MONITORING LONG TERM VARIABILITY IN THE ATMOSPHERICWATER VAPOUR CONTENT USING GROUND-BASED GPS RECEIVER NETWORKS

• We have processed 14 years of observations acquiredfrom 33 GPS sites in Sweden and Finland. Estimatedlinear trends in the atmospheric Integrated Water Vapour(IWV), using a 10 degree elevation cutoff angle, are in a range from -0.4 to +0.6 kg/m^2/decade with a typical uncertainty of 0.3–0.4 kg/m^2/decade. The data from 13 GPSsites were processed for 8 different elevation cutoff angles from 5 degree to 40 degree. The resulting IWV trends were compared to the trends obtained from the data acquired at seven nearby radiosonde sites. The results show a clear variation in the trend correlation between the two techniques when different elevation cutoff angles are applied to the GPS data analysis. The best agreement is seen for the 25 degree solution resulting in a correlation coefficient of 0.79.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences (hsv//eng)

Nyckelord

atmospheric integrated water vapour

GPS

elevation cutoff angles.

radiosondes

Publikations- och innehållstyp

kon (ämneskategori)

vet (ämneskategori)