Spatiotemporal Kriging for Days without Rainfall in a Region of Northeastern Brazil
Round 1
Reviewer 1 Report
- All the figures in the manuscript except Figure 5 need improvement. Please use a higher dpi for the figures (please use a standard minimum dpi for quality publications).
- Please define DWR. What is the minimum cut off value for a day to be called DWR? For example many hydro-meteorology studies consider a minimum of 0.2mm/hr as a rain or not.
- Line 93: ‘The historical series….’ is not clear. Please rewrite the sentence.
- Line 108: ‘… to verify the significance of the parameters.’ Which parameters? Please explain.
- Line 132: ‘… resulting in a spatial resolution of …’
- Line 155: ‘… occurrences of drought…’ please give a scientific definition of drought. Are you using a baseline index to define drought? If so, include a reference.
- Line 161: ‘… natural disaster records…’ What are the natural disasters?
- I see that the authors included Figure 8 that shows Spearman correlation between total precipitation and DWR. I still suggest to the authors to include a figure that shows the total precipitation in each year to accompany Figure 3.
- Please fix Figure 4 y-axes labels. There are ‘?’ on the y-axes labels.
- ‘abs(error)’ please fix Figure 6’s legend.
Author Response
The authors are grateful for the valuable contributions of the reviewer. A point-by-point response to their comments follows.
- All the figures in the manuscript except Figure 5 need improvement. Please use a higher dpi for the figures (please use a standard minimum dpi for quality publications).
We made adjustments to all figures: we increased the fonts and considered 1000 dpi's.
- Please define DWR. What is the minimum cut off value for a day to be called DWR? For example many hydro-meteorology studies consider a minimum of 0.2mm/hr as a rain or not.
The dataset used in this manuscript was obtained by the Executive Agency for Water Management of the State of Paraíba (AESA). The original dataset refers to the daily rainfall recorded at each of the rainfall stations.
We consider a day without rain, when there was no record of rainfall on the day (0 mm). This information was included in the manuscript.
- Line 93: ‘The historical series….’ is not clear. Please rewrite the sentence.
The sentence was rewritten.
- Line 108: ‘… to verify the significance of the parameters.’ Which parameters? Please explain.
Parameters related to independent variables. At the end of this sentence we improve the explanation.
- Line 132: ‘… resulting in a spatial resolution of …’
We include this term.
- Line 155: ‘… occurrences of drought…’ please give a scientific definition of drought. Are you using a baseline index to define drought? If so, include a reference.
We insert a reference putting the definition of “dry”.
- Line 161: ‘… natural disaster records…’ What are the natural disasters?
We insert the reference “CEPED - University Center on Studies and Research on Disasters. Brazilian Atlas of Natural Disasters: 1991-2012. 2013, Paraíba, 105” which is the Brazilian Atlas of Natural Disasters, being mentioned: Droughts, Floods, Inundations, Flooding, Windstorm, Hail and Erosion.
- I see that the authors included Figure 8 that shows Spearman correlation between total precipitation and DWR. I still suggest to the authors to include a figure that shows the total precipitation in each year to accompany Figure 3.
We insert a new figure (Figure 9) with the total annual rainfall densities for the different mesoregions.
- Please fix Figure 4 y-axes labels. There are ‘?’ on the y-axes labels.
We made the correction.
- ‘abs(error)’ please fix Figure 6’s legend.
We made the correction.
Reviewer 2 Report
This paper describes spatiotemporal characteristics of drought in north-eastern region of Brazil. The analysis method is conventional and not new but it is sound. Numbers of days without rain (DWR) were used to characterized the drought. DWR characteristics in the interested region is novel.
Minor comments:
1) The importance of the DWR instead of rain should be described more. What are the differences and advantages over rain statistics? This may be important to enhance the meaning of this paper.
2) P1 L23: Something needed before “Expected”.
3) P3 Fig.1: The figure is not clear.
4) P7 L204: ... more related to space than to time: Space and time are different parameters, and the results depends on the units. So, it is difficult to say “... more ...”.
Author Response
The authors greatly appreciate the valuable contributions of the reviewer. Below are the point-by-point responses.
1) The importance of the DWR instead of rain should be described more. What are the differences and advantages over rain statistics? This may be important to enhance the meaning of this paper.
We inserted more excerpts with quotes and references about the droughts throughout the manuscript.
2) P1 L23: Something needed before “Expected”.
We rewrite the sentence presented in this line.
3) P3 Fig.1: The figure is not clear.
We have improved the resolution of this image.
4) P7 L204: ... more related to space than to time: Space and time are different parameters, and the results depend on the units. So, it is difficult to say “... more ...”.
When we comment on this, we are referring to the fact that the variability of rainfall, quantified by the variogram, has higher levels in relation to temporal than spatial distances.
Reviewer 3 Report
The article is very interesting and the topic has been approached in an innovative way, however there are mainly formal problems in the structure of the article
-The introduction cannot only be about the Brazilian territory, but must be a state-of-the-art analysis of the various topics of climate change in the world.
Regarding drought in the world i recommend to study and cite some interesting articles:
Mukherjee, S., Mishra, A., & Trenberth, K. E. (2018). Climate change and drought: a perspective on drought indices. Current Climate Change Reports, 4(2), 145-163.
Cook, B. I., Mankin, J. S., & Anchukaitis, K. J. (2018). Climate change and drought: From past to future. Current Climate Change Reports, 4(2), 164-179.
Hoffman, M. T., Carrick, P. J., Gillson, L., & West, A. G. (2009). Drought, climate change and vegetation response in the succulent karoo, South Africa. South African Journal of Science, 105(1), 54-60.
Regarding crop and climate change i recommend to study and cite some interesting articles:
Ray, R. L., Fares, A., & Risch, E. (2018). Effects of drought on crop production and cropping areas in Texas. Agricultural & Environmental Letters, 3(1), 170037.
Gentilucci, M., Barbieri, M., & Burt, P. (2018, November). Climate and territorial suitability for the Vineyards developed using GIS techniques. In Conference of the Arabian Journal of Geosciences (pp. 11-13). Springer, Cham.
Iqbal, M. S., Singh, A. K., & Ansari, M. I. (2020). Effect of drought stress on crop production. In New frontiers in stress management for durable agriculture (pp. 35-47). Springer, Singapore.
Bodner, G., Nakhforoosh, A., & Kaul, H. P. (2015). Management of crop water under drought: a review. Agronomy for Sustainable Development, 35(2), 401-442.
Regarding SPI i recommend to study and cite the following interesting articles:
Sahoo, A. K., Sheffield, J., Pan, M., & Wood, E. F. (2015). Evaluation of the tropical rainfall measuring mission multi-satellite precipitation analysis (TMPA) for assessment of large-scale meteorological drought. Remote Sensing of Environment, 159, 181-193.
Tirivarombo, S., Osupile, D., & Eliasson, P. (2018). Drought monitoring and analysis: standardised precipitation evapotranspiration index (SPEI) and standardised precipitation index (SPI). Physics and Chemistry of the Earth, Parts A/B/C, 106, 1-10.
Livada, I., & Assimakopoulos, V. D. (2007). Spatial and temporal analysis of drought in Greece using the Standardized Precipitation Index (SPI). Theoretical and applied climatology, 89(3), 143-153.
-results should be one paragraph and discussions another paragraph, please divide them. In particular the discussion is completely absent, you must compare the methods you have analysed and the results obtained with the current scientific literature.
Author Response
The authors are grateful for the valuable contributions.
As a reviewer's suggestion, we added paragraphs about drought in a broader context. Inserting the references that were indicated.
We also did the same on the effects of drought on agricultural production.
We put the references, as suggested, to the SPI.
Paragraphs with more discussions have been added. In particular, on the trend and on the drought rates.
Again, we thank you for the suggestions that made the manuscript present improvements.
