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> Is there a location where CMC data can be found in IDV? I am hoping to > calculate "real-time" Potential Vorticity fields from the GDPS and RDPS > data over the entire domain of each model, but I cannot easily get the data > into IDV as a single grib file from their CMC's Datamart: > http://dd.weather.gc.ca/ > > To get to the GDPS from there, you can navigate here: > http://dd.weather.gc.ca/model_gem_global/25km/grib2/lat_lon/ > > All of the files within those directories are separated by individual > variables rather than collated into one big grib2 file. > > I am assuming that if I get their data files into IDV, I could use the > derived fields to get to Potential Vorticity, but that may be overstepping > the file capabilities. If so, is there a way to calculate Potential > Vorticity from the available variables in CMC's datamart? Here is a list > of all the variables: > http://weather.gc.ca/grib/GLB_HR/GLB_latlonp24xp24_P000_deterministic_e.html > > Hope you have some insight. Thanks. > > Bryan > > -- > Bryan Guarente > Instructional Designer/Meteorologist > The COMET Program > Boulder, CO > > Hi Bryan, I think you need to use the formula for your requirement. Load the data files first for all variables needed for the calculation, and then either call the build in formula or write your own formula. I check we do have potential vorticity based on theta and wind. You do need to learn how to use these formula. You can stop by my office if needed. Yuan Ticket Details =================== Ticket ID: TJT-228211 Department: Support IDV Priority: Normal Status: Closed =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.