• About
    • Which Energy Mix is this?
  • Climate News Network Archive
  • Contact
Celebrating our 1,000th edition. The climate news you need
No Result
View All Result
The Energy Mix
  • Canada
  • UK & Europe
  • Fossil Fuels
  • Ending Emissions
  • Community Climate Finance
  • Clean Electricity Grid
  • Cities & Communities
SUBSCRIBE
DONATE
  • Canada
  • UK & Europe
  • Fossil Fuels
  • Ending Emissions
  • Community Climate Finance
  • Clean Electricity Grid
  • Cities & Communities
SUBSCRIBE
DONATE
No Result
View All Result
The Energy Mix
No Result
View All Result
  FEATURED
BREAKING: No Public Finance for East Coast LNG Projects, Wilkinson Says July 4, 2022
‘Climate Math Gets Harder’ as Radicalized Supreme Court Upends U.S. Carbon Regulation July 4, 2022
Dire Living Conditions, Climate-Driven Heat Wave Produce Deadliest Human Smuggling Event in U.S. History July 4, 2022
Ex-Fossil Workers Convert Old Oilfields to Solar Farms After ‘Rapid Upskilling’ in Alberta June 29, 2022
London Becomes Biggest City to Sign Fossil Fuel Non-Proliferation Treaty June 29, 2022
Next
Prev
Home Climate News Network

Underworld threat to melting icecap

June 15, 2014
Reading time: 3 minutes
Primary Author: Tim Radford

 

Radar images of Greenland’s glaciers have revealed a spectacular underground landscape of “skyscraper” ice blocks created by a melt-and-freeze cycle that is accelerating the reduction of the icecap LONDON, 16 June − Researchers in the US have identified a new reason for the acceleration in the melting of Greenland’s icecap − the ice underneath, as it melts and then refreezes, appears to speed up glacial flow. The melt-and-freeze-again cycle is not itself new, as a similar process has been diagnosed under the ice cap of Antarctica. Nor is the process itself necessarily connected with global warming. Such things must always have happened. But Robin Bell, a geophysicist at Columbia University’s Lamont Doherty Earth Observatory, reports with colleagues in Nature Geoscience that they used ice-penetrating radar to identify ragged blocks of ice as tall as skyscrapers and as wide as the island of Manhattan at the very bottom of the ice sheet. These structures cover about a tenth of the island and seem to form as melted water below the ice freezes again. They then warp the ice around and above them.

Easier to flow

“We see more of these features where the ice sheet starts to go fast,” Professor Bell said. “We think the refreezing process uplifts, distorts and warms the ice above, making it softer and easier to flow.” Bell and her colleagues looked at the Petermann Glacier in Greenland’s north, which in 2010 pushed a huge chunk of ice into the sea. Observations suggest that the glacier is moving twice as fast as the surrounding ice, and the hypothesis is that the melt-and-freeze-again process is contributing to this acceleration. Researchers have been troubled for a decade or more by the apparent increase in ice loss from Greenland. Were the whole island to melt, sea levels worldwide would rise by more than seven metres, so the concern is practical. Recently, researchers have found that the bedrock beneath many glaciers is actually below sea level, making the glaciers vulnerable from ocean inflow. They have identified a process called “dynamic thinning”, triggered by warmer air temperatures, and they know anyway that natural geothermal heat flow mis likely to melt the base of the ice and lubricate any acceleration. They have measured a fourfold increase since 1997 in summer flow speeds in the island’s Jakobshavn glacier. And they have indicated that the Greenland icecap each summer becomes more vulnerable to melting because the snows themselves are becoming darker, as more dust blows in from areas that are increasingly ice free.

Ice slide

So the discovery of a process that will make the ice slide to the sea more efficiently is not of itself more sinister. The meltwater could come from a number of sources. The friction created by a glacier as it moves must contribute. So could natural heat flow from the bedrock. Surface ice could melt in the summer sun and drain through crevasses to the base. However, what the discovery helps to offer, literally and metaphorically, is a deeper understanding of the processes at work below the ice. What is not clear is whether the melt-and-freeze cycle will influence the rate at which ice is lost in future. Nor does anyone yet know what triggers the cycle. “The conditions under which such switches occur should be investigated, as they directly affect the ability of an ice sheet to slide over its bed,” advises Joseph A. McGregor, of the University of Texas at Austin, writing in the same issue of Nature Geoscience. − Climate News Network



in Climate News Network

The latest climate news and analysis, direct to your inbox

Subscribe

Related Posts

stux / Pixabay
Air & Marine

Big Seven European Airlines Lag on Reducing Sky-High Emissions: Report

June 13, 2022
76
Ars Electronica/flickr
Solar

Unique ‘Smartflower’ Microgrid to Power Saskatchewan High School

June 13, 2022
155
http://midwestenergynews.com/2013/10/24/as-pipeline-concerns-mount-a-renewed-focus-on-the-great-lakes-enbridge-mackinac-line-5/
Pipelines / Rail Transport

Line 5 Closure Brings Negligible Rise in Gas Prices, Enbridge Consultant Finds

June 10, 2022
206

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

I agree to the Terms & Conditions and Privacy Policy.

Trending Stories

angela n./flickr

‘Climate Math Gets Harder’ as Radicalized Supreme Court Upends U.S. Carbon Regulation

July 4, 2022
118
Wikimedia Commons

BREAKING: No Public Finance for East Coast LNG Projects, Wilkinson Says

July 4, 2022
117
U.S. Navy/picryl

Montreal to Host New NATO Climate Centre as Military Analyst Confronts Global ‘Hyperthreat’

July 4, 2022
81
opinion polling gender green recovery climate action

Conservative Women Far More Likely Than Men to Support Green Transition, EcoAnalytics Research Finds

July 4, 2022
80
Maurits90/Wikimedia Commons

San Francisco Commuter Train Derailed by Scorching Track Temperatures, Extreme Heat

July 4, 2022
49
EdmondMeinfelder/flickr

Dire Living Conditions, Climate-Driven Heat Wave Produce Deadliest Human Smuggling Event in U.S. History

July 4, 2022
35

Recent Posts

Adrian Grycuk/Wikimedia Commons

Youth Climate Case Moves to Top Tribunal in European Court

July 4, 2022
34
Seci/wikimedia commons

Saudi Aramco Talks Net-Zero, Plans to Boost Production Through 2035

July 4, 2022
21
Keith Weller/Wikimedia Commons

U.S. Methane Plan Gives Big Ag a Free Pass

July 4, 2022
28
Fadi Hage/wikimedia commons

Indoor Farming Revolution Comes with Significant Carbon Cost

July 4, 2022
37
Mont SUTTON snow terrain

Southern Quebec Towns Scramble for Solutions as Water Sources Dwindle

July 4, 2022
37
Pxhere

Marine Stewardship Figures Prominently in Latest Project Drawdown List

July 4, 2022
24
Next Post

Tesla Puts All Its Patents in Public Domain

The Energy Mix

Copyright 2022 © Smarter Shift Inc. and Energy Mix Productions Inc. All rights reserved.

Navigate Site

  • About
  • Contact
  • Privacy Policy and Copyright
  • Cookie Policy

Follow Us

No Result
View All Result
  • Canada
  • UK & Europe
  • Fossil Fuels
  • Ending Emissions
  • Community Climate Finance
  • Clean Electricity Grid
  • Cities & Communities

Copyright 2022 © Smarter Shift Inc. and Energy Mix Productions Inc. All rights reserved.

Manage Cookie Consent
To provide the best experiences, we use technologies like cookies to store and/or access device information. Consenting to these technologies will allow us to process data such as browsing behaviour or unique IDs on this site. Not consenting or withdrawing consent, may adversely affect certain features and functions.
Functional Always active
The technical storage or access is strictly necessary for the legitimate purpose of enabling the use of a specific service explicitly requested by the subscriber or user, or for the sole purpose of carrying out the transmission of a communication over an electronic communications network.
Preferences
The technical storage or access is necessary for the legitimate purpose of storing preferences that are not requested by the subscriber or user.
Statistics
The technical storage or access that is used exclusively for statistical purposes. The technical storage or access that is used exclusively for anonymous statistical purposes. Without a subpoena, voluntary compliance on the part of your Internet Service Provider, or additional records from a third party, information stored or retrieved for this purpose alone cannot usually be used to identify you.
Marketing
The technical storage or access is required to create user profiles to send advertising, or to track the user on a website or across several websites for similar marketing purposes.
Manage options Manage services Manage vendors Read more about these purposes
View preferences
{title} {title} {title}