China’s air pollution cuts linked to faster global warming, finds study

Efforts to reduce air pollution in East Asia, especially China, may be unintentionally accelerating global warming, as per a study.

The article, titled “East Asian aerosol cleanup has likely contributed to the recent acceleration in global warming”, was conducted by Bjørn H Samset of the CICERO Center for International Climate Research in Oslo, and was published in Nature.com.

According to the study, global surface warming has picked up pace since around 2010, coinciding with aggressive pollution control measures in East Asia, particularly reductions in sulfate aerosol emissions.

Using simulations from eight Earth System Models, the study shows that a 75% reduction in these emissions has partially ‘unmasked’ the warming effect of greenhouse gases. Aerosols typically reflect sunlight and have a cooling effect, so cutting them reduces this masking, allowing more heat to reach the Earth’s surface.

The findings suggest that this cleanup has contributed to an additional global temperature rise of about 0.07 ± 0.05°C, making it a significant factor behind the recent acceleration in warming.

Researchers also observed warming trends in the North Pacific and an energy imbalance at the top of the atmosphere, both of which align with recent real-world observations.

The study was based on simulations conducted under the Reduced Aerosol Model Intercomparison Project (RAMIP), part of the broader CMIP6Plus climate modelling framework, comparing scenarios with high and low aerosol emissions.

The authors conclude that while reducing air pollution has clear health and environmental benefits, it may also have the side effect of accelerating global warming in the short term, highlighting the complex balance between air quality policies and climate change.