Northern and Southern Hemispheric Smoothed Gridded Data

Northern and Southern Hemispheric Smoothed Gridded Data is a historical digital data set archived at the National Climatic Data Center (NCDC). NORTHERN HEMISPHERE - A project was established at NCDC (then called National Weather Records Center) by the U.S. Navy to produce grid-point data for the surface and Upper Air of the Northern Hemisphere. Monthly mean pressures, temperatures and dew points were produced in the computers at what is now the Fleet Numerical Meteorology and Oceanography Center at Monterey, California. For the upper air, monthly mean heights, temperatures and dew points were produced. Dew points were produced only through the 500-mb surface. The pressure surfaces are 850, 700, 500, 300, 200, and 100 mb. Grid point values for the mean temperatures and dew point were furnished in the Monterey grid and grid intersections of five degrees of latitude and longitude. The height grid is furnished by every five degrees of latitude and longitude. The files now available in the NCDC archives are those that provide the above information in the five by five grids of latitude and longitude. In a cooperative arrangement the original grid-point data extracted from the work charts were furnished to National Center for Atmospheric Research (NCAR) in Boulder, Colorado (NCAR). These data have been screened and continuity checks in time and space made as a feedback to the NCDC for control purposes. The original charts have been modified and new grid-point data have been provided to NCAR. These data have been incorporated where possible. These will be supplemented by another similar package for the Southern Hemisphere. SOUTHERN HEMISPHERE - The basic analyses and selected derived products have been published in four volumes of an atlas covering selected climatic conditions in the southern hemisphere. Volume I (Taljaard, et al., 1969) gives mean monthly isopleth charts of sea- level pressure and of height, temperature and dew point at selected upper levels together with smoothed grid-point values produced by computer analysis from these charts. Volume II will deal with with geostrophic zonal and meridional wind components. Volume III (Van Loon, et al., 1971) with isogons and isotachs of the geostrophic wind. Volume IV (Crutcher, et al., 1971) with selected meridional cross sections of temperature, dew point, and isobaric height.