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Autumn and Winter Storms of the Eastern Canadian Arctic
Reference
Gascon, G., Stewart, R.E. and Henson, W. 2010. Major cold-season precipitation events at Iqaluit, Nunavut. Arctic 63: 327-337.

Background
The authors write that "autumn and winter storms in the eastern Canadian Arctic are typically characterized by heavy precipitation and strong winds [that] can have major effects on the human population and infrastructures, as well as paralyzing transport," noting that the local Inuit "have reported higher occurrences of hazardous weather and unanticipated changes, which increase northern communities' vulnerability and limit their capacity to adapt to environmental change." But is this really the case?

What was done
In a study that speaks to the answer to this question, and which they describe as "the first to document the climatology of major cold-season precipitation events that affect southern Baffin Island," Gascon et al. examined the characteristics and climatology of the 1955-2006 major cold-season precipitation events that occurred at Iqaluit -- the capital of Nunavut, located on the southeastern part of Baffin Island in the northwestern end of Frobisher Bay -- based on analyses of hourly surface meteorological data obtained from the public archives of Environment Canada. The precipitation data from this period were corrected to account for gauge catchment errors due to wind effects, snow-water equivalence variations, and human error in the manually-retrieved precipitation data for the period 1955-1996, while the remainder of the data were used in their uncorrected state.

What was learned
The three researchers report that they detected a non-significant decrease in autumn and winter storm activity over the period of their study, which they say is in line with the results of Curtis et al. (1998), who observed a concomitant decrease in annual precipitation in the western Arctic. And this was the case in spite of the findings of Zhang et al. (2004), who the Canadian scientists say "reported an increase in cyclonic activity over the past fifty years, as well as McCabe et al. (2001), Wang et al. (2004) and Yin (2005)," who reported a northward shift in such activity, but which was apparently not great enough to "translate into major precipitation events, or at least not in Iqaluit," as revealed by the authors' results depicted in the figure below.


Cold-season occurrences of major precipitation events at Iqaluit, Nunavut, Canada. Adapted from Gascon et al. (2010).

What it means
The results of this data-based analysis would appear to raise questions about the validity of the collective memory of the local Inuit, who have reported higher recent occurrences of hazardous autumn and winter weather in this part of the world.

References
Curtis, J., Wendler, G., Stone, R. and Dutton, E. 1998. Precipitation decrease in the western Arctic, with special emphasis on Barrow and Barter Island, Alaska. International Journal of Climatology 18: 1687-1707.

McCabe, G.J., Clark, M.P. and Serreze, M.C. 2001. Trends in Northern Hemisphere surface cyclone frequency and intensity. Journal of Climate 14: 2763-2768.

Wang, X.L., Swail, V.R. and Zwiers, F.W. 2004. Changes in extratropical storm tracks and cyclone activity as derived from two global reanalyses and the Canadian CGCM2 projections of future climate. Eighth International Workshop on Wave Hindcasting and Forecasting, 14-19 November 2004, Oahu, Hawaii. Environment Canada, Paper B1.

Yin, J.H. 2005. A consistent poleward shift of the storm tracks in simulations of 21st century climate. Geophysical Research Letters 32: 10.1029/2005GL023684.

Zhang, X., Walsh, J.E., Zhang, J., Bhatt, U.S. and Ikeda, M. 2004. Climatology and interannual variability of Arctic cyclone activity: 1948-2002. Journal of Climate 17: 2300-2317.

Reviewed 5 January 2011