gov.noaa.ngdc.stp.ionosonde:3091User ServicesDOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commerce20120101All the data contributed come from 1957 through 1990. They have been digitized, reformatted, converted to universal time (the software also can display the data in local meridian time), and passed through quality control filters.To provide a useful parameterization of digital Ionospheric soundings1920010120130101UnknownCompletenotPlanned-180.000000180.00000090.000000-90.000000NASA/GCMD Earth Science KeywordsSpace Physics, Ionosphere, Atmosphere, Indices, Communications, Remote SensingRestriction Code: otherRestrictions; Use Limitation: ; Other: Use Constraints: None; Other: Access Constraints: No Constraints; 20130424Justin MabieDOC/NOAA/NESDIS/NGDC > National Geophysical Data Center, NESDIS, NOAA, U.S. Department of Commercemailing and physical 325 Broadway, Mail Code E/GC4 BoulderCO80305-3328(303) 497-6135Justin.Mabie@noaa.govContent Standard for Digital Geospatial Metadata: Extensions for Remote Sensing MetadataFGDC-STD-012-2002