Featured Research

from universities, journals, and other organizations

Role Of Tropics In Global Climate Change Gains Attention

Date:
September 16, 2003
Source:
University Of California - Santa Barbara
Summary:
The tropics are being recognized as an important element in the dynamic process of global climate change, according to a new study headed by David Lea, professor of geological sciences at the University of California, Santa Barbara.

Santa Barbara, Calif. –– The tropics are being recognized as an important element in the dynamic process of global climate change, according to a new study headed by David Lea, professor of geological sciences at the University of California, Santa Barbara. Lea is first author in an article in the September 5 issue of the journal Science which delves into a tropical record of climate change –– the Cariaco record –– shedding light on the role of the tropics at the end of the last ice age.

Related Articles


The Cariaco Basin, located on the northern Venezuelan shelf in the tropical Atlantic and southeastern Caribbean region, provides a unique look back in time. A core of sediment from the bottom of the ocean, in that area, contains layers of plankton microfossils that serve as a recorder of past climate conditions.

"This site is unique in the tropics because sediments that are deposited within the basin contain undisturbed annual layers that record past climate changes like pages of a book," said Lea. He explained that temperature records were developed from the sediments by determining changes in the magnesium content of the plankton shells, a highly sensitive technique that was developed previously by UCSB researchers.

The importance of the tropics to global climate change is now seen as far more important than a decade ago, said Lea. Scientists are intrigued because the tropics used to be seen as "relatively passive" in global climate models. If the tropics are a cause or a trigger of climate change then their role becomes critical, according to Lea, and even if the tropics are an amplifier of changes that started elsewhere, then it is still scientifically important to understand how they play that role.

The Cariaco record indicates that three large, rapid shifts of five to seven degrees Fahrenheit occurred in the tropics on time scales of a century or less as the earth warmed at the end of the last ice age, between 14,600 and 11,400 years ago. Similar rapid climate shifts are well known from polar ice cores, but they represent a new discovery in the tropics.

"People used to think the tropics were relatively stable," said Lea. "A change of five to seven degrees is a very large difference. For one, it greatly influences how much moisture is held in the air."

The timing of the warming in the Cariaco record indicates that the changes were synchronous within 30 to 90 years with temperature and climate changes recorded in Greenland ice cores.

One of the biggest concerns, according to Lea, is how the temperature changes correspond to rainfall shifts. "The tropical changes might be due to rapid northward and southward shifts in the latitudinal band of rising air and rainfall that lies near the equator," said Lea. "The shifts in the position of this zone are predicted by climate models simulating deglacial conditions, as well as (more speculatively) future global warming scenarios."

The Cariaco data suggests that rainfall belts shifted by at least 300 miles. "The more we understand about how such shifts happened in the past, the better we can predict future shifts," said Lea.

Other researchers contributing to this study are: Dorothy K. Pak of UCSB; Larry C. Peterson of the Rosenstiel School of Marine and Atmospheric Science, University of Miami; and, Konrad A. Hughen of Woods Hole Oceanographic Institution.


Story Source:

The above story is based on materials provided by University Of California - Santa Barbara. Note: Materials may be edited for content and length.


Cite This Page:

University Of California - Santa Barbara. "Role Of Tropics In Global Climate Change Gains Attention." ScienceDaily. ScienceDaily, 16 September 2003. <www.sciencedaily.com/releases/2003/09/030916075425.htm>.
University Of California - Santa Barbara. (2003, September 16). Role Of Tropics In Global Climate Change Gains Attention. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2003/09/030916075425.htm
University Of California - Santa Barbara. "Role Of Tropics In Global Climate Change Gains Attention." ScienceDaily. www.sciencedaily.com/releases/2003/09/030916075425.htm (accessed October 30, 2014).

Share This



More Earth & Climate News

Thursday, October 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

How A Chorus Led Scientists To A New Frog Species

How A Chorus Led Scientists To A New Frog Species

Newsy (Oct. 30, 2014) A frog noticed by a conservationist on New York's Staten Island has been confirmed as a new species after extensive study and genetic testing. Video provided by Newsy
Powered by NewsLook.com
Raw: Hawaii Lava Approaching Village Road

Raw: Hawaii Lava Approaching Village Road

AP (Oct. 30, 2014) The lava flow on the Big Island of Hawaii was 225 yards from Pahoa Village Road on Wednesday night. The lava is slowing down but still approaching the village. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Endangered Carpathian Ponies Are Making a Comeback in Poland

Endangered Carpathian Ponies Are Making a Comeback in Poland

AFP (Oct. 29, 2014) At the foot of the rugged Carpathian mountains near the Polish-Ukrainian border, ranchers and scientists are trying to protect the Carpathian pony, known as the Hucul in Polish. Duration: 02:17 Video provided by AFP
Powered by NewsLook.com
Deadly Mudslide in Sri Lanka Buries Houses

Deadly Mudslide in Sri Lanka Buries Houses

AP (Oct. 29, 2014) A mudslide triggered by monsoon rains buried scores of workers' houses at a tea plantation in central Sri Lanka on Wednesday, killing at least 10 people and leaving more than 250 missing, an official said. (Oct. 29) Video provided by AP
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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