1. Connectivity between Eurasian snow extent and Canadian snow mass and river discharge S. J. Déry, J. Sheffield, and E. F. Wood, Princeton

3. Decreasing river discharge in northern Canada, 1964-2003 Source: Déry and Wood (2005), GRL.

4. Teleconnection between the AO and Hudson Bay river discharge Source: Déry and Wood (2004), GRL.

5. Datasets Satellite-based measurements of mean monthly Eurasian snow extent from NOAA, 1973-2003. CMC mean monthly snow mass over North America, 1979-1997 (Brown et al. 2003). Canadian river discharge from HYDAT, 1973-2003 (Déry et al. 2005; Déry and Wood 2005). Global meteorological fields from ERA-40.

6. Methods Study period: 1973-2003. Normalized time series of monthly Eurasian snow extent, annual Canadian maximum snow mass, and monthly river discharge. Focus on Churchill River (Labrador) and Chesterfield Inlet (Nunavut) Basins. Correlations are then performed, with time lags imposed,and are considered statistically-significant when p < 0.05.

7. Monthly Eurasian normalized snow extent anomalies

8. Churchill River normalized annual snow & river discharge anomalies

9. Chesterfield Inlet normalized annual snow & monthly discharge anomalies

10. Correlation coefficient between monthly normalized Eurasian snow extent anomalies and Canadian annual maximum monthly snow mass anomalies the following year, 1980-1997

11. Correlation coefficient between monthly Eurasian snow extent anomalies & Canadian snow mass & river discharge anomalies the next year

12. Correlation coefficient between annual Eurasian snow extent anomalies & discharge anomalies the following year in 64 rivers of northern Canada

13. ERA-40 difference (1980-1989) in winter/spring a) SLP (hPa) and b) 500 hPa geopotential height (dam)

14. Difference (1980-1989) in winter/spring maximum snow mass (kg m -2 ) from Brown et al. (2003)

15. Physical Mechanism for Pan- Arctic Climate Connectivity Soil moisture anomalies in Eurasia (Barnett et al. 1988, 1989) North Atlantic SST anomalies (Saunders et al. 2003) Polar wave flux activity (Gong et al. 2003) Persistence of snow extent anomalies – AO correlates more significantly to annual (not seasonal) Eurasian snow extent anomalies.

16. Autocorrelation of monthly Eurasian normalized snow extent anomalies, 1973-2003

17. Summary Annual maximum snow mass and streamflow in northern Quebec & Labrador is significantly correlated to Eurasian snow extent anomalies Persistence of the Eurasian snow extent anomalies during spring is critical to pan- Arctic connectivity. Thanks to: Land surface hydrology group at Princeton, Marc Stieglitz (Georgia Tech.), Ed McKenna, & Ross Brown (CMC).

18. Trends in Northern Hemisphere snow extent