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Hello Linda and Robb, In response to your e-mail, here is where we stand: the LDM software was installed on one of our external servers which is frequently used as host for outgoing data. Now we would like to run some tests by sending data to another IDD server, some of your machines for instance. Technicalities In general, we would like to send over the IDD system output from our regional GEM model in grib format. As a starting point, we propose the following subset of the GEM output to be sent to the UNIDATA users. Feel free to feedback your suggestions/comments. Fields (49 in total): - geopotential height at 1000, 850, 700, 500, 400, 250, 150, and 100 hPa - air temperature at the same pressure levels + at the model surface - wind components projected on the x- and y- axies of the grid at the same pressure levels + at the model surface - dew-point temperature at the same pressure levels + at the model surface - sea-level pressure - pressure vertical velocity at 700 hPa - surface pressure - accumulated precipitation - instantaneous rainfall rate - total column cloud cover Grid: A polar-stereographic grid over Canada, the U.S. and the adjacent waters. 135x94 points, horizontal resolution of 60km at 60N. The regional operational model is run twice per day based on 00Z and 12Z data, to produce 48-hour forecast. We would like to send the the 0-48 hour forecasts of the above fields from both runs, at a temporal resolution of 6 hours. This will make for 882 fields/products with a volume of ~ 17Mb per day. This seems reasonable, having in mind that the model output from the NMC and ECMWF models you disseminate accounts for 20,000 products and 75 MB per day. However, you may have restrictions for experimental data. As far as I understood from the documentation, each field is sent as a separate file/product so that the users can select the fields they need. Is this so, or can we group several fields as one product ? Say, all fields for a certain forecast hour ? It seems to me that this will make for less trafic. As for GRIB encoding, we use an in-house encoder which is consistent with the WMO GRIB (edition 1) standards. I will get your GRIB decoder from the UNIDATA site and check whether it works with our GRIB data. Is your GRIB decoder decoding into ASCII or some other internal format ? If so, the decoding test should probably be run at your site, as we may not be familiar with the internal format. As a simple test, I guess I can use the pqinsert/pqsend utilities to send you a few files using the LDM software ? I can use the -f option to specify an EXP feedtype. I will also need the address of the remote server I am to send the data to. I'll appreciate any advice about how to use the LDM, what test we can make and how to finish the set-up. Thanks in advance, Ekaterina ______________________________________________________ Division de l'implementation et services operationnels Centre meteorologique canadien Implementation and Operational Services Division Canadian Meteorological Centre e-mail: address@hidden tel: (514) 421-4646 ______________________________________________________ On Fri, 3 Dec 1999, Linda Miller wrote: > Hi Ekaterina, > > I wondered if you've made any progress with the installation and testing of > the LDM for distribution of the GEM data to U.S. universities. I talked with > Robb Kambic of Unidata and he said that he answered an initial email from you, > but we were unsure if you are having problems with it. Be sure to contact us > if there's anything we can do to assist. > > It would be wonderful to get the data moving to university users. > > Thanks, in advance, for any update you can provide. > > Linda > > Linda Miller - address@hidden > External Liaison, Unidata > University Corporation for Atmospheric Research > P.O. Box 3000 > Boulder, CO 80307-3000 > 303 497-8646 fax: 303-497-8690 > URL: http://www.unidata.ucar.edu/staff/lmiller/un.act.html > >