Monday, December 15, 2008

Greenland's Glacier Melt Continues to Accelerate

Researchers watching the loss of ice flowing out from the giant island of Greenland say that the amount of ice lost this summer is nearly three times what was lost one year ago.


The research team has been monitoring satellite images of Greenland to gauge just how much ice flows from landlocked glaciers towards the ocean to form floating ice shelves. Eventually, large pieces of these ice shelves will break off into the sea, speeding up the flow of more glacial ice to add to the shelves.

Warming of the climate around Greenland is believed to have added to the increased flow of ice outward from the mainland via these huge glaciers.

Using daily images from instruments called MODIS (Moderate Resolution Imaging Spectroradiometer) aboard two of NASA's satellites, Box and his team are able to monitor changes in 32 of the largest glaciers along Greenland's coast.

They determined that during the summer of 2006-2007, the floating ice shelves at the seaward end of those glaciers had diminished by 24.29 square miles (62.9 square kilometers. But one year later -- the summer of 2007-2008 – the ice loss had nearly tripled to nearly 71 square miles (183.8 square kilometers). Much of this additional loss is from a single large floating ice tongue called the Petermann glacier

Late this summer, the Ohio State researchers were able to watch as a massive 11-square-mile (29-square kilometer) chunk broke off from the tongue of the massive Petermann Glacier in Northern Greenland. At the time, they also noted that a massive crack further up the ice shelf suggested an even larger piece of ice would soon crack off.

Box said that some findings may have confused the public's views of what is happening around Greenland. "For example, we know that snowfall rates have increased recently in this region," he said, "but that hasn't been enough to compensate for the increased melt rate of the ice that we're seeing now."

I have a global warming post coming. It's a monster and continues to grow. IMNSHO, we're really underestimating the sea level rise from Greenland and Antarctica's melt.


Anonymous said...

From what I understand, the total amount of water both icecaps possess would raise sea level about 60 meters. Are you saying it would be much higher?

Will Baird said...


I've seen several estimates for the amount of water that could be released. The projections that I hear locally are that we'll end up with a 9m rise in the next century.

However, what is 100% possible - as in what is the total of the ice in the world that can be melted - remains to be seen. The estimate I'd heard for a VERY long time was 45m.

However, I've been seeing larger numbers too and there's always the question of why at times in the past why we had the Cretaceous inland seas and whatnot. That there were few to no glaciers is one reason, but there are others as well (probably more uplift on the continents has made the old sea floor rise, ocean basin expansion, etc).

I'm probably going to stick to the 45m number for now, but need more data.

Now, as for what I am saying here is that I am quoting an article that the rate of sea level rise is going to be higher than the IPCC has said. I've always said that.