Summer’s here, and it’s hot. Hot enough to fry an egg on the sidewalk.
Hot enough to… shut your body down and kill you within six hours?
A spike in heatwaves as a result of climate change could make one of China’s main agricultural regions the deadliest place on Earth.
The massive North China Plain, which spans 35 million acres across five provinces, from Beijing in the north to Shanghai in the east, is currently home to about 400 million people. It generates 20% of the country’s grains, according to the Chinese Academy of Sciences.
But according to a study by scientists at the Massachusetts Institute of Technology and published in the journal Nature Communications on Tuesday, the predicted heatwaves, caused by rising temperatures and increased humidity in the region, will make it almost uninhabitable before the end of the century.
“This spot is just going to be the hottest spot for deadly heatwaves in the future,” said Elfatih Eltahir, a hydrology and climate professor at MIT who led the research.
Such would be the intensity of the heat that healthy people could die after just hours of exposure to it, he said.
The heatwaves could spike what is known as “wet bulb” temperature, the study said. When this reaches 95°F (35°C), the heat and humidity, even in the shade, are so intense that the body cannot cool itself. Even perfectly healthy individuals can die within six hours.
Although the North China Plain is a major food production region, it does not receive much rainfall.
Farmers rely on irrigation systems during the spring and early summer growing season to nurture their crops, Eltahir said.
And while climate change was the main driver of the problem, “irrigation exacerbates the impact,” he said.
This is because the evaporation of irrigation water leads to higher humidity and because water vapor is itself a powerful greenhouse gas.
Such is the scale of irrigation use that it can add about one degree Fahrenheit to the wet bulb temperature.
Despite the undoubted effect of irrigation, Beijing and the rest of the world must reduce their carbon emissions if disaster is to be averted, Eltahir said.
“China is currently the largest contributor to the emissions of greenhouse gases, with potentially serious implications to its own population,” he said.
“But global society, not only China, should take serious steps to mitigate climate change.”
China has already seen evidence of rising temperatures over the past half a century.
The MIT study found the plain had experienced a significant increase in extreme heatwaves, including one in 2013 that lasted for 50 days and saw a 141-year temperature record in Shanghai smashed.
Between 1951 and 2006, the mean surface temperature across China rose by about 2.4 degrees Fahrenheit, a rate that was nearly twice the figure for the world as a whole, the study said.
The MIT research into the North China Plain was the third in a series of investigations into deadly heatwaves, with the previous two looking at the Persian Gulf and South Asia.
While both of those areas were found be at high risk, the threat level in China was the highest on Earth, the study said.
This story originally appeared on Inkstone, a daily multimedia digest of China-focused news and features. Like what you see? Sign up for our newsletter, download our app, or follow us on Twitter and Facebook.
Copyright (c) 2018. South China Morning Post Publishers Ltd. All rights reserved.
Source from MSN News
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