Jim-- Section 7.4 covers climatologies. My understanding of it is:
1) Those are the right bounds values, but you should reference them using a "climatology" attribute instead of a "bounds" attribute. I would think the cell_methods string for a daily climatology ought to be "time: mean within days time: mean over years", but that doesn't follow one of the three allowed forms for climatologies. I guess the way to make it fit the schema is to use "point" to indicate a no-op for how you're aggregating days within the annual cycle, which gives you: "time: mean within days time: point over days time: mean over years" 2) Quite a conundrum, isn't it? Probably why we don't see more daily climatologies... My inclination would be to simply discard the leap days and use a noleap calendar for your climatology. (Another approach is to normalize time by multiplying it by 360/yearlength, so that you're basically working with orbital position instead of days since some starting point. I find that useful for comparisons across different calendars, but it's a bit unorthodox, and would likely be confusing in a published data product.) In any case, I don't think there's really a standard "best" answer, so the most important thing is to document your choice thoroughly. As long as the end-user can easily figure out how you handled leap days, I think it's reasonable for you to deal with the issue in whatever way you find most convenient. Cheers, --Seth ---- Seth McGinnis [email protected] NARCCAP Data Manager RISC / IMAGe / NCAR ---- On 6/2/14 8:20 AM, Jim Biard wrote: > Hi. > > We have a dataset that contains a climatology giving the daily average > temperature over 30 years. (So, it has the average temperature for > January 1 over the period from 1981 - 2010.) I have two questions about > this. > > 1) How exactly should that be represented, both with the bounds and with > the cell_methods? Should the bounds be (for example) 00:00:00, Jan 1, > 1981 and 00:00:00 Jan 2, 2010? Should the cell_methods be "time: mean > over days time: mean over years"? > > 2) How should we handle February 29? > > Grace and peace, > > Jim > > -- > CICS-NC <http://www.cicsnc.org/> Visit us on > Facebook <http://www.facebook.com/cicsnc> *Jim Biard* > *Research Scholar* > Cooperative Institute for Climate and Satellites NC <http://cicsnc.org/> > North Carolina State University <http://ncsu.edu/> > NOAA's National Climatic Data Center <http://ncdc.noaa.gov/> > 151 Patton Ave, Asheville, NC 28801 > e: [email protected] > o: +1 828 271 4900 > > > > > > > _______________________________________________ > CF-metadata mailing list > [email protected] > http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata > _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
