According to Chinese environmental activist Ma Jun, water pollution and shortages are the most pressing environmental issues facing China. In week 7, Harmony and I discussed China’s growing water scarcity and what it may look like in the future. After Harmony presented background on China’s water supply, the science of water, and China’s water management actions, I talked about the effect of climate change in China and two case studies of water mismanagement. At the end I discussed the Three Gorges Dam and its environmental implications.
China, Water, and Climate Change. China is particularly susceptible to climate change for a number of reasons. The country is already prone to floods and droughts and its water resources are unevenly distributed. China also has an incredibly large population with many people living near the coasts, and its demands on agricultural land are greater than ever. On top of this, many parts of China are mismanaging their water resources.
How has China been affected by climate change so far, and what is its outlook for the future? According to a 2010 article in Nature by Piao et al., temperatures in China have risen 2 ºC since 1960. Compared to the global 0.74 ºC rise during the 20th century, this number is quite high. Like much of the world, the number of droughts and floods are expected to increase, and the article shows that flooding has already risen in the past 50 years. This article also presents data that shows rainfall in the north has decreased since 1960. If this trend continues, water shortages in the north will be exacerbated even further.
The effects of climate change coupled with poor water management have already had devastating effects in parts of China, including Yunnan and Xinjiang Provinces. Yunnan is currently experiencing a severe drought, with 60% less rainfall than in average years. The proximate reason for this may be the El Nino-Southern Oscillation, but other causes include deforestation to plant rubber trees, poor water management, and climate change. The Tarim River Basin in Xinjiang Province is also experiencing a severe water shortage due to both glacial retreat and heavy agricultural water use.
In these examples, water mismanagement and climate change combined to create very unstable economic and social situations. Given that China values its stability so highly, will these events shift the way China sees climate change and water use? China’s water is heavily undervalued, and agricultural water waste is widespread. What will it take for China to see climate change as a security issue, and water as valuable as oil?
The Three Gorges Dam. Completed in 2006, the Three Gorges Dam is the world’s largest power generation facility. For decades, engineers had imagined a dam spanning the Yangtze river in this location in order to control downstream flooding. The controversial project relocated 1.2 million people and flooded 13 cities and 1200 villages to make room for the 58,000 km2 reservoir, larger than the land area of Switzerland. While the project helps to mitigate the region’s devastating floods, it also has a long list of environmental consequences. Some of these impacts include increased landslides, greater seismic activity, harm to Yangtze River organisms, and lowering the river’s capacity to flush pollutants.
Is water engineering the best way for China to cope with floods and the imbalance in its water resources? Is this an effective way to cope with increased floods and droughts due to climate change? In the case of Yunnan, their over-reliance on dams contributed to water shortages and drought. The Three Gorges Dam shows China’s confidence in its ability to engineer water, but it must be careful to consider the long-term impacts on its precious water supply.
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