Friday 11 October 2013

Melting permafrost

Around The Arctic, Frozen Earth Is Thawing And Creating ‘Drunken Forests’



9 October, 2013

On September 18, just a few days before the IPCC released its 5th assessment report on the state of the warming planet, the Alaskan city of Fairbanks was dusted with the year’s first snow, a full two weeks earlier than expected. Those who claimed that the premature winter wonderland was evidence that the planet is as chilly as ever must have overlooked all the trees in Alaska which tilt an odd angles, the cracked and pothole-ridden roads, and the houses that appear to be sliding downhill on level ground.

Alaska may sometimes look as cold as ever at a glance, but underground, it’s melting, and as it melts, it sinks.

Several feet underneath much of Alaska is a layer of soil known as the permafrost, which as the name implies, is permanently frozen throughout the year — or at least it used to be. Over the last fifty years, Alaska has warmed twice as fast as the lower 48 and ground temperatures have been steadily increasing since the 1970s. Some models predict that by mid-century one-third of Alaska’s permafrost will have thawed and that by 2100, two-thirds will be gone.

While homeowners in parts of Alaska groan over cracked driveways and sinking decks, and the state grimaces at the expense of insulating its roads from the thawing ground, many tribal villages are sinking into the messy business of attempting to relocate.

In Southwest Alaska, the Yup’ik Eskimo village of Newtok has already lost its old school and community center to the sinking ground and despite infighting and considerably complicated logistics, is actively working to move the entire village to a new site on higher ground known as Mertarvik.

Less obvious than sinking villages, are, of course, the massive amounts of carbon dioxide and methane that scientists predict will be released as the world’s permafrost thaws in coming years.

New research released this week has shown that another once icy area, the Hudson Bay lowlands, is also becoming decidedly less frozen.

Writing in the Proceedings of the Royal Society B, researchers from Queen’s University report that this area of rivers, lakes and peat bogs, long considered an ecological refuge of steady temperatures, in the especially climate-sensitive Arctic, has been warming at alarming rates since the 1990s.

Over the last two decades, the Hudson Bay Lowlands have warmed by about three degrees Celsius, which has pushed the once ice-choked bay over a tipping point and on a path toward accelerated warming in the years to come. Sediment core samples from the bottom of lakes in the region show that the animal and plant life that form the foundation of the ecosystem have already changed dramatically, which will cause cascading effects higher up the food chain.


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