Studies of FY-3 Observations over the Past 10 Years: A Review

Round 1

Reviewer 1 Report

This review paper summarizes about 10 years research by the author on analyzing Chinese instruments for their value in numerical weather prediction.  Overall, the paper is of good quality, and worthy of publications. I have the following minor suggestions to improve it for publication:

 

1.  Lines 32-35 should be removed. I don't think this is appropriate for an international journal.
2. Line 83. Change "presents" to "prevents".
3. Lines 85-86.  By matrix vector multiplication, do you mean: P^fH^T? Perhaps this could be clarified.
4. Line 87: The meaning of observation operator should be defined, as this paper is likely for a more general audience.
5. Line 91: This statement is not clear. Do you mean: 

   This is not clear. Do you mean "Observation can only be used in weather prediction through data assimilation"?  Please make this more clear.

6. Line 94: remove "the" before satellite.
7. Line 118: change "who" to "which".
8. Line 119: Please define the acronym "GRAPES".
9. Line 166: Please change "researches" to "research". (research is the plural of research!).
10. Line 215: Change "sum" to "difference"
11. Line 228: Remove "then".
12. Lines 229-231: 

    I want to make sure I understand how the comparison is being made? I'm assuming that you are not comparing these directly, but rather computing O-B for each instrument, where  B is something like ECMWF reanalyses? Is this correct? It is not quite clear.

13. Line 250: You mention NCEP reanalyses here. Are you using these throughout for the O-B calculations? Please be specific about when you are using this, and when you are using another model or forecast for B.
14. Line 256: Is there a reference that confirms this?
15. Line 288: Can you describe the causes of striping noise? References?
16. Line 297: Model or Reanalysis (NCEP or ?). Please be specific.
17. Line 355: Do you really mean "popular", or do you mean "successful"?
18. Line 413: The caption here is cut off. Also, please define the acronym "GEC" in the text.
19. Line 444: Again, is this NCEP reanalysis, or another model source?
20. Line 445: Is this still channel 1? and is this a window channel? Why was it chosen for cloud detection?
21. Line 500: Change "weighing" to "weighting".
22. Line 574: Change "researches" to "research".

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

See attached review file named remotesensing-1098133-peer-review-v1_ReviewComments.pdf.

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Please refer to attached PDF file.

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

General Comments:

The Reviewer appreciates the line-by-line responses to their questions and comments by the author. They also are thankful to the author for acknowledging the value of the review. Most comments have been resolved satisfactorily, but a few still remain. These few are detailed below.

Again, my recommendation is to accept this article after my questions, and list of suggested revisions, have been carefully considered and addressed by the author.  

Line-by-Line Comments and Questions:

Line 15-16 – Recommend to change from … “how well the FY-3 data in aspects described above are known.” to “… how well the FY-3 data characteristics and errors listed above are known.”

Line 125-126 – For clarity, recommend to change “… data thinning in horizontal (DTH) and vertical (DTV) directions or spectral 125 (DTS) parameter space.” to “… and data thinning in horizontal (DTH) and vertical (DTV) directions and/or the spectral (DTS) parameter space.”

Line 128-131 – The Reviewer thinks they understand the point now. When reanalysis is created with data that have been through careful quality control and screening, it can be used to detect errors with satellite data that have not.

Line 224-231 – The Reviewer sees that they were confused here during Review Round 1. They now see that the word “temperature-dependent bias” in Line 226 should be “latitudinal-dependent bias”, since it is a function of the j (latitude). They thought that the author meant a physical instrument temperature related bias. So, “temperature-dependent bias” in Line 226 should be changed to “latitudinal-dependent bias”.

If the author’s intention is to associate latitudinal bias with average scene temperature-dependent bias, then they need to state this. Otherwise nothing else needs to be said.

Now that the Reviewer understands that the “temperature-dependent” analysis is not that of instrument temperature dependence, but of latitudinal dependence, it is recommended to delete the following sentences:  “An implicit assumption to separate scan- and latitudinal-dependent biases is that MWTS brightness temperature is not a function of scan position. This assumption is made considering MWTS’s coarse resolutions (~50 km at nadir and ~100 km at large scan angle)”

Line 351 “found” instead of “founs”

Figures 6 and 7  - The colorbars are not centered under the figures, and the beginning of the text below Figure 7 is clipped. Is this an issue with creating the PDF?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf