Spatial Heterogeneity in Dead Sea Surface Temperature Associated with Inhomogeneity in Evaporation
Round 1
Reviewer 1 Report
The manuscript reported a study of Diurnal Cycle of Surface Temperature for the Dead Sea and Adjacent Land Areas. The METEOSAT-based sea monthly surface temperature and the observations from two local meteorological stations are used to support the study. The diurnal cycle, ranges and extreme values of the Surface Temperature were investigated at different time scales. The conclusions were supported by a solid data analysis.
Figure 8 c and d show the temperature difference. Elaboration is needed on how the surface heat flux from land to sea is determined by the temperature gradient between LST over remote land areas, and how the surface heat flux lead to a changed pattern of SST.
Author Response
See our reply to Reviewer #1's comments in the attached file
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Abstract
There is a significant improvement of the abstract from the first version.
Introduction
This chapter is now more coherent and improved.
Material and Methods
This chapter is now much more clear and improved.
Results
This chapter is now much more clear and improved. The authors added new graphic (and sub-section).
Discussion
Again, the text was changed in such as way as to make their results clearer (and in comparison with other authors results). They were also able to clearly emphasise now the novelty on their research work. It is obvious the amount of work made which is quite impressive.
Conclusions
Overall, the text is now significantly improved, conclusions are well addressed based on te research results and also highlight the importance of this work to a region such as the Dea Sea.
Author Response
See our reply to Reviewer #2's comments in the attached file
Author Response File: Author Response.pdf
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
My comments and suggestions are in the joined the pdf document
Comments for author File: Comments.pdf
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 2 Report
The manuscript reported a study of Diurnal Cycle of Surface Temperature for the Dead Sea and Adjacent Land Areas. The METEOSAT-based sea monthly surface temperature and the observations from two local meteorological stations are used to support the study. The diurnal cycle, ranges and extreme values of the Surface Temperature were investigated at different time scales. The conclusions were supported by a solid data analysis. A few suggestions to improve the manuscript are: a) describe the accuracy of the monthly SST from the METEOSAT; b) it will reveal more information if the data from Tables 1 and 2 can be converted to graphic plots; c) It was stated that “Spatial heterogeneity in evaporation over the Dead Sea was retrieved from non-uniformity in METEOSAT-based sea surface temperature (SST) from 2005 to 2015”. It will he helpful to show the spatial pattern of evaporation for this region in a map; d) The spatial resolution of the METEOSAT SST is about 5km. Describe if there is any special processing done for the pixel with a mixture of land and sea.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
This is a potentially interesting study highlighting spatial and temporal differences in remotely sensed SST at various locations on the Dead Sea (and adjacent land areas), and the authors attempt to relate these to spatial variations in evaporation rate. Unfortunately, I don’t think the study accomplishes these objectives for a number of reasons:
- The theoretical basis for relating the diurnal timing of solar radiation and SST is overly simplified, since it does not account for three critical components in the lake energy balance: a) incoming longwave radiation (which the authors acknowledge), b) outgoing longwave radiation from the water surface, and c) heat storage within the lake water column. If one also ignores latent and sensible heat flux for the time being, one would expect the lake heat storage term to maximize when net radiation (Rnet) is maximum (i.e., not when solar radiation is maximum). Even then, assuming a well-mixed upper water layer, the maximum SST would occur when Rnet begins to cross over 0 and become negative (i.e., not when Rnet is maximum). The authors do not discuss these necessary details and also do not attempt to include incoming and outgoing longwave radiation in their analysis, resulting in a very weak argument for making their case.
- I did not see discussion anywhere of potential land contamination of the eastern and western lake pixels, which appears to be possible given the map in Figure 1. If this is occurring, it could easily cause the eastern and western “lake” pixels to look a bit more like “land,” thereby influencing the analysis and, ultimately, the conclusion that variations in SST are due to spatial variations in evaporation (rather than pixel contamination).
- Related to point #2, what about advection of heat from land to sea, causing an increased downward sensible heat flux to the lake for the eastern and western pixels? Would this not also lead to higher SSTs near shore as opposed to the pixels in the middle part of the lake? The authors seem to try and address this question a bit with their air temperature analysis, but the presentation is very hard to follow.
- No satellite-based or buoy-based observations of wind speed are presented to back up the claim that evaporation rates are greatest over the center of the Dead Sea. Why would one expect this to be the case? Even without observations, what would be the logical explanation or “cause” of higher wind speeds over the middle of the lake? And what about humidity gradients? Wouldn’t one expect the atmospheric vapor pressure to be higher near the middle of the lake, which would then cause lower evaporation rates? There seems to be very little reason to expect the evaporation pattern that the authors suggest, as well as no observations to support their hypothesis (other than SST patterns, which I’ve argued above are based on an oversimplified energy balance).
- Overall, the writing and presentation are quite hard to follow. Lots of details about the timing and diurnal cycle of solar radiation and SST, for example, but with relatively little numerical analysis or synthesis (e.g., via a rigorous surface energy balance equation). I find all the many written arguments very hard to follow, and not backed up by any sort of rigorous analysis. As a result, I am not at all convinced that a spatial variation in evaporation exists on the Dead Sea as the authors try to argue. The conclusions simply aren’t backed up by any sort of convincing analysis.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 4 Report
Introduction:
A few observations
Line 51 - please correct "patters" to "patterns"
Line 65. You cannot present figure 1 before referring to it first in the text. You do it for the first time only in the methods section (line 90)
Line 71 - "Tw, Tm, Te designate SST averaged over the western, middle and ..." - you should not start a sentence with an abbreviation.
Line 72 ..."eastern Dead Sea respectively" Missing a comma "eastern Dead Sea, respectively"
Line 72 - TLw1, TLw2, TLe1, TLe2 designate LST averaged over land areas ..." - you did not explain before what LST stands for. Please explain in Figure 1 legend because you only provide this information later in the text on line 79 so it is not advisable to present an abbreviation prior to explaining what this stands for.
Line 73 - The black triangle and square show - for a while I was not able to see where the triangle was in the figure, only realized by trying to find it through the coordinates provided in the figure legend. I would advise extending the map coordinates such as to cover Sdom.
Materials and Methods
Line 90 - "...(Fig. 1). In Fig. 1, we used" maybe change to" ... (Fig. 1). In this figure we used..."
Lines 91 to 97 - "Specifically, columns 1 91 and 2 represent pixels covering land areas to the west of the Dead Sea, while columns 6 and 7 92 represent pixels covering land areas to the east of the lake. Column 3 shows pixels covering the 93 west part, while column 5 shows pixels covering the east part of the lake. Pixels covering the 94 middle part of the lake are represented by column 4. Hereafter Te, Tm, and Tw designate SST 95 over the east, middle and west parts of the Dead Sea. TLe1 and TLe2 designate LST over land 96 areas to the east of the Dead Sea, while TLw1 and TLw2 designate LST over land areas to the 97 west of the lake." - this should be deleted. You have this explanation in the legend of figure 1, you do not need to duplicate this information.
line 106 -" of the Dead Sea respectively." Change to of the Dead Sea, respectively.
Line 109 - You refer to Table 1 in the methods section, then this only appears in a few pages later (line 196) on the results section! This cannot be. This should appear in the methods section then.
Results
No need to repeat again: line 77 - "Using METEOSAT products, we analyzed, separately, the diurnal cycles of SST over the 117 east, middle and west parts of the Dead Sea, as well as those of surface temperature over the 118 adjacent land areas"
No need to say several times in the results section "(see Discussion for details). " or "(See Section 4. 157 Discussion for details)" or ("see Discussion")
The results are repetitive and extensive.
Discussion
Line 367 - "(DTR) (the difference between daily maxima and minima)" - you have already defined what DTR is previously. Please do not repeat the same things over and over again.
Parts of the discussion could actually be included in the results. I would expect to see this chapter delve into the meaning, importance, and relevance of your results. I also expected to see how your work relates to your literature review and making an argument in support of your overall conclusions, but this is not what I have read.
Conclusions:
Again, some aspects were repetitive. Once again, I expected to see a clear summary reflecting all the research made and maybe some recommendations for future work on the topic and how this new knowledge can contribute to understanding better Dead Sea ocean/atmosphere processes.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
