The continuous retreat of the cryosphere in China, induced by global warming over the past decades, poses seriously challenge on water security for an entire 2.7 billion people in Asia, warns a CAS scientist.
Prof. QIN Dahe, glaciologist and a CAS Member, made the remarks during the academic conference of the 14th CAS General Assembly held on the morning of 26 June in Beijing.
The cryosphere is the portion of the Earth's surface where water is in solid form, such as glaciers, snow cover, frozen ground, sea ice, lake ice, river ice, ice caps and ice sheets. As an integral part of the world's climate system, it plays a significant role in climate model response to global change, says Prof. Qin in a report entitled Climate change and advancement in cryosphere science on the fourth day of the Assembly.
According to the Fourth Assessment Report of Intergovernmental Panel on Climate Change (IPCC), from the year 1906 to 2005, global warming led to not only an increase of global average temperature by 0.74℃, but large-scale snowmelts and sea level rise. Frozen ground in the Arctic is melting at twice the speed of average global change, and a maximum of 7% seasonal permafrost has gone away ever since 1900.
When global warming is widely recognized as a major issue for sustainable development in the 21st century, cryosphere science becomes a hot and key research subject.
China's cryosphere holds the source of ten major lakes and rivers running across Asia, including the Yangtze River, the Yellow River, the Tarim River and the Salween River, among others. Prof. Qin's investigation shows the impacts of cryosphere changes upon these water sources: contemporarily, melting glaciers may increase the runoff of these rivers; however, with their gradual retreat, it will finally lead to a reduction and even drain of the water bodies. As a result, people affected across China and the rest of Asia can reach as many as 2.7 billion.
A better understanding and control over cryosphere changes hold the key to much more than that, of course. It helps maintain the ecological stability of cold and arid regions of China's west, boost economic development of oases, and ensure a safe operation of domestic climate mechanism as well as that of our neighboring countries, the professor adds.
The glaciologist also offers general suggestions to combat against global change. He urges the setup of an enhanced system for climate observation and monitoring in the country as soon as possible. He also insists on more research and development on climate system models, to reduce risk and get prepared for disasters, and to improve disaster assessment for policy-makers.
Prof. Qin is known as the first Chinese ever to trek through the Antarctic. During 2004 to 2007, he worked with overseas collaborators at IPCC Work Group 1 and was deeply involved in the compilation of the Panel's climate assessment reports, the fourth of which won last year's Nobel Peace Prize. Prof. Qin also served as head of China Meteorological Administration from 2000 to 2007. At present, he works with the State Key Laboratory of Cryosphere Science under the Lanzhou-based CAS Institute of Cold and Arid Regions Environmental and Engineering Research.
Also at the academic conference, Prof. YAO Tandong, Prof. Qin's colleague at the State Key Laboratory of Cryosphere Science and director of the CAS Institute of Tibetan Plateau Research, delivered a speech about High Asia warming, glacier retreat, and water security in northwest China based on ice-core analysis.
China, with a wide distribution of cryosphere, is a country most severely affected by disasters like glacier lake outburst flood/debris flow, ice avalanche, snow avalanche and permafrost thaw. For instance, on the Tibetan Plateau, or along the Qinghai-Tibetan Railway and some oil pipelines and fiber optic networks in the region, cryosphere disasters can lead to huge losses of life and property.