|Review: Adaptive Thermal Image Velocimetry of spatial wind movement on landscapes using near target infrared cameras|
The authors edited the manuscript and added new information.
However, in my opinion the comparison of A-TIV with the TIV algorithm is still not detailed enough. The authors added a table showing the percentage of vacant cells and the importance of single TIVs to the A-TIV velocity estimate. However, it remains unclear how the different velocity fields agree with the reference data. I encourage the authors to add a figure comparing wind speed and wind and temperature perturbations from TIV and A-TIV and add the numbers for TIV to Table 4.
I think more discussion is needed on the poor estimate of the mean wind speed. While it would be beneficial to have a spatially distributed estimate of wind velocity e.g. for the estimation of ET using energy balance models, the absolute magnitude of wind speed is of course very important too. I find it interesting that in Figure 5 the histograms of the physical and virtual TC arrays agree very well, even though the TC array is mounted 1.5 m above the ground. In the text it is stated that the sonic anemometer is also mounted at 1.5 m height. Maybe the authors could add the comparison of the TC array and sonic anemometer to their scatter plot in Figure 11 and discuss the reasons for the differences in wind speed in a bit more detail.
The authors state in the Discussion p. 25, 362 “However, the histograms show that the distributions are not comparable, which is expected comparing a point measurement to a spatial approach.” The authors should also discuss this aspect a bit more.
Stull, 1988: “Instead of observing a large region of space at an instant in time, we find it easier to make measurements at one point in space over a long time period. …. Thus, the wind speed could be used to translate turbulence measurements as a function of time to their corresponding
measurements in space.” The authors should discuss why this assumption does not hold in this application.
Some specific comments:
P.4, line 113: Did the authors really want to refer to Section 2.5?
P. 5, line 120: Could the authors add the used interval settings for each flight somewhere in the text or e.g. Table 1?
P. 5, line 140: In my opinion, this sentence belongs to 2.1 since it gives information about parameters used in the TIV algorithm, which are not specific to the A-TIV algorithm.
P. 7, line 143: The height of the sonic anemometer should be added to Section 2.3.
P. 11, line 200: To which frequency were the other experiments subsampled?
P. 12, line 209: I do not understand why the output frequency necessarily has to be 2 Hz due to the ten second windows in the time series.
P. 14, line 272: Reporting a p-value > 0.95 is not very common.
P. 14, Figure 5: I again encourage the authors to add legends to their plots where needed.
P. 18, line 281: Did the authors really want to refer to Table 1 here?
P. 18, Table 4: The mean TIV speed should be added here too.
P. 23, line 309: The wheat stubble alters the wind profile and this also affects the exchange of heat between the surface and the atmosphere.
P. 25, line 377: This sentence is not clear to me.
P. 26, line 378: I don’t really see that Figure 11 supports this claim.