This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.
Steve: Your method for combining the sfc and ship data worked great. I am now creating hourly analyses of pressure and temperature over North America and adjacent coastal waters. Except for occasional bad ship reports, the analyses look good. For convenience, we view these analyses using GARP and overlay the surface obs over land. It's so nice to be able to zoom anywhere. One thing I noticed in doing this is that the reports from Vegreville, Alberta (WVI) are consistently bad (way off both pressure and temperature). Since I was unable to eliminate the report from my .sf file (even after removing the station from the sf_metar.tbl file), I eliminated it in a preliminary fortran program in the analysis script which I use to filter out missing data. Actually, I am using altimeter setting over land and pmsl over the water where altm is not available. Although the altm values are a little different, I like the analyses better probably because there are more stations that report altm than pmsl. I still use the name pmsl for the combined dataset values (in the test.gem file you suggested). The only irritating problem is that in using garp, I can't always depend on automatically getting a 4-mb contour interval for pmsl. I created a new fdf file called MSLPress_Sfc_mb in which I set pres_cint = 4 hoping that that would set the default contour interval, but the cint I get varies from one use to another. I created a new modellabel called SfcPlot to allow me to view the objective analysis grids with Garp for the modelkey 'sfc'. Thanks again for your help with combining the sfc and ship/buoy data. Thanks again for your help in combining the .sf and .sb data. Bob