Source: China Daily
Updated: 2004-10-05 10:45

Arrival of a new Ice Age predicted in "The Day After Tomorrow" may no longer be fictitious, say global scientists as they uncover more and more evidence of a changing world environment.

Such information was discovered recently in western China's Qinghai-Tibet Plateau, where age-old glaciers are shrinking at an unprecedentedly fast pace.

A group of 20 scientists from China and the United States drew this conclusion after they jointly conducted a month-long expedition in the Himalayas and the Gangdise mountains in southern Tibet.

China's chief glaciologist Yao Tandong said that in the past 40 years, Asian glaciers in areas at high latitudes centring on the Qinghai-Tibet Plateau have been waning by an average of 7 per cent annually.

And the glacier reserve in that area is decreasing by 52.8 cubic kilometres to 587 cubic kilometres every year, he told the Xinhua News Agency

According to Yao, the number of glaciers in the mountainous region is 46,298, covering a combined area of 59,406 square kilometres and with a total storage of 5,590 cubic kilometres of moisture.

Also head of the Qinghai-Tibet Plateau Research Institute under the Chinese Academy of Sciences (CAS), he said the glacier shrinkage in the plateau regions has become serious in the wake of worsening global warming in the 20th century, especially after the early 1990s.

The glaciers in southeastern Tibet and the regions at low sea levels have borne the brunt.

The Sino-US scientific research team said they observed a number of broken-up ice islands at 7,694 metres above sea level, which used to be connected with glaciers.

Other evidence they found high up in the snow peaks included different types of icebergs, such as hanging glaciers and valley glaciers, and large ice cataracts, which together prove a worrying glacier contraction.

"The full-scale glacier shrinkage in the plateau regions will eventually lead to an ecological catastrophe," Yao said.

Though the phenomenon will bring about a conspicuous increase of river flows in a short period, it will result in a gradual dry-out of the rivers downstream and lead to severe climate changes, he said.

CAS said global warming has set China's major glaciers, which are the main water sources of northwestern China, diminishing year on year, adding about 6 per cent more runoff flows to the rivers in the neighbourhood annually.

The amount of their water is equivalent to the runoff flow of the turbulent Yellow River, China's second longest.

Yao warns if global warming continues at its current pace, most of the plateau glaciers will disappear from Earth by the year 2100.

Ding Yihui, an expert from the China Meteorological Administration (CMA), predicts the world's average winter temperature will rise by 1 to 2 C by 2050 when the glaciers in western China may decrease by 27 per cent.

Energy overuse and excessive discharge of greenhouse gases such as carbon dioxide are both main causes of global warming.

According to CMA Director Qin Dahe, China now discharges the second largest amount of carbon dioxide in the world.

And it may jump to the first place between 2025 and 2030 if no effective controls are taken, he said during a seminar in Lhasa, the Tibet Autonomous Region's capital.

A joint expedition of more than 40 members, encompassing scientific research workers from China, the United States and Japan, have been conducting a 40-month investigative tour to the northern slope of the Himalayas, and to Tanggula and Nyainqentanglha ranges over topics ranging from glaciers, soil survey and atmosphere since late August.

The scientists have been divided into two teams. The southern team is composed of Chinese and American scientific workers.

The northern team comprising Chinese and Japanese scientists focused on atmo-spheric studies and research into soil, energy and water cycles.