Wednesday, August 22, 2007

More typhoons expected to strike, though season is less intense than past

China Daily: One or more typhoons originating from the northwestern part of the Pacific or South China Sea are likely to hit China before the end of this month, experts are predicting. But even if the predictions prove true, this year's typhoon season is shaping up to be less intense than those in years past.

"However, nothing is certain," said Liu Zhenkun, senior engineer at the typhoon and sea weather forecast centre under the China Meteorological Administration (CMA). This year's typhoon season has been marked by small and shorter than normal storms, he added.

As of yesterday, there had been nine typhoons, 3.5 less than the average for this period of the season. The first typhoon this year hit Guangxi Zhuang Autonomous Region on July 5, about a week later than in previous years. On average, about 28 typhoons hit between June and October every year, Qian Chuanhai, a typhoon forecaster at the China Central Observatory, said.

Qian added that ferries and other ships plying coastal waters, as well as civil affairs and disaster relief departments should be prepared for sudden storms. Normally, the typhoons that hit China originate in the northern and western parts of the Pacific and the South China Sea.

Zhang Peiqun, director of the CMA's climate forecast office, told China Daily that the relative lack of activity in the normal air current above the northwestern Pacific had contributed to the abnormal typhoon activity this year. Normally, warmer, damper air in the area cycles upward, while cooler falls to the surface. "The impact of climate change is reflected in the formation of typhoons," Zhang said.

Research has shown that the water surface temperature in the west Pacific is lower than usual, while that in the east Pacific is higher. "The uneven water temperature has resulted in abnormal atmospheric circulation," the director said. The interaction between the ocean and the atmosphere under such circumstances also decreases the possibility of a cyclone happening. Tropical cyclones cause tropical storms and eventually typhoons if they are strong enough, Zhang said.

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