000003723 001__ 3723 000003723 005__ 20200129120058.0 000003723 0247_ $$2DOI$$a10.5194/acp-2018-1170 000003723 037__ $$aSCART-2019-0017 000003723 100__ $$aVan Malderen, Roeland 000003723 245__ $$aInterpreting the time variability of world-wide GPS and GOME/SCIAMACHY integrated water vapour retrievals, using reanalyses as auxiliary tools 000003723 260__ $$c2018 000003723 520__ $$aThis study investigates different aspects of the Integrated Water Vapour (IWV) variability at 118 globally distributed Global Positioning System (GPS) sites, using additionally UV/VIS satellite retrievals by GOME, SCIAMACHY and GOME-2 (denoted as GOMESCIA below), and ERA-Interim reanalysis output at these site locations. Apart from some spatial representativeness issues at especially coastal and island sites, those three datasets correlate rather well, the lowest correlation found between GPS and GOMESCIA (0.865 on average). In this paper, we first study the geographical distribution of the frequency distributions of the IWV time series, and subsequently analyse the seasonal IWV cycle and linear trend differences among the three different datasets. Finally, both the seasonal behaviour and the long-term variability are fitted together by means of a stepwise multiple linear regression of the station’s time series, with a selection of regionally dependent candidate explanatory variables. Overall, the variables that are most frequently used and explain the largest fractions of the IWV variability are the surface temperature and precipitation. Also the surface pressure and tropopause pressure (in particular for higher latitude sites) are important contributors to the IWV time variability. All these variables also seem to account for the sign of long-term trend in the IWV time series to a large extent, when considered as explanatory variable. Furthermore, the multiple linear regression linked the IWV variability at some particular regions to teleconnection patterns or climate/oceanic indices like the North Oscillation index for West USA, the El Niňo Southern Oscillation (ENSO) for East Asia, the East Atlantic (associated with the North Atlantic Oscillation, NAO) index for Europe. 000003723 594__ $$aSTCE 000003723 700__ $$aPottiaux, Eric 000003723 700__ $$aStankunavicius, Gintautas 000003723 700__ $$aBeirle, Steffen 000003723 700__ $$aWagner, Thomas 000003723 700__ $$aBrenot, Hugues 000003723 700__ $$aBruyninx, Carine 000003723 773__ $$pAtmospheric Chemistry and Physics Discussion (ACPD)$$y2018 000003723 85642 $$ahttps://www.atmos-chem-phys-discuss.net/acp-2018-1170/ 000003723 8560_ $$feric.pottiaux@observatoire.be 000003723 905__ $$apublished in 000003723 980__ $$aREFERD