Why did acid rain become a major environmental issue in Europe and North America after World War II?

Acid rain became a major environmental issue in Europe and North America following World War II primarily due to the rapid expansion of industrial activities that lacked adequate emission controls.12

The surge in the burning of fossil fuels—such as coal, oil, and natural gas—by electrical utilities and industrial sectors released vast quantities of sulfur dioxide and nitrogen oxides into the atmosphere. These chemical compounds react in the air to form acidic precipitation, which can fall as rain, snow, fog, or dry particles far downwind from the original emission sources.12

During the post-war period, the absence of strict environmental regulations allowed these pollutants to accumulate, leading to widespread ecological damage, including the acidification of freshwater lakes, the depletion of soil nutrients, and the deterioration of forests and historic monuments. The issue gained significant public and scientific recognition by the late 1960s and 1970s, eventually prompting the implementation of effective air quality policies, such as the U.S. Clean Air Act of 1970, which successfully reduced emissions and mitigated the problem in these regions.123