Variation of Local Wind Fields under the Background of Climate Change and Its Impact on Algal Blooms in Lake Taihu, China
Round 1
Reviewer 1 Report
Comments and Suggestions for Authorsl This work presents an interesting and generally very good research on the algal blooms development in Lake Taihu, China by examining time series of wind fields as a primary dynamic mechanism responsible for the algal blooms intensification and expansion. Spatial and temporal distributions of algal blooms are examined based on satellite data and related algal blood coverage indices. The results offer useful data for water environment management towards algal bloom prevention and control and in this frame the paper can be accepted for publication after considering a few minor suggestions in the following.
l In “2. Materials and Methods, 2.1. Study area and data”, line 156 the full term of the acronym RGB should be given.
l In “2. Materials and Methods, 2.4. Numerical simulation method for near surface wind field”, line 230 the full term of the acronym NCEP should be given. The same for RRTM in line 232.
l In “3. Results 3.1. Temporal distribution of algal blooms in Lake Taihul”, line 261, some clarification should be given about frequency, i.e. if it is the number of images or algal bloom days?
l In “3. Results 3.2. Observational facts of near-surface wind speed change” line 289, the minus “-“ is not necessary and should be deleted since decreasing is mentioned in the text.
l In “3. Results 3.2. Observational facts of near-surface wind speed change”. A general observation in this analysis is that for the decline for the wind speed during the 22-year period 2001-2022, possible urbanization effects with any large and tall buildings, or dense new building or other constructions may be prevent the wind power. Therefore, this factor can be very important in evaluating the reasons responsible to the progressively decreasing of wind speed. Wind direction might be also largely influenced in an area of intensively increasing urbanization.
l In “3. Results 3.5. Response of algal blooms to near-surface wind fields”. This title should be numbered as 3.4 instead of 3.5.
l In “3. Results 3.5. Response of algal blooms to near-surface wind fields”. Again, in this session the possible effects in both wind speed and direction of urbanization should be considered and evaluated for the possible contribution in the results.
l In “3. Results 3.5. Response of algal blooms to near-surface wind fields”, line 449, Table 2, some indication is needed in the “mean wind speed” and “Average Temperature” parameters headings if the represent WRF model or real direct observational data.
Author Response
Responses to Reviewer 1 Comments
- Summary
This work presents an interesting and generally very good research on the algal blooms development in Lake Taihu, China by examining time series of wind fields as a primary dynamic mechanism responsible for the algal blooms intensification and expansion. Spatial and temporal distributions of algal blooms are examined based on satellite data and related algal blood coverage indices. The results offer useful data for water environment management towards algal bloom prevention and control and in this frame the paper can be accepted for publication after considering a few minor suggestions in the following.
Response: We feel great thanks for your professional review work on our article. As you are concerned, there are several problems that need to be addressed. According to your nice suggestions, we have made corrections to our previous draft, the detailed corrections are listed below.
- Point-by-point response to Comments and Suggestions for Authors
Comments 1: In “2. Materials and Methods, 2.1. Study area and data”, line 156 the full term of the acronym RGB should be given.
Response 1: We have made modifications based on your suggestions in the revised version (Line 158):
Line 158: water were manually determined in a RGB (Red-Green-Blue) imagery containing……
Comments 2: In “2. Materials and Methods, 2.4. Numerical simulation method for near surface wind field”, line 230 the full term of the acronym NCEP should be given. The same for RRTM in line 232.
Response 2: The full term of the acronym NCEP was given in the previous version (line213) and line 226 in the revised version:
Line 226: the National Center for Environmental Forecasting (NCEP) in the United States.
The full term of the acronym RRTM was given based on your suggestions in the revised version (Line 235):
Line 235: the Rapid Radiative Transfer Model (RRTM) longwave radiation scheme.
Comments 3: In “3. Results 3.1. Temporal distribution of algal blooms in Lake Taihu”, line 261, some clarification should be given about frequency, i.e. if it is the number of images or algal bloom days?
Response 3: We have made modifications based on your suggestions in the revised version (Line 264):
Line 264: Similar to the trend of cumulative area, the frequency (frequency indicates the number of the algal bloom days) of algal blooms in Lake Taihu.
Comments 4: In “3. Results 3.2. Observational facts of near-surface wind speed change” line 289, the minus “-“ is not necessary and should be deleted since decreasing is mentioned in the text.
Response 4: We have deleted the minus “-” in the revised version (Line 292):
Line 292: that the annual MWS decreased significantly at a rate of 0.4 m/s (or 16.9%) per decade.
Comments 5: In “3. Results 3.2. Observational facts of near-surface wind speed change”. A general observation in this analysis is that for the decline for the wind speed during the 22-year period 2001-2022, possible urbanization effects with any large and tall buildings, or dense new building or other constructions may be prevent the wind power. Therefore, this factor can be very important in evaluating the reasons responsible to the progressively decreasing of wind speed. Wind direction might be also largely influenced in an area of intensively increasing urbanization.
Response 5: We agree with you that in addition to climate warming, the increase of ground roughness caused by urbanization and greening may also lead to the changes of wind field. Our study only analyzed the fact that the near surface wind speed changes observed under the background of climate change and the response of cyanobacterial blooms to it, and did not specifically discuss the extent to which climate change caused the decline of wind speed, which is still a very challenging task at present and the focus of our future research. According to your suggestions, we have described this as a limitation of this study and future research focus in the discussion section (Line 550-556):
Line 550-556: In addition, it is generally believed that in addition to the amplified warming in the northern hemisphere, the increased surface roughness/friction (e.g., the urbanization and greening of the earth) is also another important reason for the decline of near surface wind speed [61]. This study only analyzed the fact that the near surface wind speed changes observed under the background of climate change and the response of cyanobacterial blooms to it, and did not specifically discuss the extent to which climate change caused the decline of wind speed, which is also the focus of our future research.
Comments 6: In “3. Results 3.5. Response of algal blooms to near-surface wind fields”. This title should be numbered as 3.4 instead of 3.5.
Response 6: We are really sorry for our careless mistakes. We have made the corrections in the revised version (Line 411):
Line 411: 3.4. Response of algal blooms to near-surface wind fields.
Comments 7: In “3. Results 3.5. Response of algal blooms to near-surface wind fields”. Again, in this session the possible effects in both wind speed and direction of urbanization should be considered and evaluated for the possible contribution in the results.
Response 7: Thank you for your constructive comments and suggestions. We have described this as a limitation of this study and future research focus in the discussion section (Line 550-556): Line 550-556: In addition, it is generally believed that in addition to the amplified warming in the northern hemisphere, the increased surface roughness/friction (e.g., the urbanization and greening of the earth) is also another important reason for the decline of near surface wind speed [61]. This study only analyzed the fact that the near surface wind speed changes observed under the background of climate change and the response of cyanobacterial blooms to it, and did not specifically discuss the extent to which climate change caused the decline of wind speed, which is also the focus of our future research.
Comments 8: In “3. Results 3.5. Response of algal blooms to near-surface wind fields”, line 449, Table 2, some indication is needed in the “mean wind speed” and “Average Temperature” parameters headings if the represent WRF model or real direct observational data.
Response 8: Thanks for your suggestions. We have added explanations in the revised version (Line 452 ):
Line 452: Table 2. Algal bloom area and meteorological data from September 4-7, 2010. The mean wind speed and average temperature were calculated from the observation data from the five national basic meteorological stations arround Lake Taihu.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe reviewed article titled "Variation of Local Wind Field under the Background of Climate 2 Change and Its Impact on Algal Blooms in Lake Taihu, China" addresses the important issue of the impact of climatic conditions and their changes on algal blooms in Lake Taihu in eastern China. Taking into account the negative impact of algae blooms on water quality, the purpose of the research was correctly justified and does not raise any objections. The study uses well-selected research methods to achieve the research objectives. The work was based on carefully selected scientific literature. The structure of the work is unquestionable. The obtained research results are interesting and provide new information on the influence of the wind field on algal blooms.
I have no objections to the reviewed article and I propose to publish the work in its current form.
Author Response
Responses to Reviewer 2 Comments
- Summary
The reviewed article titled "Variation of Local Wind Field under the Background of Climate 2 Change and Its Impact on Algal Blooms in Lake Taihu, China" addresses the important issue of the impact of climatic conditions and their changes on algal blooms in Lake Taihu in eastern China. Taking into account the negative impact of algae blooms on water quality, the purpose of the research was correctly justified and does not raise any objections. The study uses well-selected research methods to achieve the research objectives. The work was based on carefully selected scientific literature. The structure of the work is unquestionable. The obtained research results are interesting and provide new information on the influence of the wind field on algal blooms.
I have no objections to the reviewed article and I propose to publish the work in its current form.
Response：We feel great thanks for your professional review work on our article. You and the other reviewers’ comments are all of great importance to our article. All of these comments have contributed a lot to improve the quality of our article. Thank you very much.
Author Response File: Author Response.pdf
