Stories tagged Greenland

Jul
25
2012

43 percent melt: This NASA satellite image from July 8 shows 43 percent of the Greenland ice sheet was melting.
43 percent melt: This NASA satellite image from July 8 shows 43 percent of the Greenland ice sheet was melting.Courtesy NASA
Johnny Carson used to have a standard round of jokes for the summertime on his Tonight Show.

"How hot is it outside today? It's so hot (insert punchline)," was the standard humorous convention he would use.

NASA researchers have a new take on how hot it is this summer, and it's not that funny. Satellite photos taken this month over Greenland show that the massive ice sheet that covers almost all of the Arctic region island was now melting at some degree earlier this month. Like the tried-and-true diet ads in the back of magazines, NASA has before and after satellite images that show the extent of melting that happened.

The top image, complied from three satellite photos taken on July 8, show about 40 percent of the ice sheet's surface was melting. Areas that are pink show where melting is occurring. Areas that are white show non-melting ice and areas that are grey have no ice cover.

97 percent melt: This satellite image from July 12 shows the melt rate surging up to 97 percent.
97 percent melt: This satellite image from July 12 shows the melt rate surging up to 97 percent.Courtesy NASA
The bottom image, taken on July 12, shows a rapid acceleration of melting on the island, with 97 percent of the ice sheet melting. It's a surge in melting rates that scientists figure happens about once every 150 years. This month's data is the highest melting rate that NASA has seen in Greenland since satellite data has been collected for about 30 years.

A rare warm front stalling over Greenland is the cause of the high amount of melting and by the middle of the month, that front had moved on and things were getting back to normal. You can read the NASA press release about this weather event here.

While the brief massive melting is unusual, it's not a huge immediate threat to Greenland's ice sheet, which is some spots is more than two miles thick.

In other recent Greenland ice sheet news, a huge chunk of coastal ice broke off and is now adrift in the Atlantic Ocean earlier this month. Measuring 59 square miles, the ice sheet is twice the size of Manhattan. You can read more about that story here. Two years ago, an iceberg twice as big as this year's broke off from the same location. Experts say it's extremely rare to have two huge icebergs break loose in such a short amount of time.

Jun
17
2009

Ice sheets in Greenland
Ice sheets in GreenlandCourtesy ...Tim
Did you know that glaciers could be up to two miles thick and weigh more than a million tons? Have you ever wondered how snowflakes become ice? And what’s the albedo effect?

The Center for Remote Sensing of Ice Sheets (CReSIS) has the answer to such questions and much, much more. Over the past four years, CReSIS has been developing technologies, conducting field investigations and compiling data to help understand the rapid changes in the polar ice sheets in Antarctica and Greenland. In conducting this research, their vision is to one day understand and predict the role of polar ice sheets in sea level change.

A total of five multi-disciplinary teams work together to conduct research allowing for efficient and well-coordinated progress. I took a closer look at the Satellite Measurements team and the instrumentation they’re using is quite fascinating. The instruments provide high-resolution information on everything from topography to temperature to surface melt. When comparing how these parameters change over time, the team can determine their effects on sea level, identify potential mechanisms controlling that effect, and then create computational models that explain these changes. You can even follow the field experiments that the center is currently conducting at their blog.

On top of all of that, CReSIS is also helping to inspire, educate and train K-12, undergrad and graduate students by encouraging the pursuit of careers in science and engineering as well as offering a variety of research opportunities. My personal favorite is the Ice, Ice, Baby lessons activities. Who cares if its designed for K-8 students! If you’re looking for something to do on a rainy day, I highly recommend making glacier goo. You can learn a lot while making a mess!

Researchers at Penn State have found a new species of bacteria in Greenland. Big whip – as long as it stays away from me, who cares? Well, this organism is ultra-small (I know what you’re thinking – aren’t bacteria pretty, um, small to begin with? Yeah, but these are super-duper small). It has also survived for 120 thousand years trapped without oxygen under two miles of ice. It may help scientists look for life on cold planets and moons elsewhere in our Solar System. (Which I think is a proper noun and therefore should be capitalized, though I may be mistaken.)

An article in Science magazine notes two of Greenland's largest glaciers, which were thought to be shrinking, have recently stabilized and even increased in mass. Previous estimate of rapid melting were based on just a few observations over a short period of time; additional study showed that the melting period was something of an anomaly.