Subscribe free to our newsletters via your
. 24/7 Space News .




ICE WORLD
Thawing permafrost may have led to extreme global warming events
by Staff Writers
Sheffield UK (SPX) Apr 05, 2012


File image: thawing permafrost.

Scientists analysing prehistoric global warming say thawing permafrost released massive amounts of carbon stored in frozen soil of Polar Regions exacerbating climate change through increasing global temperatures and ocean acidification.

Although the amounts of carbon involved in the ancient soil-thaw scenarios was likely much greater than today, the implications of this ground-breaking study are that the long-term future of carbon deposits locked into frozen permafrost of Polar Regions are vulnerable to climate warming caused as humans emit the greenhouse gas carbon dioxide by burning fossil fuels for energy generation.

Researchers in centres across America, Italy and the University of Sheffield, analysed a series of sudden, and extreme, global warming events - called hyperthermals - that occurred about 55 million years ago, linked to rising greenhouse gas concentrations and changes in Earth's orbit, which led to a massive release of carbon into the atmosphere, ocean acidification, and a five degrees Celsius rise in global temperature within just a few thousand years.

It was previously thought that the source of carbon was in the ocean, in the form of frozen methane gas in ocean-floor sediments but now the experts believe the carbon released into the atmosphere millions of years ago came from the Polar Regions.

Professor David Beerling, of the University of Sheffield's Department of Animal and Plant Sciences, said: "For the first time, we have linked these past global warming events with a climatically sensitive terrestrial carbon reservoir rather than a marine one. It shows that global warming can be amplified by carbon release from thawing permafrost."

"The research suggests that carbon stored in permafrost stocks today in the Arctic region is vulnerable to warming. Warming causes permafrost thaw and decomposition of organic matter releasing more greenhouse gases back into the atmosphere.

"This feedback loop could accelerate future warming. It means we must arrest carbon dioxide emissions released by the combustion of fossil fuels if humanity wishes to avoid triggering these sorts of feedbacks in our modern world."

The breakthrough was made through cross-disciplinary collaborations with climate and vegetation modellers, isotope geochemists and permafrost experts led by Rob DeConto at the University of Massachusetts, in collaboration with the University of Sheffield, Yale, the University of Colorado, Penn State, and the University of Urbino, Italy.

Rob DeConto added: "Similar dynamics are at play today. Global warming is degrading permafrost in the north Polar Regions, unlocking once-frozen carbon and methane and releasing it into the atmosphere. This will only exacerbate future warming in a positive feedback loop."

The temperature of Earth's atmosphere is a result of energy input from the sun minus what escapes back into space. Carbon dioxide in the atmosphere absorbs and traps heat that would otherwise return to space.

The global warming events were accompanied by a massive input of carbon to the atmosphere plus ocean acidification, and were characterized by a global temperature rise of about five degrees Celsius within a few thousand years.

Until now, scientists have been unable to account for the massive amounts of carbon required to cause such dramatic global warming events and Antarctica, which on today's Earth is covered by kilometres of ice, has not been appreciated as an important player in such global carbon dynamics.

The research is published in the journal Nature.

.


Related Links
University of Sheffield
Beyond the Ice Age






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








ICE WORLD
Thawing permafrost 50 million years ago led to global warming events
Amherst, MA (SPX) Apr 05, 2012
In a new study reported in Nature, climate scientist Rob DeConto of the University of Massachusetts Amherst and colleagues elsewhere propose a simple new mechanism to explain the source of carbon that fed a series of extreme warming events about 55 million years ago, the Paleocene-Eocene Thermal Maximum (PETM), and a sequence of similar, smaller warming events afterward. "The standard hypo ... read more


ICE WORLD
Earth's Other Moons

Flying Formation - Around the Moon at 3,600 MPH

NASA's Grail MoonKam Returns First Student-Selected Lunar Images

Ecliptic "MoonKAM" Systems Begin Operations in Lunar Orbit

ICE WORLD
Mars missions race, India takes lead

12-Mile-High Martian Dust Devil Caught In Act

The sounds of Mars and Venus are revealed for the first time

Dusty, Acidic Glaciers Could Explain Layered Deposits on Mars

ICE WORLD
'Smart City' ambitions for quake-struck Italian town

Boeing Completes Parachute Drop Test of Crew Space Transportation Spacecraft

New Study Calls For Recognition of Private Property Claims in Space

Conservatives' trust in science has fallen dramatically since mid-1970s

ICE WORLD
China's Lunar Docking

Shenzhou-9 may take female astronaut to space

China to launch 100 satellites during 2011-15

Three for Tiangong

ICE WORLD
Busy first days for ATV Edoardo Amaldi

Space Savings for ISS Science Samples

Europe's ATV-3 Space Freighter Adjusts ISS Orbit

Aerojet Propulsion Helps Deliver Astronaut Care Packages

ICE WORLD
Spy satellite-carrying rocket blasts off

Orbital Receives Order for Minotaur I Space Launch Vehicle From USAF

Space Launch System Program Completes Step One of Combined Milestone Reviews

Russian Proton-M Puts Military Satellite into Orbit

ICE WORLD
NASA's Kepler Mission Awarded Mission Extension

A planetary system from the early Universe

Discovery of an 'alien earth' imminent?

Getting to Know the Goldilocks Planet

ICE WORLD
Court revives Viacom copyright suit against YouTube

Google gives glimpse of Internet glasses

Handover of Japan-built Radar to NASA

New understanding of how materials change when rapidly heated




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement