Comparison of techniques for Integrated Precipitable Water measurement in the polar region

• Main Author: Kruczyk, Michał
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Institute of Geodesy and Cartography 2015
• Subjects: Greenland; Aerosol Robotic Network
• Online Access: https://dx.doi.org/10.34867/gi.2015.2; http://bc.igik.edu.pl/dlibra/docmetadata?id=552

Geoinformation Issues, 2015, Vol. 7, No 1(7), pages 15-27 : Tropospheric delay estimates (tropospheric product) for selected International GNSS Service (IGS) and EUREF Permanent Network (EPN) stations made it possible to asses two areological techniques in the polar region (mainly in Greenland). Integrated Precipitable Water (IPW) – important meteorological parameter is derived from GPS tropospheric solutions by a known procedure for GPS stations. To convert from the wet part of tropospheric delay (ZWD) to IPW, the relation between 2 m temperature and the so-called mean temperature of the atmosphere above was derived using local radiosonde data for nearby GPS stations. Sunphotometer data were provided by AERONET (NASA AErosol RObotic NETwork). IPW comparisons lead to the determination of a systematic difference between the techniques of GPS IPW and sunphotometer data (not present in the case of RAOBs). IPW measured by sunphotometer CIMEL (Cimel Electronique) is several percent smaller than IPW from GPS (both IGS and EPN solution). The bias changes seasonally and is a function of atmospheric temperature. It signals some systematic deficiencies in solar photometry as the IPW retrieval technique. CIMEL IPW shows some temperature dependent bias also in relation to radiosoundings