Hello- Ron Stouffer passed your mail on to me regarding your proposed netCDF conventions (even before it appeared in the netcdfgroup), as I am the netCDF sponsor here at GFDL. That doesn't necessarily make me an expert, but I have been pretty immersed in netCDF for the past couple of years and conventions have been an issue for far longer than that. I must first back up and apologize for taking so long to respond to your extraordinarily thorough effort, which deserves an equally thorough evaluation by the rest of us in the netCDF community. I am just finishing up my N-th pass through it (the information density is quite high!), and I will send you some more detailed comments next week. In the meantime, I at least owe you some overall impressions... 1. Your ideas about "bounds_", "subcell", and "contraction" offer some very valuable ideas about how to handle averages, a subject we have been wrestling with for some time. I still have some questions about just how to apply these, but this could well be the most valuable addition (conceptually) that we will extract from your proposal. 2. A "calendar" attribute is something we adopted early on and is, obviously, a crucial piece of metadata (though there is still some debate about exactly how to use it, "unitime" notwithstanding). 3. I was surprised at the absence of any CDL examples in your document. A few CDL snippets (say, 20-30!) would have helped immensely. 4. In general, I am opposed to the use of external tables. While they can be handy for centers which exchange much the same data all the time, it is problematic for researchers who can sometimes get quite "imaginative" and end up with things that aren't in the "official" table. Complicating things is the fact that there often tends to be more than one "official" table. 5. I heartily agree with your distinction between "missing" and "invalid" values. This is a definite increase in information content that has not been exploited to date. I will reserve any other comments until I finish this one last pass through the proposal. I join the others who thank you for putting out what was, obviously, a lot of work. I am somewhat surprised at the lack of responses to your proposal in the netcdfgroup, though I suppose some people have responded outside the group (or maybe they are still working their way through it, too!). I hope your ideas eventually make it into some kind of updated set of conventions. While I share some of Brian Doty's concern for the proliferation of conventions, I am fairly confident that a workable methodology can be worked out in which a discipline-independent set of core conventions could co-exist with various extensions agreed upon by individual groups. NUWG? Sincerely- John P. Sheldon (jps@gfdl.gov) Geophysical Fluid Dynamics Laboratory/NOAA Princeton University/Forrestal Campus/Rte. 1 P.O. Box 308 Princeton, NJ, USA 08542 (609) 987-5053 office (609) 987-5063 fax -- "Calm down. It's only ones and zeros." --