Why has acid deposition increased in parts of China and India?

The increase in acid deposition in parts of China and India is primarily driven by the significant expansion of coal combustion for industrial and electricity production since approximately 2000. This process releases sulfur dioxide (SO₂) and nitrogen oxides (NOₓ), which are the primary precursors to acid rain.12

In India, industrial activity—particularly from thermal power plants—is a major contributor to air pollution and acid rain. While the government has mandated the use of flue gas desulfurization (FGD) systems to mitigate these emissions, implementation has been slow, with very few units meeting compliance standards as of late 2024. Consequently, India’s SO₂ emissions have continued to rise.31

In contrast, China experienced a similar trend of increasing emissions until 2007, when the introduction of stringent emission controls led to a 75 percent decline in the country’s SO₂ emissions by 2019. It is a fundamental ethical imperative to prioritize the implementation of effective pollution controls to protect public health and the environment from the damaging effects of acid deposition.132