Improvement of Heavy Rainfall Simulated with SST Adjustment Associated with Mesoscale Convective Complexes Related to Severe Flash Flood in Luwu, Sulawesi, Indonesia
Round 1
Reviewer 1 Report
Yulihastin et al. submitted teh article entitled Characteristics of Mesoscale Convective Complexes that Triggered Heavy Rainfall to MDPI atmosphere. The paper investigates the driver of the flash flood that hit Luwu, Sulawesi in Indonesia, on 13 July 2020. It incluses observation analysis from global reanalysis/observation and WRF simulation. The WRF model clearly improves the location of rainfall as it runs on a 1km resolution while observation remains limited due to the low nb of obs stations and the coarse resolution of satellite (GSmap at 0.1deg). The WRF model reached a 1km resolution on d03.
The main aspect of the paper is a WRF experiment testing the role of SST to improve rainfall location and intensity. That aspect is not valorised enough as it is unclear from the title and abstract that actually the main contribution of that paper. I think that is also its main novelty as well as the description of a MCC in a complex area. The paper provide convincing Figures and quality interpretation sometimes a bit too fast.
General comments
Try to get Figure just after you called the Figure in the text to avoid the situation with Fig 3 and 4, 5, 6 and 7 where Figure appears long paragraph after it was cited making the reading uneasy.
Questions
Q1
Line 75, you indicates that you use Final Analysis (FNL) Operational Global Analysis data [16] and forecast grids, which have 75
a horizontal resolution of 1.0° × 1.0° and a temporal resolution of 6 h ...
It means that on D01 you interpolating 1deg = 100km to 9km, would not have been better to use a forecast data GFS of 0,25deg. Please precise the rationale for this choice.
Q2
Ocean updating. Could you precise where the SST updating comes from meaning what the origin of the ocean data is.
Q3
Would you consider that MCC a typical flash flood in the region of something exceptional ? meaning that its drivers are well established ?
Q4
Does the monsoon period play any role in this MCC.
Specific comments
Structure
Abstract
Start your intro indicating that flash flood is a big issue as it cause huge damage and life lost. Then stress out that forecasting flash flood is not easy because it is connected to convection systems that evolve rapidly and need a high resolution forecasting system. In addition, forecast time is short which limits emergency action.
Indicate that MCS
Then insist that consistent description/modelling of MCS case study is key issue to improve our understanding about it. Indicated that there are few studies about such cases in that region which stress out the novelty of the study ... you may also indicate that your forecasting strategy is new.
Finally clearly indicates what your new finding compares to other studies in that region such as what triggers MCS heavy rainfall generation.
Precise that you use a CTRL and SST update experiment to investigate the impact of SST on rainfall ()
We investigate the hypothesis that the SST
Introduction
Too short and lack of references
You need to describe previous study on flash floods in the region and also MCS related study in that region too.
You may need to increase the length of your section presenting the Maritime Continent unique climate as well as the limited observation available.
Limited observation ghave impact on the assimilation quality and therefore the initial condition available for WRF.
Figures
Figure 1
Add the unit of the scale on the Figure --> m
Precise that Sulawesi is the largest island in the middle of the picture or add it in text on the plot (may lead to too much text on it)
Figure 2
Figure 2b
Need a y-axis unit --> mm ?
Legend
Rainfall amount recorded by BMKG stations between
Luwu and central Sulawesi (D03) from 10 to 17 July 202
-->
Cumulative rainfall amount recorded at Luwu BMKG stations (blue line) and average cumulative rainfall amount computed on the D03 domain from 10 to 17 July 202
Figure 2c
Indicate that the average or maximum daily rate as the unit is in mm/day
Also indicate that an interpolated stations map
Figure 4
Figure 4a Black Body Temperature (TBB) cloud-top height ??
Is that a Top of Cloud temperature ?
Add the unit --> T(K)
Figure 4b
Add the unit (mm) top of the scale color
Tables
Table S1
Please move that table from supplementary to the article. WRF configuration is a very important information for article readers as it potentially helps to improve models for similar regions. Precise how the parametrization was established. Does that come from other studies ?
Lines
Line 24
Define LST before using it
Line 168,
move the ). to Line 163
Line 100 Precise if the rainfall is an average per day
13 to 16 July 2020 (90–120 mm d −1 )
-->
13 to 16 July 2020 (Average 90–120 mm d−1)
Line 11 Are you referring to the SST anomaly ?
Figure 3c
-->
Figure 3b
Line 249
Precise why you refer to data assimilation here while you don't seem to use WRFDA. Would you suggest that may improve the model results ?
Author Response
Dear Reviewer,
Thank you for giving us the chance to make the first revision to our paper manuscript. We appreciated your comments. We have tried our best to follow constructive suggestions from the reviewer and yourself. We have sent you the second revision of the paper manuscript in a separate file.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The work is very interesting, but some parts need to be improved a lot.
First, the graphic resolution of many of the figures is too low. It would also be advisable for the north and the scale to be explicitly indicated in the figures showing portions of the territory. Also in figure 6, the length scale on the abscissa is missing and it is not clear where points A and B are located.
As regards the phenomenon studied and its modelling, figures 1, 5, 7 seem to show results provided by the model, while figures 2, 3, 4, 6 report experimental data. No figures for comparison are present. It would be very important to have some figure or table showing the agreement (or disagreement) between the experimental data and the model, to have a quantitative measure of the validity of the developed numerical model.
Even about the development of the model, the information you provide is too scarce. WRF is a complex program and requires a lot of input data (in addition to the calculation grids) to provide reliable results. In your work, there is only the computational domain in figure 1 and table 1 in the additional material. I think it might be useful to deepen this part by inserting a special section, if you prefer, in the additional material.
Author Response
Dear Reviewer,
Thank you for giving us the chance to make the first revision to our paper manuscript. We appreciated your comments. We have tried our best to follow constructive suggestions from the reviewer and yourself. We have sent you the first revision of the paper manuscript in a separate file.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The authors responded to all questions asked by the reviewer. The current manuscript was improved in clarity.
Author Response
Response by Authors (hereafter Response) #1:
The authors thank the Reviewer 1 for the comment. This indicated that all the suggestions from Reviewer 1 have been accommodated in the previous revision so that there is no need for any improvements in the manuscript.
Author Response File: Author Response.pdf
Reviewer 2 Report
Please, carefully check the style of the English language, both using tools available on the net (such as Grammarly) and with the help of native speakers.
Page 1, lines 13 and 15 "modelling" instead of "modeling"
Page 2, lines 53 and 65 "and the Arafura Sea" instead of "and Arafura Sea"
Page 2, line 56 "cumulus congestus" instead of "cumulus‐congestus"
Page 2, line 75 "may trigger flash floods" instead of "may triggered flash flood "
Page 2, line 79 "kilometres" instead of "kilometers"
Page 2, line 80 "Luwu is located" instead of "Luwu located"
Page 2, line 81 "case that represents" instead of "case represents"
Page 2, line 82 "modelling" instead of "modeling"
Page 3, line 87 "over eastern Indonesia" instead of "over the eastern Indonesia"
Page 3, line 88 "method to investigate the" instead of "method to investigates the"
Page 3, line 98 "The centre of the" instead of "The center of the"
Page 3, line 109 "simulated selected episodes" instead of "simulated a selected episodes"
Page 3, lines 109-110 "rainfall events during 13‐14 July 2020 associated with a flash flood over the Luwu region," instead of
"rainfall event during 13‐14 Juli 2020 associated with a flash‐flood over Luwu region,"
Page 3, line 111 "forecast outputs are" instead of "forecasts output are"
Page 4, line 117 "Colour shading" instead of "Color shading"
Page 4, line 122 "modelling" instead of "modeling"
Page 4, line 128 "configuration " instead of "configuratioan "
Page 4, line 129 "The detailed namelists" instead of "The detail namelists"
Page 4, line 130 "are described in the supplemental file." instead of "described in supplement file."
Page 5, line 136 "(CTL), and" instead of "(CTL); and"
Page 5, line 149 "image represents the top of" instead of "image which represents top of"
Page 7, line 188 "An MCC is" instead of "A MCC is"
Page 7, line 192 "water vapour" instead of "water vapor"
Page 8, line 197 "the location of the points" instead of "the points location"
Page 9, lines 216-217 "represent the Luwu region, whereas the vertical solid line denotes the east coastal" instead of
"represented Luwu region, whereas vertical solid line denoted as east coastal"
Page 9, line 220 "morning of 14 July" instead of "morning 14 July"
Page 9, line 229 "landward on 13 July" instead of "landward at 13 July"
Page 10, line 235 "started on 13 July" instead of "started at 13 July"
Page 10, line 240 "comparing rainfall" instead of "comparing between rainfall"
Page 10, lines 244-245 "Those initial times two hours early compared to the rainfall observed." 31 / 5000
Risultati della traduzione
This sentence is incomprehensible. Please rephrsase.
Page 10, line 246 "the updated SST scenario was better than" instead of "the updated SST scenario better than" (or, maybe, rephrase?)
Page 10, line 252 "between the SST scenario" instead of "between SST scenario"
Page 10, Fig. 6 insets are both labelled with (a)
Page 10, line 257 "oversea" instead of "over sea"
Page 11, line 271 "whereas the SST scenario" instead of "whereas SST scenario"
Page 11, lines 275-276 "which is described by a strong propagation of convection systems"
instead of "which described by strong propagation of convection system"
Page 11, line 277 "over the Luwu region" instead of "over Luwu region"
Page 11, line 283 "convection was still weak" instead of "convection still weak"
Page 12, line 295 "run; (d)" instead of "run; and (d)"
Page 12, line 303 "a cold pool developed in a large area over the Luwu" instead of "cold pool developed in large area over Luwu"
Page 12, line 304-306 "over the ocean (B; Eq, 126°E) under back‐building mechanism. This mechanism seems strongly influenced by the moistening of the boundary"
instead of "over ocean (B; Eq, 126°E) under the back‐building mechanism. This mechanism seems strong influenced by moistening of boundary"
Page 13, line 320 "cross-sections" instead of "cross sections"
Page 14, line 332 "this long‐lasting" instead of "the long‐lasting"
Page 14, lines 333-336 "has a small contribution in controlling the large system of MCCs due to the slow-motion and quasi‐stationary of the convective system. However, the role of monsoons is to provide an environment to support the stationary of the warm front"
instead of
"has small contribution in controlling the large system of MCCs due to the slow motion and quasi‐stationary of the convective system. However, role of monsoon is providing environment to support the stationary of warm front"
Page 15, line 338 ans 346 "vapour" instead of "vapor"
Page 16, lines 359-360 "which is consistent with previous studies [30–33]," instead of "which found consistent with previous studies [30–33]"
Page 16, line 363 "region, described in a previous study [14]." instead of "region described in previous study [14]."
Page 16, line 366 "The long-lasting MCCs" instead of "The long lasting MCCs"
Page 16, line 374 "in the WRF model" instead of "in WRF model"
Page 16, line 375 "helpful in producing" instead of "helpful producing"
Author Response
Response by Authors (hereafter Response) #2:
The authors thank the Reviewer for the comment. To accommodate the suggestions, we changed all the sentences as Reviewer suggestions and further delivered the manuscript to the language editing team of Atmosphere journal. We explained the detail changed of the final version (after edited by Language Editing Team) as below:
Page 1, lines 14 and 16: modelling
Page 2, lines 50-51 and 55-56: the Arafura Sea
Page 2, line 58: cumulus congestus
Page 2, line 77: may have triggered (changed by Language Editing team)
Page 2, line 81: kilometres
Page 2, line 82: Luwu is located
Page 2, line 84: ideal case that represents (changed by Language Editing team)
Page 2, lines 85-86: modelling
Page 3, line 90: over eastern Indonesia
Page 3, line 91: method to investigate
Page 3, line 101: The center of the
Page 3, line 113: simulated selected episodes
Page 3, lines 113-114: heavy rainfall events from 13 to 14 July 2020 associated with a flash flood in the Luwu region, Sulawesi, Indonesia
Page 3, line 115: forecast outputs were evaluated
Page 4, line 121: Color shading (changed by Language Editing team)
Page 4, line 126: modelling
Page 4, line 132: configuration
Page 4, line 133: The detailed namelists
Page 4, line 134: are described in the supplemental file
Page 5, line 140: (CTL),
Page 5, line 153: The IR1 image represents the top-of-cloud temperature
Page 7, line 192: An MCC is
Page 7, line 196: water vapor (changed by Language Editing team)
Page 8, line 201: the location of the points
Page 9, lines 204-205: The black dashed box indicates the Luwu region (120°E–121°E). The vertical solid line represents the east coast.
Page 9, line 224: morning of 14 July
Page 9, line 233: landward on 13 July
Page 10, line 239: started on 13 July
Page 10, line 244: comparing simulated and observed rainfall
Page 10, lines 249-250: Those initial rainfall times were simulated two hours early compared to the observed rainfall.
Page 10, lines 250-251: However, the simulated rainfall in the updated SST scenario performed better than the CTL in capturing the maximum intensity, and significantly increased the rainfall by ~5 mm.
Page 10, lines 257: between the SST scenario
Page 10, Figure 6: we changed labeling (a) to (b) as follow:
Page 10, line 262: over sea (changed by Language Editing team)
Page 11, line 276: whereas the SST scenario
Page 11, lines 280-281: which are described by a strong propagation of convection systems
Page 11, line 282: across the Luwu region
Page 11, line 288: convection was still weak
Page 12, line 300: run; (d)
Page 12, line 308: a cold pool developed in a large area over the Luwu
Page 12, line 309-311: over the ocean (B; Eq, 126°E) under a back-building mechanism. This mechanism seems to be strongly influenced by the moistening of the boundary
Page 13, line 325: cross-sections
Page 14, line 337: this long‐lasting
Page 14, lines 338-340: has a small contribution in controlling the large system of MCCs due to the slow-motion and quasi-stationary characteristics of the convective system
Page 15, line 344 and 352: vapor (changed by Language Editing team)
Page 16, lines 365-366: which is consistent with previous studies [30–33]
Page 16, line 369: region, described in a previous study [14].
Page 16, line 372: The long-lasting MCCs
Page 16, line 380: in the WRF model
Page 16, line 381: helpful in producing
Author Response File: Author Response.pdf
