Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Model Helps Scientists Home In On Tropical Climate Controls

22.05.2003


It has long been known that tropical climate - by redistributing vast amounts of solar energy through welling hot air and the formation of towering cumulous clouds - influences weather in other parts of the world.

It remains unclear, however, how much the tropics can be affected by higher latitudes.
Now, with the help of a sophisticated computer model, scientists at the University of Wisconsin-Madison have shown that vast atmospheric "bridges" and oceanic "tunnels," created by overturning air and water, link the high latitudes to the tropics and can warm ocean temperature near the equator.


The finding, reported in the May 13 issue of the journal Geophysical Research Letters, has implications for better understanding global and regional climate change, and is the first to identify high-latitude phenomena that significantly influence climate in the equatorial regions of the world.

The prevailing wisdom, according to Zhengyu Liu, lead author of the paper and director of UW-Madison’s Center for Climatic Research, was that climate and weather phenomena at higher latitudes tended to be static, with no far-reaching influence.

"That was the conventional thinking," he says. "But our model shows that these phenomena are equally weighted, that climate and weather at higher latitudes have as much of an influence on the tropics as tropical weather and climate influence the higher latitudes. Both are very important."

The discovery reveals a hidden climate mechanism that may be of critical importance to studies of past and future global and regional climate change, says Liu.

According to the scenario depicted by the modeling experiments conducted by Liu and colleague Haijun Yang, the heat carried via the atmospheric bridges from the tropics to higher latitudes is reduced as a result of warming climate in the higher latitudes. At the same time, warm extratropical water is funneled into the subsurface oceanic tunnels and is carried to the equator where it upwells and warms the tropical ocean.

The study suggests that even a 2-degree Celsius warming of the ocean in regions beyond the tropics can raise ocean surface and subsurface temperatures in the tropics by as much as 1 degree Celsius as less warm air flows out of the tropics and warm, extratropical water is channeled toward the equator by the oceanic tunnels depicted in the study.

"That is a significant change" in temperature, says Liu. "It is fundamentally important."

The new study, says Liu, provides a missing piece of the climate puzzle. It will enable scientists to gain more insight into climate and climate change as an unknown mechanism is revealed and added to the mix of variables that researchers must grasp as they wrestle with the hugely complex problem of understanding and forecasting climate change.

"The magnitude of this influence and the relative contributions of the atmospheric bridge and oceanic tunnel have remained uncertain," Liu says. "But we have found that the extratropics exert a strong control on tropical climate. This is our first estimate of the extratropical influence on the tropics."

The Center for Climatic Research at the University of Wisconsin-Madison is a leading center of research into world climate. It is a part of the UW-Madison Gaylord Nelson Institute for Environmental Studies.

Terry Devitt | University of Wisconsin
Further information:
http://www.news.wisc.edu/releases/view.html?id=8687

More articles from Earth Sciences:

nachricht Large-Mouthed Fish Was Top Predator After Mass Extinction
26.07.2017 | Universität Zürich

nachricht Strength of tectonic plates may explain shape of the Tibetan Plateau, study finds
25.07.2017 | University of Illinois at Urbana-Champaign

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

CCNY physicists master unexplored electron property

26.07.2017 | Physics and Astronomy

Molecular microscopy illuminates molecular motor motion

26.07.2017 | Life Sciences

Large-Mouthed Fish Was Top Predator After Mass Extinction

26.07.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>