Abstract:
The National Centers for Environmental Prediction (NCEP) decodes, on an operational basis, upper air data from the Global Telecommunications System (GTS) and applies some quality controls. See Observational Data Processing at NCEP. This dataset has the data which NCEP puts in their BUFR format. Software which extracts data from the BUFR file, and places it in a basic text file can be found in BUFRdecode_ADPsfc.tar. This is a synoptically sorted dataset. more...
When stations fail to report over the GTS, or there are other data problems, we can not repair the information.
Quality
WARNING: From sometime in Feb 2001 until sometime in Jul 2002, NCEP's GTS decoder generated wind speeds which are about twice as much as they should be. This was due to the false assumption that the speeds came from the GTS in mps when they were actually knots. This applies to all reports except from the U.S., Russia and ... China. See the document 2xwind_final.pdf http://rda.ucar.edu/datasets/ds464.0/docs/2xwind_final.pdf for a detailed description of the problem. Contact Doug Schusterfor more information.
WARNING: From at least Apr 2000 to May 2002, NCEP's GTS decoder generated wind speeds which are about half as much as they should be from SYNOP data at Scandinavian, Irish, Portuguese, and Eastern European stations. This was due to the false assumption that the speeds came from the GTS in knots when they were actually mps. See the document scand_prob.pdf http://rda.ucar.edu/datasets/ds464.0/docs/scand_prob.pdf or a description of the problem. Note: NCEP decodes the precipitation from the GTS only for North America
Access Constraints
Public domain. We may distribute this data, but we do so without providing access software, and with limited or no format documentation.
Cost: The complete dataset is not free. It is only available from the NCAR MSS. Only users with NCAR computing accounts may download it without charge from DSS. For all others, DSS standard pricing applies. See this ordering information. If the user will accept unfiltered copies of whole files delivered by FTP or written to tapes, the user will qualify for a substantially reduced rate, aka "direct copy rate". http://rda.ucar.edu/services/order/index.html
