Weather Whys, March 10, 2013

Winter 6th-warmest on record
It is early March so, at least for some, the winter season is over. This winter featured very mild temperatures for the first half – until mid-January. Temperatures for the first six or seven weeks of winter averaged about 7°C above seasonal. Three extended periods of above 0°C combined with minimal snowfall and resulted in bare ground in mid-winter.

Fortunately, the second stage of winter had a combination of cooler temperatures and several light snowfalls before a few days of very cold nights and days. Only two nights were below -30°C (-33.3°C and 36.3°C) but afternoons around -16°C and often windy conditions made this the coldest week of the winter.

This was a beginning of a see-saw of temperatures that persisted through later January and throughout February. Several snowfalls during the first three weeks of February refreshed trails and slopes and continued the late start to this winter’s outdoor recreation. Bright sunshine for many days, declining snow cover and idle snow ploughs concluded the month of February.

Winter this year was the sixth warmest in the Thunder Bay Airport (1941 to 2013) records. Both December and January were nearly 5°C warmer than normal, February was normal.

However, March has a deserved reputation for weather volatility; the lamb and lion images come to mind. Changeable weather with rapid swings from mild and sunny to winter storm conditions have to be expected.

Another feature of this month is a pronounced freeze-thaw cycle. Snow melts and water seeps into pavement during the day. Freezing conditions take place overnight and expanding ice break up road surfaces. The result – pot hole avoidance if possible, trips for damage and front-end alignment and contests that identify the worst streets.

Still on the subject of ice
Ice formation on Lake Superior was quite limited this year. Ice is present in bays and some shorelines but most of the Lake remained ice free through the winter. New ice formation in March, if it happens at all, is thin and breaks up as winds freshen during the day.

Annual ice cover has declined by 63 per cent on the Great Lakes since the 1970s. The most dramatic decline, 76 per cent, has taken place on Lake Superior. A similar loss of ice is taking place on the Arctic Ocean where ice volume is now one-fifth of that present in 1979.

The rapidity of these changes has startled many people because they exceed predictions of even the most aggressive climate change scenarios 20 years ago.

In the relatively recent past a combination of scientific research, warnings and public pressure has resulted in action by governments and policy makers. Reduction of acid rain, clean air legislation and an international treaty to save the ozone layer are prominent examples.

Fortunately, the world did not allow an unrestrained “business as usual” scenario in these decades. Sterile lakes, even more asthma and other respiratory diseases and an epidemic of skin cancers – one does not want to go there.

Evidence and further warnings about dangerous climate change have not resulted in meaningful policy changes and international cooperation as in the past. The “business as usual” lobby was forced to reform its practices in the past but has prevailed (and influenced) government and corporate decisions about remedies to reduce consequences of climate change.

The Government Accountability Office of the United States has added climate change to its list of “high-risk” threats to the nation’s fiscal health: “Climate change creates significant financial risks for the federal government. The federal government is not well positioned to address the fiscal exposure presented by climate change, and needs a government wide strategic approach with strong leadership to manage related risks.”

The Obama administration in the US began soon after the release of this report to talk tough about emissions and was critical of the Harper government’s inaction. Is it possible that accountants will succeed where scientists and environmentalists have not?