First continuous GPS soundings of temperature structure over Antarctic winter from FORMOSAT‐3/COSMIC constellation

Abstract

The FORMOSAT‐3/COSMIC mission provides unprecedented spatial coverage of daily sounding profiles of the Antarctic atmosphere. Our analysis shows that temperature profiles from these global positioning system (GPS) soundings agree well with the radiosondes over the South Pole and Neumayer stations during the 2006 Southern Hemisphere (SH) winter season. These GPS soundings reveal a vertical domain of low temperature (e.g., T ≤ −78°C at 28‐km altitude) that is not clearly defined by the Antarctic radiosondes. Latitudinal analysis of the GPS soundings shows that regions with T ≤ −78°C occur from about 10‐km to 28‐km altitudes, indicating an 18‐km thick of the cold vertical layer. The extremely cold regions are found at latitudes between 71°S and 87°S and in altitudes between 15 and 25 km, not coinciding with the geographical South Pole. These results demonstrate the potential of the FORMOSAT‐3/COSMIC data for polar studies.