Staggering amount of ice lost in Greenland!

A study has found that there has been a doubling of annual loss of ice mass in Greenland over the period of 2003 to 2010 compared with what it was throughout the 20th century.

Published in the journal, Nature, a team of researchers led by Kristian K. Kjeldsen of the Natural History Museum of Denmark at the University of Copenhagen says the loss is unbelievable – 9,103 gigatons of ice lost since the year 1900.

This information has been derived from a merger of multiple sources like extensive aerial photography, distinct marks left by retreating glaciers on the landscape, satellite observations, etc.

The paper suggests that the glacier retreat more or less kicked off around 1900, it’s been much accelerated now when major human – caused global warming kicked in.

Although there are variations on the estimates, NASA currently states that Greenland is losing 287 billion tons of ice per year.

Greenland’s major mass loss has been occurring consistently from key regions – the northwest and southeast of the ice sheet. However, of late, there has been an alarming thinning from northeast of the ice sheet which holds back fully 12 percent of all of Greenland’s ice mass.

Ice loss from Greenland today occurs through two key mechanisms – melting on the surface of the ice sheet followed by runoff into the ocean, and large calving events at marine based glaciers, which are followed by more flow of ice outward from behind them. The latter process can be quite dramatic which is capable of triggering huge earthquakes as gigaton-sized icebergs detach, roll in the water, and crash into glaciers behind them.

The new research also suggests that Greenland accounts for much rise in sea level and the estimated ice loss of 9,103 gigatons is enough to submerge the entire U.S. interstate highway system and melting of the entire Greenland ice sheet would lead to roughly 20 feet of sea level rise.

One of the most provoking consequence is that a truly gigantic amount of fresh water from Greenland and Canadian arctic glaciers moved into the North Atlantic Ocean and this could depress the Gulf Stream and alter North Atlantic circulation patterns that control weather.

The key question for the future of Greenland’s ice is how high temperatures will go and how long they will stay there.

Greenland is very complex and it’s very difficult to predict what will happen in the future. This also means our future estimates of sea level rise is unpredictable.

Greenland has already contributed so much fresh water to the oceans, and that now its ice loss is speeding up, is more serious. Keeping the temperature below 2 degrees Celsius (or even better, 1.5 degrees Celsius), if achieved, may just be enough to prevent a scenario in which a total melt occurs over time.

Source – The Washington Post.