Climate variability and change in the sanjiangyuan region

Abstract

Described as the “water tower” of Asia, the Sanjiangyuan region contains the headwaters of the Mekong, Yangtze and Yellow rivers. Climate variability and change in this region therefore has fundamental impacts on a range of climate-related ecosystem services. This chapter presents an overview of the climate controls and the characteristics of the Sanjiangyuan region as well as the nature of observed climate variability and change. The climate of the Sanjiangyuan region is the outcome of both regional and distant climate processes. The region lies in a transitional zone between semi-arid and sub-humid climate conditions, the result of geographical and seasonal contrasts in moisture receipt from distant source areas over the Indian and Pacific oceans and the South China Sea. In addition to marked temperature and precipitation seasonality, inter-annual climate variability and extremes are marked features of the region’s climate. Despite the paucity of observational data, it is clear that the Sanjiangyuan region is experiencing pronounced changes in climate, the origins of which are yet to be established unequivocally. The advance of rapid economic development against a backdrop of a highly variable climate resource and an uncertain climate future raises the spectre of ecosystem service degradation and the challenge of managing climate-related ecosystem services. An improved understanding of Sanjiangyuan region climate-forcing factors at the regional to global scale, regional climate characteristics and the possible consequences of human-induced climate change will assist with meeting this challenge, as will building capacity in climate risk management.