Hi everyone,
I refer to Chapter 7 on "Data Representative of Cells", 7.1 "Cell Boundaries".
The specification of those boundaries seems to biased towards polygonal boundaries (in the case of a 2D surface). This covers certainly most of the needs but what happens if the cell is defined as a disc of radius x km (with center at the coordinate value)?
Of course, I can always give 10 to 10,000 vertices that will approximate my disc but it does not sound very neat nor efficient. We would have to somehow move away from listing the 'bounds' and start describing the shape of the cell (disc, ellipse, rectangle, etc...). Note that the concepts of "cell measures" and "cell methods" would still perfectly hold.
One example of such a dataset would be one where at each grid location we report the mean/minimum/maximum temperature/pressure recorded by all stations found in a radius of, say, 30 km around the central point.
Another example is satellite data in swath projection where each record is associated to a Field Of View, which is often approximated as a an ellipse.
Did someone give it a thought already?
Cheers,
Thomas
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Thomas Lavergne
Norwegian Meteorological Institute
P.O.BOX 43, Blindern, N-0313 OSLO, Norway
Phone: (+47) 22963364 Fax: (+47) 22963380
Email: t.lavergne at met.no
OSISAF Sea Ice Portal: http://saf.met.no
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Received on Fri Jan 29 2010 - 04:11:23 GMT
