Ice Sheet on EARTH Magazine

Ice (Re)Cap: March 2018

Tue, 27 Feb 2018 13:27:15 -0500

A new map shows the geothermal heat flux beneath Antarctica in detail. Credit: Martos et al., Geophysical Research Letters, November 2017.

From Antarctica to the Arctic; from polar caps, permafrost and glaciers to ocean-rafted sea ice; and from burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

Greenland's growing deltas: Combining historical and modern imagery to decode change in a telltale Arctic landscape

Fri, 09 Feb 2018 14:50:54 -0500

The coast of Greenland has more than 100 pristine deltas formed by rivers draining from the Greenland Ice Sheet into the sea, interspersed amid the coast's irregular geometry of fjords and icy bays. Credit: Anders Anker Bjørk.

Enormous quantities of fine sediment, sand and rock are carried downstream by rivers flowing off the Greenland Ice Sheet. Where these rivers meet the ocean, they deposit the sandy, coarse part of their sediment loads, forming textbook fan-shaped deltas. Credit: Nicolaj Krog Larsen.

Greenland’s rivers are impressive, with fast, powerful flows of turbulent, milky waters descending from glaciers of the Greenland Ice Sheet, which loom only a few kilometers upstream. Enormous quantities of fine sediment known as “glacier flour,” as well as sand and rock are discharged into and carried downstream by these rivers. The grinding action of the sediment-laden torrents is formidable and carves beautiful smooth sculptures in the solid granite bedrock. From the riverbank, the noise is overwhelming as the loud crashing of the turbulent water flow combines with a rumbling undertone from rocks colliding with the river bottom.

Ice (Re)Cap: October 2016

Wed, 21 Sep 2016 08:18:53 -0400

At glaciers and snowfields around the Arctic, researchers sampled snow tinted by red algae, which bloom in spring and summer and contribute to lowering surface albedo. Credit: Liane G. Benning, GFZ.

Ice (Re)Cap: April 2016

Wed, 13 Apr 2016 17:09:04 -0400

Thawing permafrost in Alaska, which can lead to slope failures like this one along the Noatak River, may increase dramatically this century as air and ground temperatures rise. Credit: Rory Nichols.

Ice (Re)Cap: December 2015

Thu, 12 Nov 2015 10:14:30 -0500

A comprehensive survey of the Greenland Ice Sheet using two decades of ice-penetrating radar data has yielded a three-dimensional view of the internal structure and age of the ice sheet's layers. Credit: NASA's Scientific Visualization Studio.

Ice sheet has had lasting effect on European earthquakes

Fri, 23 Oct 2015 11:47:03 -0400

“Modern Germany is not known for its earthquakes,” says Christian Brandes, a geoscientist at the University of Hannover in Germany. The country, after all, is in the middle of a tectonic plate, he says, away from any plate boundaries or other features that would cause tectonic strain to build up in underground faults.

Ice (Re)Cap: October 2015

Mon, 21 Sep 2015 12:15:05 -0400

The hydro-fracture scarp and exposed lake bed of Greenland's North Lake following a rapid drainage event in 2011 are seen here. Credit: Ian Joughin.

Ice (Re) Cap: June 2015

Mon, 01 Jun 2015 10:18:21 -0400

Researchers deploy a hydrophone in Icy Bay, Alaska, to monitor noise levels in the glacial fjord. Credit: Jeffrey Nystuen.

Down to Earth With: Glaciologist Richard Alley

Tue, 13 Jan 2015 13:05:38 -0500

If you don’t know who Richard Alley is, stop reading for a minute and search for him on YouTube. Go on, this can wait. Back? What you likely saw was Alley singing his rendition of Johnny Cash’s “Ring of Fire,” in which he explains subduction zones, or another similar song. In addition to being something of an Internet sensation for his energetic lectures and songs about geologic processes, Alley is a glaciologist who studies the effects of climate change. Alley’s work has taken him to glaciers around the world, from Greenland to the Antarctic ice sheet. He is also trying to understand how best to communicate scientific ideas to the public. So far those efforts have included singing to his undergraduate classes and filming a television series for PBS called “Earth: The Operators’ Manual.” (There’s a public-friendly book and website of the same title as well.)

Icebergs were the original Florida snowbirds

Mon, 05 Jan 2015 10:14:53 -0500

As icebergs drifted south along the coast, their keels plowed across the seafloor, creating the characteristic grooves shown here in a seafloor bathymetry image from offshore of South Carolina. Credit: Jenna C. Hill.

A new study shows that between 20,000 and 10,000 years ago, icebergs drifted southward off the coasts of South Carolina and Florida.

Ice (Re) Cap: December 2014

Tue, 04 Nov 2014 12:06:57 -0500

University of Copenhagen researcher Bo Vinther, part of a team that assembled a new climate reconstruction for Greenland based on nitrogen isotopes, prepares an ice core for inspection. Credit: Christian Morel.

Ice (Re) Cap: October 2014

Wed, 03 Sep 2014 09:12:25 -0400

Arctic permafrost, or thermokarst, lakes like these release methane, but new research suggests that on millennial timescales, they act as net carbon sinks as decaying organic matter is buried in lake sediments. Credit: UAF/Katey Walter Anthony.

From Antarctica to the Arctic; polar caps, permafrost and glaciers to ocean-rafted sea ice; and burly bears to cold-loving microbes, fascinating science is found in every nook and crevasse of Earth’s cryosphere, and new findings are announced often. Here are a few of the latest updates.

Seeing beneath Greenland's ice

Tue, 02 Sep 2014 13:07:43 -0400

Save the handful of Vikings who settled an ice-free stretch of Greenland’s southwest coast during the Medieval Warm Period a millennia ago, few humans have ever laid eyes on even a fraction of the land that lies below Greenland’s 1.7-million-square-kilometer ice sheet. Now, courtesy of a new model, scientists are seeing a detailed view of the topography underlying the ice sheet, which is an important control on the flow and discharge of ice into the ocean.