Nov. 12 (Bloomberg) -- Shanghai, the world’s largest port, may be the Chinese metropolis most at risk from climate change.

China’s most populous city with 20 million residents, along with Dhaka, Calcutta, Manila and Jakarta are more vulnerable to higher seas and stronger storms related to global warming than other Asian cities, the environmental group WWF said today.

Shanghai, whose name contains the Chinese character for “sea,” is located where the Yangtze River empties into the South China Sea. With an average elevation of 4 meters (13 feet), China’s financial center is vulnerable because of its proximity to the tides.

Elevated seas, surging storms and salt water intrusion in 2006 ruined crops, destroyed homes and damaged wetlands near Shanghai, which is the busiest port by cargo tonnage in the world. Such ecosystem destruction accelerates vulnerability to the encroaching sea, the study said.

Sea levels vary from year to year, depending on many factors including weather. In the Yellow Sea east of Shanghai, the waters have fluctuated in the past decade, rising as much as 25 centimeters (10 inches) over their long-term average and declining more than 20 centimeters, according to a report on the University of Colorado’s Web site.

A 30-centimeter increase in ocean levels by 2050 would lead to flooding of about 54,000 square kilometers (20,850 square miles) of the Shanghai region, or more than half its area, the WWF report forecast.

Shanghai, which comprises a deep-sea port and a river port as the Huangpu River enters the Yangtze, was a small town during the Ming and Yuan dynasties but since the early 20th century has surged in size and economic importance.

Dhaka, Jakarta, Manila

While Shanghai and the surrounding area account for a fifth of China’s economy and may have the financial clout to adapt to some of the risks, Dhaka, capital of one of Asia’s poorest nations, Jakarta and Manila have few resources to cope with rising seas, salt water intrusion and cyclones, the report said.

“Asia is the most populous and arguably the most vulnerable continent in the world because of the high risk of climate impacts and the relatively low adaptive capacity,” the report said.

Indonesia has struggled to cope with natural disasters, some unrelated to climate change, including earthquakes and landslides. In the Philippines, storms last month damaged farm output and added to rising inflation.

Half the World

Cities are home to half the world’s population. They consume almost 75 percent of its energy and are responsible for the same amount of carbon-dioxide emissions blamed for global warming. Many of the world’s biggest and wealthiest cities, including New York and Tokyo, are also in coastal regions.

“Climate change is about changes in water,” said Nicholas Stern, a former World Bank chief economist who wrote an influential report on the costs of climate change in 2006. “The biggest impacts will be lack of it or too much of it.”

Construction of coastal defenses and restoring wetlands and mangroves are among the fixes recommended by the report. In Dhaka, the city the WWF said is most at risk, diversification of crops, growing food on floating areas and better water management will help mitigate some of the potential damage.

Some municipalities are already taking steps to reducing their impact on the climate and adapting to possible change. C40, a group of the world’s largest cities with a combined 700 million population, has committed its membership to reaching the Kyoto Protocol’s target of a 5 percent reduction of carbon- dioxide emissions by 2012 from 1990 levels.

Other cities highlighted in the WWF risk report included Hong Kong, Singapore, Kuala Lumpur, Bangkok and Ho Chi Minh.

To contact the reporter on this story: Jeremy van Loon in Berlin at jvanloon@bloomberg.net.

Last Updated: November 12, 2009 05:49 EST