Technology & Science

Tropics more affected by global warming: study

Organisms in the tropics may be showing more pronounced effects of global warming, despite the larger temperature changes documented at higher latitudes in the north.

Organisms in the tropics may be showing more pronounced effects of global warming, despite the larger temperature changes documented at higher latitudes in the north.

The researchers believe that increases in temperature are raising the metabolic rates of cold-blooded animals such as frogs, stressing their bodies by requiring them to seek more food and oxygen, rather than focusing on reproduction. ((Tim Laman/National Geographic/Associated Press))

While temperatures have increased the most in the northern temperate zone and the Arctic, according to researchers, the impact on organisms in the tropics may be greater than in colder regions.

Scientists at the University of Washington, Wyoming and the Max Planck Institute for Developmental Biology in Germany took almost 500 million temperature readings from over 3,000 locations around the world maintained by the National Oceanic and Atmospheric Administration's National Climatic Data Center. They tracked temperature changes between 1961 and 2009.

These measurements were then correlated with metabolic changes in cold-blooded animals such as frogs, snakes and fish, which do not use their metabolism to regulate their body temperature.

"The expectation was that physiological changes would also be greatest in the north temperate-Arctic region, but when we ran the numbers that expectation was flipped on its head," said lead author Michael Dillon, an assistant professor of zoology and physiology at the University of Wyoming, in a release.

The researchers believe that increases in temperature are raising animals' temperatures and metabolic rates, stressing their bodies by requiring them to seek more food and oxygen, rather than focusing on reproduction. Organisms in the Arctic are more adaptable to temperature fluctuations because of the seasonal changes in temperature, other research has shown.

"I think this argues strongly that we need more studies of the impacts of warming on organisms in the tropics," Dillon said.

The study is published in the Oct. 7 issue of Nature.