. Earth Science News .
Climate change: Atlantic shift has global impact

The new study provides the first concrete evidence of an immediate "seesaw" connection between the North and South Atlantic, say the authors, led by Stephen Barker of Cardiff University in Wales.
by Staff Writers
Paris (AFP) Feb 25, 2009
Big changes in the circulation of the Atlantic Ocean probably have an impact around the globe, according to a study published Wednesday that touches on a key aspect of climate change.

Scientists delved into dramatic swings in climate that are believed to have occurred during the last Ice Age, about 110,000 to 10,000 years ago.

Until now, the evidence for these swings has come only from the northern hemisphere, leaving a knowledge gap about what happened to the climate in the southern part of the globe.

The paper, appearing in the British-based journal Nature, supplies at least part of the answer: when temperatures plunged in the North Atlantic, they soared in the South Atlantic, and vice-versa.

The evidence, culled from a sediment core drilled from the seafloor in the South Atlantic, supports a theory known as the "bipolar seesaw".

Under this hypothesis, when circulation in the Atlantic is badly disrupted, there is a major knock-on, but opposite, effect in the two hemispheres.

In the Atlantic, the Gulf Stream ferries warm water at the surface from the tropics to the northeast.

Thanks to this, Western Europe has a relatively balmy climate, even though it is in the same latitude as the northeastern United States and Labrador, where winters are harsh.

The warm water cools as it heads north, which causes it to sink. The cold returns southward again by deep ocean currents, back to the tropics, where it warms again and so-on.

The new study provides the first concrete evidence of an immediate "seesaw" connection between the North and South Atlantic, say the authors, led by Stephen Barker of Cardiff University in Wales.

What caused the swings during the last glacial age are not known for sure. They were probably fuelled by natural shifts in Earth's orbit and axis, which can have big consequences in the amount of heat we get from the Sun.

But comprehending the seesaw mechanism also has a bearing on understanding climate change today, which is inflicted by manmade greenhouse-gases, the authors say.

One theory is that a spurt of global warming could swiftly melt Arctic ice, causing a rush of cold water into the North Atlantic that would slow the Gulf Stream "conveyor belt" and plunge Western Europe into a deep chill, even a mini Ice Age.

The evidence for this is sketchy or debatable, but the scenario is taken seriously by many climate scientists.

One of the study's co-authors, Ian Hall, a scientist at Cardiff University, said a big shift of Atlantic circulation is unlikely to occur in any near future.

Even so, "our results suggest that if such an extreme scenario did occur, its effects could be felt globally within years to decades."

Share This Article With Planet Earth
del.icio.usdel.icio.us DiggDigg RedditReddit
YahooMyWebYahooMyWeb GoogleGoogle FacebookFacebook



Related Links
Climate Science News - Modeling, Mitigation Adaptation



Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News


Obama calls for carbon cap legislation
Washington (AFP) Feb 24, 2009
President Barack Obama on Tuesday urged Congress to draft legislation setting market-based caps on the emissions of carbon gases in a landmark move in the United States to combat global warming.







  • Floods, landslides kill six in Indonesia: officials
  • Indonesian mud victims to receive compensation: company
  • Midnight Oil reunite for wildfires relief concert
  • One killed in Romanian military lab explosion

  • Obama calls for carbon cap legislation
  • Climate change: Atlantic shift has global impact
  • Analysis: Emission monitoring puzzles reps
  • Climate change risk underestimated: study

  • Orbital's Launch Of Taurus Rocket Is Unsuccessful
  • Counting Carbon
  • Google shoots down 'Atlantis' pictures
  • Five Things About The Orbiting Carbon Observatory

  • Threat of oil spill menaces Russian Pacific island
  • Electricity Systems Can Cope With Large-Scale Wind Power
  • Revolutionary Method Generates New Template For Microelectronics
  • Secrets Behind High Temperature Superconductors Revealed

  • NASA Study Predicted Outbreak Of Deadly Virus
  • McMaster Researchers Discover New Mode Of How Diseases Evolve
  • Climate Change May Alter Malaria Patterns
  • Hong Kong bird tests positive for H5N1

  • Urban elephants ply Bangkok streets in search of tourist dollars
  • Great Lake's Sinkholes Host Exotic Ecosystems
  • Bizarre Bird Behavior Predicted By Game Theory
  • Ribosome Building Blocks

  • Supreme Court mulls who pays after toxic spills
  • China's environment problems serious: minister
  • Arsenic And Old Toenails
  • Dozens hit by food poisoning in NE China: state media

  • Emotions May Be More Reliable When Making Choices
  • Internet Emerges As Social Research Tool
  • Walker's World: The dangerous border
  • Appalachian History Gives New Perspective of How Workers View Jobs

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2007 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. 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 SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement