Contribution of late spring Eurasian snow cover extent to Canadian winter temperatures

✍ Scribed by Amir Shabbar; Hongxu Zhao

• Publisher: John Wiley and Sons
• Year: 2011
• Tongue: English
• Weight: 476 KB
• Volume: aop
• Category: Article
• ISSN: 0899-8418
• DOI: 10.1002/joc.2426

✦ Synopsis

Abstract

This study examines intercontinental linkages between late spring and early summer Eurasian snow cover extent (SCE~ss~) anomalies and the following winter temperature anomalies over Canada for the 1972–2006 period. The structure of the second interannual mode of Canadian winter temperatures variability captures the SCE~ss~ related modulation. The North Atlantic winter atmospheric circulation changes associated with the SCE~ss~, resembling the negative phase of the North Atlantic Oscillation (NAO), suggest a possible pathway for the SCE~ss~ influences on the Canadian winter temperatures.

Regression and composite analyses show that the SCE~ss~ relate robustly to the Canadian winter climate. Larger‐than‐normal SCE~ss~ is associated with below normal winter temperatures in south‐central Canada and above normal temperatures over northeastern Canada. Predictive skill of Canadian winter temperatures based on a cross‐validated regression model shows that the SCE~ss~ offers the predictive potential over regions of Canada where El Niño‐Southern Oscillation (ENSO) related skill is weak or nonexistent. Analysis of winter extreme minimum temperatures, by a non‐stationary generalized extreme value model, with the SCE~ss~ as a covariate, exhibits statistically significant changes over Canada resembling a pattern similar to that of winter mean temperatures. Wavelet analysis shows significant coherence between the SCE~ss~ and the second mode of winter temperature variability in the 8–12‐year band. Copyright © 2011 Crown in the right of Canada. Published by John Wiley & Sons, Ltd