Air pollution in Asia intensifies Pacific storms
The alarming amount of air pollution from fast-growing Asian economies isn’t solely a problem for China and its industrial neighbors. Airborne sulfate particles from coal-fired power plants and vehicle emissions are outnumbering natural aerosols like dust and sea salt in some places. And according to a new study, these anthropogenic aerosols are now crossing the ocean and intensifying cyclones over the Pacific. These pollutants could even alter weather patterns halfway around the world.
To study the impacts of these aerosols in the atmosphere, a team led by Yuan Wang from the Jet Propulsion Laboratory at Caltech built a climate model using IPCC data to simulate levels of pollutants from the pre-industrial era of 1850 and today. Their model showed that aerosols from Asian air pollution may travel downstream into the air above the Pacific Ocean. There, they alter the distribution of moisture and heat in the Pacific storm track, the major driver of weather in the Northern Hemisphere.
These tiny particles suspended in the air can change weather patterns so much because they scatter shortwave solar radiation and absorb longwave radiation. And when water vapor condenses around aerosols, that process changes the formation of clouds, making them denser and higher. The results, according to the model, are increased precipitation and the movement of heat from the tropics toward the poles.
These factors work together to boost the strength of cyclones in the mid-latitudes and invigorate the Pacific storm track. Exactly what that means for the future of weather in the U.S. is unclear; what’s clear is that air pollution is a global problem and shouldn’t be dismissed as merely a regional health crisis. — Janet Fang | 17 April 2014
Source: Wang, T. et al. Assessing the effects of anthropogenic aerosols on Pacific storm track using a multiscale global climate model, Proceedings of the National Academy of Sciences (2014). doi/10.1073/pnas.1403364111
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