Review of

On Some Aspects of Air-sea Interaction Processes of the Tropical Indian Ocean using Satellite Data

Submitted to Remote Sensing of the Environment

by M. R. Ramesh Kumar and P. Schluessel

This paper describes an analysis of three years of NOAA AVHRR and DMSP SSM/I data from the Indian Ocean region. Various relationships, annual cycles, and correlations are examined for SST, wind speed, latent flux, and column integrated water vapor (W). The W is treated as a surrogate for deep convection.

In my opinion the paper has significant flaws and should be rejected. On the plus side, the basic information conveyed in Figs. 5-12 is interesting. However, I am not sufficiently well versed in the literature to know if this is new stuff. Most of the body of the paper consists of wordy descriptions of these figures ('the curve goes up, then it goes down, etc'), which don't add anything since my eye tells me the same thing. The long descriptions of correlation analysis with weak and unsubstantiated speculations about physical processes is confusing and contradictory. Example: 'Evaporation was found to suppress convection on short term periods over the Indian Ocean except over CAS and EEIO'. Does this mean anything?

A few other major points of criticism:

1. I don't see that W is much of a surrogate for deep convection. We know there is a strong annual cycle of precip in the Indian Ocean and Bay of Bengal, yet virtually nothing appears in W.

2. The correlation and lagged correlation analyses seem flawed to me. For example, the authors find values of r of 0.4 99% level for W and SST in EEIO, yet your eye can see virtually no annual cycle in either. I think most of this correlation comes from the fact that there are larger time interannual variations in W that are "leaking" (i.e., converse of aliasing) into the 3 year time band. Perhaps the authors should time taper these signals before computing the correlations. I predict vastly different results with this small change in numerical procedure.

3. The values of E given in this paper are about half what I would expect, at least near the equator. Are these values consistent with other studies?

A few other minor points:

1. The paper could use some polishing of the English syntax by a professional editor.

2. Figs. 2-5 contain the same information as 6-12. Perhaps reduce to a table with mean, median, and standard deviation.

3. Figs 2-5, the parts a-g are apparently ordered bottom to top, whilst in 6-12 they are top to bottom. This is confusing in 2-5 where they are not labeled in any manner.

4. It wasn't clear to me what was meant by 'correlation over monthly time scales'. Does that mean the average was computed for each month and then the time series of 1-month averages were correlated?

Or does it mean that the correlations of the raw time series were computed in blocks of 1 month?