Outdoor Air Temperature Measurement: A Semi-Empirical Model to Characterize Shelter Performance
, Pascal Kéravec 2,3, Benjamin Morille 2,4, Erwan Bocher 1, Marjorie Musy 2,5,6 and Isabelle Calmet 2,3,*Round 1
Reviewer 1 Report
The paper presents an improved semi-empirical model to characterize weather stations' shelter performances in term of temperature bias due to the influence of the shield itself, and the microclimate inside the shelter, on the sensor.
The paper tackles a very interesting problem for both the thermal measurements and meteorological communities. The paper is well written, with a thorough background of literature research behind it, altough sometimes mis-quoted.
The model presented claims to improve the estimation of temperature biases due to the influence of shields on sensors. However, two of the three energy balance equations used to derive the model present an error. The problem with equations 6 and 7 is that the authors mix up volume fluxes of air inside the shields (by multiplying cross section by speed) with a mass heat capacity - this is evident by performing dimensional analysis. The authors should have used the volumetric heat capacity of air or, conversely, multiply the volume flux of air by air density to get an air mass.
As this is a very major point, since the model is based on these energy balance equations, I wonder whether the paper should be rejected in this current form to give time to the authors to redo all the necessary calculations, then resubmit. If that's the case, I will be interested in re-review the final article.
I have a (non-exhaustive) list of other minor issues. It seemed pointless to go through all the paper given the error in energy balances.
line 3: "evaluate" instead of "assess"
line 6 and elsewhere: Organization, not Society.
line 69: Maybe it's my fault, but I didn't find this statement in the cited work. Maybe the authors referred to Lin et al 2001 [9]?
line 88: "themselves"
line 130: again, I couldn't find the quote in the cited work. In this case, at last, the topic is correct. If the line in quotation marks is not a direct quote from the text, please remove the marks.
line 157: "Objective", not "objectives"
line 169: I would say "calculated", not "performed"
line 236: Pt100's are not thermistors. They are platinum resistance thermometers.
line 239: While the usage of "error" and "uncertainty" in this paper is remarkably correct, in this instance uncertainty should be used.
line 276: So basically what is considered as best screen is not so good. Did you try to use other screens as references, maybe more consistent between them? I'm really concerned about using the average of these two screens as a reference.
line 303: How many values of wind speed < 1 m/s were recorded? Maybe a windrose plot would be interesting in order to understand the ratio of low versus high speed winds.
Figure 2: I'm really not sure the map is necessary. Maybe a picture of the site would be more interesting.
Figures 5,8,9,10,11,12,13,14: Axis labels are barely legible. Please provide better quality figures.
Table 3: I'm not sure I understood the sampling conditions for wind. "An average of the last 2 min recorded every minute" means a moving average? Why this choice when for other variables normal averages were computed? Was the wind speed averaged vectorially?
Author Response
Dear reviewer 1,
You will find three documents on the plat-form :
- a point by point answer to each of your comment
- a new version of the article
- the new version of the article where each modification between the first and the new version has been highlighted. This version is called the "revised version".
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Please see attached notes
Comments for author File: Comments.pdf
Author Response
Dear reviewer 2,
You will find three documents on the plat-form :
- a point by point answer to each of your comment
- a new version of the article
- the new version of the article where each modification is highlighted. This version is called the "revised version".
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Thanks for providing an improved version of the manuscript so quickly. Some minor comments on my part, plus one comment which I would not qualify as "major" but is a little more than "minor":
- line 399: as far as I know, time constant of a temperature sensor is defined as the time it takes a temperature sensor to change 63.2 % (not 67 %) of the total difference between the initial and the final body temperature. It is not "xx % of the final temperature value", rather "xx % of the total change in temperature". It's quite a lot different. Please explain and/or rectify.
Minor comments:
- Some of the units in the lists after the equations are given with the division sign "/", others with the negative exponentiation. For uniformity's sake, one of the two should be chosen. Please check the journal guidelines.
- line 198: "time derivative of the temperature of the system".
- line 385: the sentence should be either in the text or in the picture caption, not both.
- line 387: I would introduce the comment on the particular conditions of figure 10 better. Right now you go from commenting the regression coefficient to the analysis of Figure 10 very abruptly.
- Figure 10-11: this is completely at your digression, but being color-blind I have troubles reading the different lines. It would be great if you could also set different lines bodies (solid, dashed, etc).
- line 480: I think it should be "take into ACCOUNT".
- line 405: "the results... ARE"
Author Response
The authors would like to thank again reviewer 1 for his careful review. We have taken every comments into account. You will fin attached three documents :
- one containing the answer to each of your comment
- one containing the revised version of the article highlighting the modifications brought since the previous version
- one containing the revised version (new version).
Author Response File: Author Response.pdf
