It’s very rare for there to be such a storm in the summer. In the past a storm like this would arise in winter and blow snow around on top of a thick ice cover. This summer, over thinner ice, the wind creates large waves which, combined with warm temperatures of air and water, are causing havoc with a keystone of the global climate. The thinner summer ice is breaking up into smaller chunks and melting away rapidly. It is occupying a much smaller area and is getting extremely thin and weak.
The Arctic and especially the sea ice are key to moderating the global climate. Arctic ice physically reflects most of the incoming solar radiation harmlessly back into space, keeping the surface temperatures cold. When water replaces the melting ice it absorbs much more sunlight and thus increasingly heats up the ocean and atmosphere. This extra heat melts even more ice in a vicious heat amplifying feedback cycle. In fact the cyclone mixes the cold fresh surface water from ice melt with much warmer saltier water from under the ocean down to 500 metres deep. Satellite pictures reveal very rapid decline in sea ice over a very short time.
We are now observing climate change in the North occurring decades sooner than all the computer models predicted. The implications of ice loss are enormous. This isn’t about saving polar bears or keeping the north pristine for rich eco-tourists. Massive ice loss and subsequent polar heating five times faster than the global average causes the equator-to-polar temperature difference to plummet, changing the speed (slowing), location, and waviness of the jet stream. This increases the frequency and severity of torrential rains, causing flooding, and of heat waves, causing drought. In a warming world there is more evaporation from water bodies increasing the water vapour content in the atmosphere (four per cent higher over the last 30 years) which condenses into clouds and acts as fuel to intensify storms.
In 2007 more ice melted in the Arctic than in any previous year and this year the rate of melt is even more alarming. Before we had the massive cyclone, based on estimates of sea ice volume there was a greater than 50 per cent chance that the sea ice will vanish by the end of the melt season in 2015. With the unexpected summer cyclones occurring these odds are now much too conservative.
Models predicted the Arctic Ocean could be ice-free in 30 years but the observed changes now indicate it could happen in as little as two years (and no more than seven). Or even by the end of September this year if there are a few more cyclones! Another cyclone was projected for Aug. 24 according to the long range meteorology models.
All bets are off with previous predictions since these numbers did not take into account cyclone activity such as we are seeing this year. We did not anticipate this emerging weather pattern or the amount of damage to sea ice it would cause. World governments have relied on these models and Intergovernmental Panel on Climate Change (IPCC) consensus and taken a go-slow approach to reducing emissions and postpone investing in the infrastructure needed to adapt to the changing climate. The result of accelerated climate change will be far more devastating than the anticipated gradual linear increase in temperature, droughts and storms we have been experiencing over the last few decades.
What we are observing should be understood as our canary in the coal mine giving us warning of more severe conditions ahead. We’re not talking about Las Vegas here—what happens in the Arctic does not stay in the Arctic.
Greenland is also seeing a devastating melt. Last year’s ice-loss just exceeded that in any previously recorded year, and there is still a month left in the melt season! The Greenland melt will, unfortunately, rapidly increase the rate of sea level rise.
Antarctica is also seeing rapidly accelerating ice loss over the last decade—where warming ocean water is melting the ice from below. We have all seen the reports and pictures of large chunks of ice breaking. Pressure cracks are now appearing on the ice shelves of Antarctica where the ice is attached to the shore.
Arctic ice is in a death spiral and the situation is dire.
When the speed of change changes, the speed of response must also change. We know what to do—will we allow our own lethargy and vested interest to stop us from doing it?
Paul Beckwith is a PhD student with the laboratory for paleoclimatology and climatology, department of geography, University of Ottawa. John Bennett is the executive director of Sierra Club Canada.
Original Article
Source: hill times
Author: PAUL BECKWITH, JOHN BENNETT
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