A semiempirical error estimation technique for PWV derived from atmospheric radiosonde data
Data sets
Soundings at Güímar http://www.aemet.es
Sounding data at Lindenberg and Ny-Ålesund http://www.dwd.de/EN/research/international_programme/ gruan/home.html
Low-resolution radiosounding data http://weather.uwyo.edu/upperair/sounding.html