1 Validation of GlobSnow-2 snow water equivalent over 2 Eastern Canada 3 Fanny Larue1,2,3, Alain Royer1,2, Danielle De Sève3, Alexandre Langlois1,2, Alexandre 4 Roy1,2 and Ludovic Brucker4,5 5 1 Centre d’Applications et de Recherches en Télédétection, Université de Sherbrooke, 6 Sherbrooke, Québec, Canada 7 2 Centre for Northern Studies, Québec, Canada 8 3 IREQ Hydro-Québec, Varenne, Québec, Canada 9 4 NASA GSFC, Cryospheric Sciences Laboratory, Greenbelt, MD 20771, USA 10 5 Universities Space Research Association, Goddard Earth Sciences Technology and Research 11 Studies and Investigations, Columbia, MD 21044, USA 12 13 * Correspondance: Fanny Larue, CARTEL, Département de Géomatique Appliquée, 14 Université de Sherbrooke, 2500 Blvd. de l’Université, Sherbrooke, QC J1K 2R1, Canada. 15 E-mail address:
[email protected] 16 17 Abstract: In Québec, Eastern Canada, snowmelt runoff contributes more than 30% of 18 the annual energy reserve for hydroelectricity production, and uncertainties in annual 19 maximum snow water equivalent (SWE) over the region are one of the main 20 constraints for improved hydrological forecasting. Current satellite-based methods for 21 mapping SWE over Québec's main hydropower basins do not meet Hydro-Québec 22 operational requirements for SWE accuracies with less than 15% error. This paper 23 assesses the accuracy of the GlobSnow-2 (GS-2) SWE product, which combines 24 microwave satellite data and in situ measurements, for hydrological applications in 25 Québec. GS-2 SWE values for a 30-year period (1980 to 2009) were compared with 26 space- and time-matched values from a comprehensive dataset of in situ SWE 27 measurements (a total of 38 990 observations in Eastern Canada).