Climate impacts of air pollution studied

Increased air pollution can worsen both droughts and flooding simultaneously in different regions by strongly affecting cloud development. U.S. researchers say. University of Maryland researchers say their study found clear evidence of how aerosols -- soot, dust and other small particles in the atmosphere -- can affect weather and climate, reducing precipitation in dry regions or seasons while increasing rain, snowfall and the intensity of severe storms in wet regions or seasons. "We have uncovered, for the first time, the long-term, net impact of aerosols on cloud height and thickness, and the resultant changes in precipitation frequency and intensity," Zhanqing Li, professor of atmospheric and oceanic science, said in a university release. "Our findings have significant policy implications for sustainable development and water resources, especially for those developing regions susceptible to extreme events such as drought and flood," Li said. Greenhouse gases and aerosol particles are two major agents dictating climate change, and while the mechanisms of climate warming impacts of increased greenhouse gases are clear, the climate effects of increased aerosols have been much less certain, the researchers said. "These new findings of long-term impacts ... attest to the needs of tackling both climate and environmental changes that matter so much to our daily life," Li said.