Featured Research

from universities, journals, and other organizations

NASA Study Links Wind And Current Changes To Indian Ocean Warming

Date:
December 7, 2004
Source:
NASA/Jet Propulsion Laboratory
Summary:
A NASA study suggests changing winds and currents in the Indian Ocean during the 1990s contributed to the observed warming of the ocean during that period. The findings, published in a recent issue of Geophysical Research Letters, have potential implications for long-term regional climate variability.

Total linear change of east-west wind stress over the 1992-2000 period. The red-yellow colors between 0š and 20šS indicate the weakening easterly trade wind, which causes less southward export of warm surface water.
Credit: Image courtesy of NASA/Jet Propulsion Laboratory

A NASA study suggests changing winds and currents in the Indian Ocean during the 1990s contributed to the observed warming of the ocean during that period. The findings, published in a recent issue of Geophysical Research Letters, have potential implications for long-term regional climate variability.

"Establishing this correlation provides an important missing piece to the global ocean-warming puzzle and provides vital information for regional governments and climate modelers," said Dr. Tong Lee, study author and researcher at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "These findings from satellite data also advance space exploration by increasing understanding of how complex planetary system elements, such as winds and currents, in our home planet interact to drive climate change. Such technologies, which have been demonstrated to be critical in understanding Earth's climate system, may someday prove useful in studying climate systems on other planets."

Lee's findings are based on sea level measurements from NASA's Topex/Poseidon oceanographic satellite, sea-surface temperature data from the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiometer satellite, and wind data from the European Space Agency's European Remote Sensing satellites. Collected between 1992 and 2000, the combined data reveal weakening of southeasterly trade winds over the South Indian Ocean caused a major circulation of this ocean to wane by nearly 70 percent of its average strength.

The atmosphere heats the upper Indian Ocean. The circulation of this ocean counteracts the atmospheric heating by exporting warm surface water and importing colder subsurface water.

The slowdown of this circulation tends to prevent warm surface water from exiting and colder subsurface water from entering the upper Indian Ocean, raising its average temperature. During this period, the average sea-surface temperature of the Indian Ocean increased by approximately 0.25 Celsius (0.45 Fahrenheit).

"This is a very important and intriguing element of climate observations, suggesting convincingly that a major piece of the world ocean has significantly changed its circulation during the last decade," said Professor Jochem Marotzke, director of the Max Planck Institute for Meteorology in Germany. "While it is too early to say whether the underlying cause is natural variability or human-induced global warming, this result poses an interesting challenge to global climate modelers all over the world," he added.

Multi-decadal warming of the Indian Ocean in the past has affected the North Atlantic climate and was blamed for a devastating drought along the southern edge of the Sahara Desert in the 1970s and '80s. Understanding the cause of this warming and predicting its future evolution are major challenges to the climate community, as the ocean's warming is tied into a much larger global cycle of events. This research suggests the Indian Ocean is subject to the same type of long-term ocean-circulation oscillations that drive weather and climate patterns in the Pacific and Atlantic Oceans.

"The waning wind and ocean currents of the Indian Ocean might be a manifestation of decadal and longer climate variability. This could have significant effects on the ocean's ability to absorb atmospheric carbon dioxide and on the region's marine food web," Lee said.

Like vegetation, the ocean is a natural carbon dioxide "sink" that absorbs variable amounts of carbon dioxide from the atmosphere, depending on winds, ocean currents and temperatures. The weakened wind and ocean currents, along with rising ocean temperatures, could hamper the Indian Ocean's ability to absorb carbon dioxide. Ocean phytoplankton, the base of the marine food web, relies on the nourishment brought up by cooler, nutrient-rich subsurface water to survive and reproduce. The slowed cycling of warm and cold water could also bring fewer nutrients from the depths of the ocean to the surface, resulting in a decrease in the region's biological productivity.

To review the full text of Lee's study on the Internet, visit: http://www.agu.org/pubs/current/gl.shtml/

For information about Topex/Poseidon and its follow-on satellites on the Internet, visit: http://sealevel.jpl.nasa.gov/index.html


Story Source:

The above story is based on materials provided by NASA/Jet Propulsion Laboratory. Note: Materials may be edited for content and length.


Cite This Page:

NASA/Jet Propulsion Laboratory. "NASA Study Links Wind And Current Changes To Indian Ocean Warming." ScienceDaily. ScienceDaily, 7 December 2004. <www.sciencedaily.com/releases/2004/12/041203094932.htm>.
NASA/Jet Propulsion Laboratory. (2004, December 7). NASA Study Links Wind And Current Changes To Indian Ocean Warming. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2004/12/041203094932.htm
NASA/Jet Propulsion Laboratory. "NASA Study Links Wind And Current Changes To Indian Ocean Warming." ScienceDaily. www.sciencedaily.com/releases/2004/12/041203094932.htm (accessed August 27, 2014).

Share This




More Earth & Climate News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Waves, Minor Flooding from Hurricane

Big Waves, Minor Flooding from Hurricane

AP (Aug. 27, 2014) — Thundering surf spawned by Hurricane Marie pounded the Southern California coast Wednesday, causing minor flooding in a low-lying beach town. High surf warnings were posted for Los Angeles County south through Orange County. (Aug. 27) Video provided by AP
Powered by NewsLook.com
Calif. Quake Underscores Need for Early Warning

Calif. Quake Underscores Need for Early Warning

AP (Aug. 26, 2014) — Researchers at UC Berkeley are testing a prototype of an earthquake early warning system that California is pursuing years after places like Mexico and Japan already have them up and running. (August 26) Video provided by AP
Powered by NewsLook.com
Hurricane Marie Brings Big Waves to California Coast

Hurricane Marie Brings Big Waves to California Coast

Reuters - US Online Video (Aug. 26, 2014) — Huge waves generated by Hurricane Marie hit the Southern California coast. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Brazil Tries Genetically Modified Mosquitoes to Fight Dengue

Brazil Tries Genetically Modified Mosquitoes to Fight Dengue

AFP (Aug. 25, 2014) — A factory in the industrial state of Sao Paulo produces genetically modified mosquitoes to fight dengue, a deadly tropical disease more prevalent in Brazil than anywhere else in the world. Duration: 00:57 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins