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Climate change is pushing up the sea level globally. While in Shanghai, such rise is roughly the length of a rice grain in each of recent years, the low-lying city with a population of more than 20 million has had to pour billions of dollars into rebuilding infrastructure to protect against potential floods. It is also revising its growth plans, hoping to reduce its vulnerabilities.
It has used its perch on the Yangtze River Delta to become one of the world's prime financial and shipping centers, but now it also finds itself being menaced by other hazards rooted in climate change. During the past years, the city has suffered more extreme weather, missed rain during the normal wet season and seen a temperature hike almost four times higher than the global level.
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Shanghai keeps reinforcing riverside barriers, but sometimes it has also been the effort's worst enemy. To catch up with its population boom and support an economy that grows at a double-digit rate almost every year, the land-scarce city has dried up coastal wetlands and filled them with new factories and apartments in its never-ending hunt for more space.
This fuels the city's economy, but it is also weakening the battlefront against climate change, says Yang Fuqiang, a climate expert at the Natural Resources Defense Council. As bulldozers wiped out wetland flora, Shanghai lost its natural barriers that can mitigate erosion and absorb the shock of storm surges, Yang explained. He added that the city should start restoring wetlands instead of reclaiming them.
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http://www.nytimes.com/cwire/2011/09/27/27climatewire-shanghai-struggles-to-save-itself-from-the-s-43368.html