 | Viewed by 2276
Abstract
Scintillation and total electron content (TEC) are the two major examples of the top-side ionospheric parameters that are recorded differently by most Global Positioning System (GPS) receivers. The new GPS sensor created by the Atmospheric and Space Technology Research Associates (ASTRA), Cornell University, [...] Read more.
Scintillation and total electron content (TEC) are the two major examples of the top-side ionospheric parameters that are recorded differently by most Global Positioning System (GPS) receivers. The new GPS sensor created by the Atmospheric and Space Technology Research Associates (ASTRA), Cornell University, and the University of Texas, Austin have capability to record scintillation and TEC fluctuations simultaneously. Hence, the Connected Autonomous Space Environment Sensor (CASES) from ASTRA is a software-defined GPS receiver with the dual frequency of L1 C/A and L2C codes for space-weather monitoring and can be remotely programmed via an internet source. The receiver employs numerous novel techniques that make it suitable for space-weather studies compared to other nearby GPS receivers, such as different methods for eliminating local clock effects, an advanced triggering mechanism for determining scintillation onset, data buffering to permit observation of the prelude to scintillation, and data-bit prediction and wipe-off for robust tracking. Moreover, the CASES hardware is made up of a custom-built dual frequency, a digital signal processor board, and a “single board computer” with an ARM microcontroller. We have used the CASES GPS receiver newly installed at Bowen University, Iwo, Nigeria, to investigate the TEC and the rate of the TEC index (ROTI) around the equatorial region. Measurements of the TEC and ROTI showed similar variation trends in monthly, seasonal, and annual periods when compared to TEC and ROTI measurements from a nearby station, BJCO at Cotonou, Benin Republic. The newly installed GPS receiver looks promising for scientific use as it is the only one operational in Nigeria at the moment. Full article
(This article belongs to the Special Issue Ionospheric and Magnetic Signatures of Space Weather Events at Middle and Low Latitudes: Experimental Studies and Modelling (2nd Edition))
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12 pages, 6027 KiB  
Article
Teleconnection between the Surface Wind of Western Patagonia and the SAM, ENSO, and PDO Modes of Variability
by Carolina Gómez-Fontealba, Valentina Flores-Aqueveque and Stephane Christophe Alfaro
Atmosphere 2023, 14(4), 608; https://doi.org/10.3390/atmos14040608 - 23 Mar 2023
Cited by 1 | Viewed by 1717
Abstract
The Southern Westerly Wind (SWW) belt is one of the most important atmospheric features of the Southern Hemisphere (SH). In Patagonia, these winds control the precipitation rates at the windward side of the southern Andes, and rainfall is very sensitive to any change [...] Read more.
The Southern Westerly Wind (SWW) belt is one of the most important atmospheric features of the Southern Hemisphere (SH). In Patagonia, these winds control the precipitation rates at the windward side of the southern Andes, and rainfall is very sensitive to any change (strength and/or latitudinal position) in the wind belt. The present-day behavior of the SWW, also known as westerlies, is characterized by remarkable seasonality. This wind belt also varies at interannual-to-decadal time scales, associated with the influence of atmospheric phenomena such as the El Niño–Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), respectively. Moreover, during the past few decades, the westerlies have shown an increase in their core strength influenced by changes in the Southern Annular Mode (SAM). However, what controls the long-term variability of the SWW at the high latitudes of the SH is still a matter of debate. This work statistically analyzes the influence of large-scale modes of variability, such as ENSO and PDO on the SAM and the frequency of the strong SWW from ERA5 reanalysis data of southwestern Patagonia (~51°S), where the current core of this belt is located. Our results confirm the relation between strong wind anomalies and the SAM. In addition, the temporal variations of strong winds are also significantly affected by the PDO, but there is no detectable influence of the ENSO on their frequency. This shows that future studies focused on reconstructing wind history from aeolian particles of lake sediments from southwestern Patagonia could also provide information about the modes of variability that influence strong wind frequency. Full article
(This article belongs to the Special Issue Paleoclimate Reconstruction)
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26 pages, 19193 KiB  
Article
Evaluating CMIP6 Historical Mean Precipitation over Africa and the Arabian Peninsula against Satellite-Based Observation
by Isaac Kwesi Nooni, Faustin Katchele Ogou, Abdoul Aziz Saidou Chaibou, Francis Mawuli Nakoty, Gnim Tchalim Gnitou and Jiao Lu
Atmosphere 2023, 14(3), 607; https://doi.org/10.3390/atmos14030607 - 22 Mar 2023
Cited by 9 | Viewed by 3405
Abstract
This study evaluated the historical precipitation simulations of 49 global climate models (GCMs) of the Coupled Model Intercomparison Project Phase 6 (CMIP6) in reproducing annual and seasonal precipitation climatology, linear trends, and their spatial correlation with global SST across Africa and the Arabian [...] Read more.
This study evaluated the historical precipitation simulations of 49 global climate models (GCMs) of the Coupled Model Intercomparison Project Phase 6 (CMIP6) in reproducing annual and seasonal precipitation climatology, linear trends, and their spatial correlation with global SST across Africa and the Arabian Peninsula during the period of 1980–2014, using Global Precipitation Climatology Centre (GPCP) data as a reference. Taylor’s diagram was used to quantify the strengths and weaknesses of the models in simulating precipitation. The CMIP6 multi-mean ensemble (MME) and the majority of the GCMs replicated the dominant features of the spatial and temporal variations reasonably well. The CMIP6 MME outperformed the majority of the individual models. The spatial variation of the CMIP6 MME closely matched the observation. The results showed that at annual and seasonal scales, the GPCP and CMIP6 MME reproduced a coherent spatial pattern in terms of the magnitude of precipitation. The humid region received >300 mm and the arid region received <50 mm across Africa and the Arabian Peninsula. The models from the same modeling centers replicated the precipitation levels across different seasons and regions. The CMIP6 MME and the majority of the individual models overestimate (underestimate) in humid (arid and semi-arid)-climate zones. The annual and pre-monsoon seasons (i.e., DJFMA) were better replicated in the CMIP6 GCMs than in the monsoon-precipitation model (MJJASON). The CMIP6 MME (GPCP) showed stronger wetting (drying) trends in the northern hemisphere. In contrast, a strong drying trend in the CMIP6 MME and a weak wetting trend in the GPCP were shown in the Southern Hemisphere. The CMIP6 MME captures the spatial pattern of linear trends better than individual models across different climate zones and regions. The relationship between precipitation and sea-surface temperature (SST) exhibited a high spatial correlation (−0.80 and 0.80) with large variability across different regions and climate zones. The GPCP (CMIP6 MME) exhibited a heterogenous (homogeneous) spatial pattern, with higher correlation coefficients recorded in the CMIP6 MME than in the GPCP in all cases. Individual models from the same modeling centers showed spatial homogeneity in correlation values. The differences exhibited by the individual GCMs highlight the significance of each model’s unique dynamics and physics; however, model selection should be considered for specific applications. Full article
(This article belongs to the Special Issue Precipitation in Africa)
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18 pages, 5519 KiB  
Article
Simulation and Analysis of the Influence of Sounding Rocket Outgassing on In-Situ Atmospheric Detection
by Zhiliang Zhang, Yueqiang Sun, Yongping Li, Jiangzhao Ai, Xiaoliang Zheng and Wei Wang
Atmosphere 2023, 14(3), 603; https://doi.org/10.3390/atmos14030603 - 22 Mar 2023
Viewed by 1561
Abstract
The Meridian Project’s sounding rocket mission uses a mass spectrometer to conduct in-situ atmospheric detection. In order to assess the influence of surface material outgassing and the attitude control jet on the spectrometer’s detection, a sounding rocket platform was modeled and simulated. Using [...] Read more.
The Meridian Project’s sounding rocket mission uses a mass spectrometer to conduct in-situ atmospheric detection. In order to assess the influence of surface material outgassing and the attitude control jet on the spectrometer’s detection, a sounding rocket platform was modeled and simulated. Using the physical field simulation software COMSOL and the Monte Carlo method, this study investigated whether the gas molecules from the two cases could enter the in-situ atmospheric mass spectrometer’s sensor sampling port after colliding with the background atmosphere. The simulation results show that the influence of surface material outgassing on the in-situ atmospheric detection is very small, even under the conditions of medium solar activity and medium geomagnetic activity, while the influence of the attitude control jet on the in-situ atmospheric detection is large but can be reduced by reducing the low-altitude attitude control operation and decreasing the transmission probability. Through simulation optimization and according to engineering needs, increasing the nozzle outlet cross-sectional area, increasing the temperature of the gas used for attitude control, increasing the nozzle rotation angle, increasing the nozzle outlet angle, or increasing the nozzle center height can reduce the transmission probability. This model can simulate and analyze the influence of both surface material outgassing and attitude control jets on in-situ atmospheric detection, optimize relevant parameters, and provide new ideas for relevant work. Full article
(This article belongs to the Section Upper Atmosphere)
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