Meteorology / Convert to ARL / GDAS Archive

This menu tab is intended to convert existing one-degree latitude-longitude GDAS GRIB data files to ARL format by selecting any file in the GRIB directory. Subsequent file names will be constructed automatically between the starting and ending day at the hour interval set by the radio-button. Day and hour are assumed to be the last four digits of the file name: {base}{DD}{HH}. Time intervals of 12 hours or more should be avoided in transport and dispersion calculations. Only one month of data or less should be processed into one output file. HYSPLIT cannot properly position to the correct starting data record if there is a month transition included within a data file.

Four different grid conversions are available through the menu. "Extract" is identical to option available through the FTP menu, such that the GRIB data are interpolated to a conformal map projection of 100x100 grid points at 100 km resolution at the center of the latitude and longitude selection of the slider bar. The Northern- or Southern Hemisphere options create a 95-km resolution polar stereographic grid centered about the pole. The global options results in no conformal interpolation and just converts the original one-degree latitude-longitude data to the ARL packed format.



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