Accepted subject to minor revisions - see Reviewer's suggestion below.

Thanks for publishing your data with ESSD!

------------------- Reviewer's Suggestion ----------------------

I only have one suggestion. I thank the authors for adding detail on what a virtual station is. The location in which this has been inserted feels like it has just been plopped into the text. Could I suggest that content be moved so that the paragraph page 4 near line 10 reads: ".... opportunistic exploitation of virtual stations (VSs) on the world's largest rivers specifically suited for the needs of global hydrological applications. GRRATS uses the VS as its fundamental organizational element. VSs are locations where ground tracks of exact repeat altimetry mission orbits cross rivers, enabling the development of a time series of water elevation observations. VSs can be thought of much in the same way as an in situ river gaging station, but are entirely derived from remote sensed measurements of river surface elevation. GRRATS is an "Earth.....".