The Qinghai-Tibet Plateau is growing warmer and experts warn, if the trend continues, it will cause environmental deterioration and water shortages.

"The Qinghai-Tibet Plateau is among the regions worst hit by global warming. In turn, this will have a deleterious effect on global climate and also the livelihood of Asian people," said Qin Dahe, of the Chinese Academy of Sciences (CAS), a former head of the China Meteorological Administration (CMA). He was also the first Chinese person to cross the South Pole.

The temperature in the Tibet Autonomous Region has risen by an average of 0.32 degrees Celsius every 10 years from 1961 to 2008, much higher than China's national warming rates of 0.05 to 0.08 degrees. Tibet's average temperature in July this year was the highest since 1951, according to CMA data.

Rain in western and southern Tibet lessened by between 30 to 80 percent compared to the same period in previous years.

"Due to global warming, glaciers on the Qinghai-Tibet Plateau are retreating extensively at a speed faster than in any other part of the world. In the short term, this will cause lakes to expand and bring floods and mudflows.

"In the long run, glaciers are vital lifelines for Asian rivers such as the Indus and the Ganges. Once they vanish, water supplies in those regions will be in peril," Qin said.

Yao Tandong, one of China's leading glacier experts and director of the Qinghai-Tibet Plateau Research Institute of CAS, echoed Qin's view, saying glaciers on the plateau were accurate archives of past climate change.

"Glaciers on the plateau show warming has been abrupt and exceptional. It is warmer now than at any time during the past 2,000 years," Yao said.

The plateau is world's third largest ice store. So far, about 82 percent of glacier surface on the plateau has retreated and the glacier area itself has decreased by 4.5 percent during the past 20 years.

The Intergovernmental Panel on Climate Change (IPCC), a United Nations body studying global warming, predicted in May that glaciers on the Himalayas (including the Qinghai-Tibet Plateau) could vanish within three decades at present warming rates.

Another huge threat because of warming was the degradation of permafrost, or perennially frozen ground, Qin said.

"Permafrost plays a vital role in protecting the ecological environment and hydrological cycles. But it has been breaking down during the past 50 years. Deterioration will eventually destroy ecological balance, cause land desertification and present a series of tough problems," Qin said.

"If vegetation cover on the plateau decreases, consequent absorption of solar radiation will change the intensity of summer monsoons in Asia," Qin said. "This will bring drought to north India and intensify floods in southern China and droughts in the north."

He said construction works in the permafrost region would also face tough challenges caused by rising temperatures and permafrost degradation.

"The Qinghai-Tibet railway and highway surfaces may possibly become deformed in the future," Qin said.

But Cheng Guodong, a CAS researcher and a member of the Qinghai-Tibet railway project team, was optimistic about construction work.

"After we took measures to cool (to stabilize) the permafrost under the railway, it hasn't melted during the past three years. I believe the railway will be safe over the next 50 years," he said.

Qin said there were positive aspects to the warming.

"Warming is good for agriculture and tourism. It has increased the growing season of crops as well as the tourism season," Qin said.

Scientists agree the Himalayan region is one of the most sensitive and vulnerable to global climate change, and it has shown consistent warming during the past 100 years.

"The region is like an antenna and reacts quickly to global warming," said Andreas Schild, director general of the International Center for Integrated Mountain Development in Nepal, at the 5th International Symposium on the Qinghai-Tibet Plateau in Beijing last week.

"Warming will also evaporate more water into the stratosphere and thus accelerate warming which will influence or even alter global climate," said Schild.

As the world's highest and most complex mountain range, the Himalayas stretch across six countries including China, India and Nepal. Several major rivers in Asia such as the Indus, the Ganges, and the Yangtze, arise there, and their combined drainage basin is home to more than 2.7 billion people, Qin said.

Because of its unique ecosystems and environment, height and vastness, the Himalayan region is often called the "ecological umbrella of the world."

Schild said Asian nations should make more systematic efforts and bolster regional cooperation in studying ways to slow warming as well as measures to adapt to it.

Qin said warming should be taken into consideration while making policies and plans for economic and social development.

"Government plans should be in accordance with the region's climate, resources and environment, and promises of construction sensitive to ecology and environmental protection should be backed up by practical measures," Qin said. Disaster monitoring and warning systems were vital.

Warming has become "a cruel reality that many countries and regions in the world have to face, but it is not a problem that can be handled by one region or country alone", Qin said.

"Warming in the past 50 years has mainly been caused by human activities, especially greenhouse emissions from developed countries. It's global and it needs widespread efforts from international communities," Qin said.

(Xinhua News Agency August 17, 2009)