Earth Science News  





. Climate Change Could Amplify Drought In East Indian Ocean And Australasia

File photo of drought in Australia.
by Staff Writers
Paris (AFP) Jan 17, 2007
Climate change could worsen the impact of an El Nino-like weather system in the Indian Ocean, bring brutal droughts to parts of Indonesia and Australasia, a study published on Thursday says. The weather system is called the Indian Ocean Dipole (IOD), a recently-discovered phenomenon that strikes the tropical Indian Ocean at various intervals, usually several years apart.

Under it, the surface temperature of the sea drops sharply in the southeastern part of the Indian Ocean, off Indonesia and the northern coast of Australia.

At the same time, the temperature rises in the western part of the Ocean, off the eastern coast of tropical Africa.

The result is very disruptive, bringing droughts to Indonesia and parts of Australia, and heavy rain to semi-arid parts of Africa.

Unlike the Pacific's El Nino effect, which can last a couple of years, the IOD usually eases within months as temperatures even out on both sides of the ocean.

As the IOD was only discovered in 1999, very little is known about how it works, especially the climate mechanisms that cause it to be unleashed.

Researchers in Britain, led by Nerilie Abram of the British Antarctic Survey (BAS) in Cambridge, used records from ancient Indian Ocean coral, whose growth is affected by sea temperatures and rainfall, as an indicator for IOD events stretching back into the distant past.

Looking at such records going back 6,500 years, they found that the big driver for the IOD is the monsoon. Years with severe monsoons triggered an IOD.

The finding is worrying, they say.

Monsoons are also linked to the El Nino. When an El Nino happens, monsoons tend to be weaker -- which thus diminishes the risk of an IOD event.

But man-made global warming is breaking down this link, and the trends are towards stronger monsoons, said Abram.

That, as a result, suggest Dipole events will become more frequent, she said in an interview.

"The monsoon is affected by El Nino but with global warming, that relationship is breaking down and the monsoon is strengthening independently of El Nino," said Abram.

"In Indonesia, droughts are likely to be shifted to the time of year when they normally expect the most rainfall, so the impact of that could be quite severe for the people who are trying to live in that area," she said.

"At the moment, Indian Ocean Dipole events already have a dramatic effect on the climate in this area. They already have droughts and wildfires in Indonesia that are a threat to human health and the environment."

The last Dipole event occurred last year, and its predecessor was in the last 1990s.

"Normally the Dipole events peak in October and November, then after the monsoon winds change direction, then it dissipates and things start to go back to normal again," she explained.

The paper appears in the weekly British science journal, Nature.

Source: Agence France-Presse

Related Links
British Antarctic Survey
Learn about Climate Science at TerraDaily.com

Evangelicals Embrace Climate Change Science To Save The World
Washington (AFP) Jan 17, 2007
Evangelical and scientific leaders have united for the first time to sway Americans to back urgent action to stem greenhouse gas emissions that cause global warming threatening the planet. Repudiating the struggle between neo-creationists and defenders of the theory of evolution, a group of prominent scientists, including Nobel prize winner Eric Chivian and NASA's chief climatologist James Hansen, joined US evangelical leaders on Wenesday to launch this unprecedented joint-initiative.

.
Get Our Free Newsletters Via Email
  



  • Rural America Better Prepared For Disaster Management
  • Many Environments Resilient In The Face Of Hurricanes
  • NGC Tool Designed To Save Lives And Protect Property During Severe Weather
  • Japan And US Working On North Korea Emergency Plan

  • Evangelicals Embrace Climate Change Science To Save The World
  • Climate Change Could Amplify Drought In East Indian Ocean And Australasia
  • Lloyd's Insurance Boss Demands Action On Climate Change
  • Nigerian President Calls For International Action On Climate Change

  • Chairman Reacts to National Academies' Earth Science and Applications Assessment
  • Egypt Plans First Remote Sensing Satellite
  • Japanese Government Initiates Space-Borne Hyperspectral Payload Program
  • US Climate Satellites Imperiled By Low Federal Funding Say EO Scientists

  • Ex-OPEC Chief Says Crude Oil Market Oversupplied
  • New Oil Shale Technology Under Development
  • Earth Biofuels To Acquire Controlling Interest In Ethanol Production Facility
  • Brookhaven Lab Scientists Stabilize Platinum Electrocatalysts For Use In Fuel Cells

  • World's Response To Children With Aids 'Tragically Insufficient'
  • UN Body Says EU Ban On Wild Bird Imports Won't Help Stop Bird Flu
  • AIDS Plan Faces Deadly Deficit
  • Avian Flu Unlikely To Spread Through Water Systems

  • Big Vegetarian Mammals Play Critical Role In Maintaining Healthy Ecosystems
  • Big-Brained Birds Survive Better
  • Scientists Discover New Life Forms In The Arctic Ocean
  • Largest Flower Evolved From Family Of Much Tinier Blooms

  • Lead With A Poisonous Electron Shield
  • Oil Slick Fouls Hundreds Of Birds Off Norway
  • Unlocking Pollutants' Effects
  • Stricken Ship On Collision Course With British Gas Rig

  • 40,000-Year-Old Skull Shows Both Modern Human And Neanderthal Traits
  • Hofmeyr-Skull Supports The "Out of Africa"-Theory
  • No Longevity Benefit With Growth Hormone
  • Earliest Evidence Of Modern Humans In Europe Discovered By International Team

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights 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