By Joshua S Hill
According to almost 50 years of data, the Devon Island ice cap in the Canadian High Arctic is thinning and shrinking.
A paper published in the March edition of Arctic, the journal of the University of Calgary's Arctic Institute of North America, reports the substantial loss of mass, ice volume and area each year since 1961 of the Devon Island ice cap.
The report shows that between 1961 and 1985 the ice cap both grew and shrank, signifying an overall loss of mass. However, from 1985 onwards, scientists began to notice a steady decline in the volume and area of ice covering one of the largest ice masses in the Canadian High Arctic, an ice mass of approximately 14,400 square kilometres.
This slow death has been evidenced in other ice caps and large sheets of ice the world over. What begins as a couple of years with warmer summers starts a domino effect that is almost irreversible.
The Canadian High Arctic, like Antarctica and the Arctic, is essentially a desert. It might confound the generally held view that to have a desert means either a lot of ice-cream and another s, or a lot of sand and hot temperatures. However a desert is really only an area that receives hardly any precipitation.
As a result, any loss of ice takes a long time to reacquire. An area like the Devon Island ice cap cannot simply rely on a wet winter or lots of snow falling, as there is precious little that falls. Subsequently, one abnormally warm summer can wipe out something like five years of growth.
With a loss like this, the ice becomes thinner and younger. Younger ice is not as resilient to the temperatures, and melts quicker. (Stronger, older ice is able to reflect the heat in a process known as the albedo effect.) Melting ice means the sun has a better chance of getting through to the gravel and dirt below, which suck up heat and store it. At such a point, the ice is melting from the outside and the inside.
Naturally, the first concern to rise to many minds is the possible increase in water levels. But there are more than environmental concerns if you're one of the many apathetic humans around.
"There are a lot of things we need to consider. One is the iceberg calving and its implications for shipping. These things don't just go away, they float out into the ocean," says Sarah Boon, lead author on the paper and a Geography Professor at the University of Lethbridge.
Another effect of the melting is that the melt water runs through to the bottom of the glacier, lubricating the ground on which the glacier rests and increases the speed with which it slides towards the ocean. This creates more and more icebergs, which, as Boon says, aren't going away anytime soon and create a real threat for shipping in the area.
Long term studies like this one are pure gold, as they provide comprehensive data that help us understand the relationship between the ice caps, atmosphere and the oceans. But, as Boon says, "We all know long-term studies are important but they are really hard to pay for."