GTS LDM Surface Synoptic Observations [JOSS] CONTACT: Steve Williams UCAR/JOSS P.O. Box 3000 Boulder CO 80307-3000 email: sfw@ucar.edu phone: 303-497-8987 1.0 General Description The GTS Three-Hourly Synoptic Observation Data is one of several surface data sets collected by the University Corporation for Atmospheric Research/Joint Office for Science Support (UCAR/JOSS). Included in the data set are the global three-hourly synoptic observations. These data are contained in daily files which are in GEMPAK format. The data were acquired via the UNIDATA Local Data Manager (LDM). 2.0 Data and Format Information 2.1 GEMPAK Format GEMPAK, the GEneral Meteorology PAcKage, is a suite of applications programs, libraries, graphic routines, and device drivers for the decoding, analysis, display and diagnosis of geo-referenced and meteorological data. GEMPAK provides a comprehensive set of meteorological parameter calculations for surface, upper-air, gridded, and remotely sensed data. GEMPAK was originally developed by the Severe Storms Laboratory at the Goddard Space Flight Center of NASA starting in the early 1980's. GEMPAK is currently being developed within the National Weather Service (NWS) by the National Centers for Environmental Prediction (NCEP). For information on GEMPAK see: http://www.unidata.ucar.edu/packages/gempak/index.html 3.0 Quality Control Procedures UCAR/JOSS conducted no quality checks on these data. 4.0 File Naming Convention syyyyymmdd.gem sy is the data type (synoptic observations) yyyy is the four digit year mm is the two digit month dd is the two digit day (UTC) 5.0 References None.