China’s Long Arm Reach of Acid Rain

Walking in the rain in Taiwan might not be as romantic as it is in the movies, especially in winter, when a northeasterly wind starts to blow. Last December, officials at the Central Weather Bureau found that several areas in northern Taiwan had been significantly affected by pollution. ... Bureau officials pointed to an extreme case of acidity recorded at 3.6 pH in value in Keelung. Bureau officials remind people to wear hats or use umbrellas to avoid going bald as a result of the acid rain, adding that the acidity of rain in Keelung was only slightly less acidic than vinegar.

—Taipei Times

By definition, acid rain is rain with a pH reading of less than 5.6 (where 7 is neutral). It occurs when the sulfur dioxide and nitrogen dioxide emissions from power plants burning fossil fuels react in the atmosphere with water, oxygen, and various chemicals to form sulfuric and nitric acids.

Why is acid rain so dangerous? Because it is a very efficient killer. Acid rain kills fish when it falls into lakes, rivers, and streams. It directly kills crops and damages soil and thereby substantially reduces harvests. It indirectly kills forests by weakening trees and making them more susceptible to diseases. Acid rain also reduces visibility and eats away at building materials, car paint, and roofing on houses—with the damages running into the billions of dollars annually.

Acid rain now falls over two-thirds of China’s land mass. Most of this acid rain is caused by sulfur dioxide emissions from China’s ubiquitous coal plants. However, China’s steel industry and its belching coking plants also play a big role in the problem.

As noted earlier, it is not just China and its people who are suffering. Roughly half of Japan’s acid rain and a smaller but significant fraction of Taiwan’s and the Korean Peninsula’s acid rain carries the “Made in China” label.