A series on the projected impact of climate change on China.

Although China spent the last couple weeks rallying the non-Western world against the U.S. at the Copenhagen Climate Conference (and perhaps rightfully so), they shouldn’t be celebrating the deadlock and failure that was ultimately the result.

In the coming decades, the global processes resulting from anthropogenic climate change will unleash an unprecedented ripple effect of change across The People’s Republic of China. The impacts of climate change will flow, with varying magnitude, from the vast Himalayan Mountains to the streets of Beijing, and from the mouth of the Yangtze River to the Tibetan Plateau. Early estimates send a foreboding message: China will be one of the hardest-hit countries in the world if climate changes as scientific consensus currently predicts. This is true not only because of China’s geography, but also because of its sensitive population and development situation. Despite its dynamic economic growth in the recent decades, roughly 140 million people in China are still living in abject poverty. For them the natural environment is the apparatus of their livelihood. Given this delicate situation, lets first look at how climate change will impact China’s water supply:

As the most populous nation in what is already the driest region in the world (per capita), China could experience a very severe, long-term water crisis within the current century due to the noxious combination of continued population growth and climate change-induced drying. As the director of the Asia Society’s Social Issues program, Suzanne DiMaggio, recently conveyed, “The emerging picture on water is very worrisome.” Due to warming temperatures, the Himalayan glaciers, which help supply over a quarter billion people in China with fresh water, are rapidly receding. If current trends persist, it is very likely that these glaciers – the largest outside of the polar regions – will be completely gone by 2035. The result will be particularly harmful for Southern China (and other heavily populated Southern Asian countries): The Red River’s annual flow is predicted to decline by 13 to 19 percent by the end of the 21^st century and, similarly, the Mekong River’s annual flow will be 16 to 24 percent lower than present day levels. As a result, increased water stress is likely to be experienced in China on an unprecedented scale.

Evidence suggests that northern China is already undergoing such water stress. Based on data and the judgments of local farmers in the region, 70 percent of the villages there are experiencing growing water shortages and 16 percent of farmers have faced a reduction in their agricultural production as a result. These shortages are also believed to be catalyzed by both increasing pressure on land and water resources due to climbing populations and to warming temperatures. Run-off in many of northern China’s river basins has alreadybegan a precipitous decline. In one severe example, the Hai River Basin has experienced a run-off decline of 41 percent. The Tibetan plateau and northwestern China mountain glaciers which help supply these river basins, like the Himalayan glaciers, have liquefied by 21 percent over the past five decades. With temperatures in the Tibet region projected to rise afull 3° to 6°C by the end of the century, this glacial melting will only accelerate; further exacerbating water stresses and increasing the incidence of drought.

Compounding the problem, without access to surface water, farmers and local villages are turning to ground water  – a phenomenon that poses its own unique set of environmental challenges and which promises to only become more wide-spread. While in one-third to one-half of the villages being forced to use groundwater the water table has not fallen in amounts large enough to raise concern, in at least half of northern China the water table is showing a measurable fall. More severely, in 10 percent of the villages the water table is falling faster than 1.5 meters per year. Water table decline can cause a number of alarming impacts such as land subsidence, desertification, and seawater ingress into vital freshwater aquifers.

I’ll be discussing agriculture next, so stay tuned!

- Matt