February 04, 2010
The Tibetan Plateau, with an average elevation of over 4000 m asl and an area spread over approximately 2.5 × 106km2, is the highest and most extensive highland in the world and is often called the "Third Pole". The Tibetan Plateau has a great influence on regional and global climate through thermal and mechanical forcing mechanisms.
This is because the Tibetan Plateau has the largest cryosphere outside polar regions and it is the source of all large rivers in Asia. Indeed, in China it is known as the "Asian water tower". We know that the Tibetan Plateau has warmed in recent years, mainly due to greenhouse-gas emissions, but we now present a general study of this region by analysing climate and cryosphere changes in this Asian Highland.
Based on meteorological station data, re-analyses and remote sensing, the Tibetan Plateau has shown significant warming during the last few decades and it will continue to warm in the future. While the warming is predominantly caused by increased greenhouse-gas emissions, changes in cloud amount, snow-albedo feedback, Asian brown clouds and land-use changes also partly contribute.
The cryosphere in the Tibetan Plateau is undergoing rapid change, including glacier retreat, inconsistent snow-cover change, increasing permafrost temperatures and degradation, as well as thickening of the active layer. Hydrological processes caused by glacial retreat have received much attention in recent years but future research should also focus on additional factors affecting climate change in the Tibetan Plateau, such as variations of climate extremes.
The reliability of re-analyses also needs to be confirmed and more detailed comparisons of these analyses with surface observations must be carried out. Other issues include elevation and weekend effects, and identifying spatial variations in temperature change, along with what causes these changes. Such studies are difficult because we lack reliable data above 5000 m asl.
More details are presented in our paper "Review of climate and cryospheric change in the Tibetan Plateau" published in ERL.
About the author
Dr Shichang Kang mainly focuses on glacier and climate change, environmental chemistry of snow/ice and atmosphere, palaeoclimate and environmental variability recovered by ice-core records in the Tibetan Plateau. He has published more than 180 peer-reviewed papers, of which more than 80 have been published in international journals.Back to Archived Reports List
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