Global warming? Global cooling!
Atmospheric researchers have provided observational evidence that burning fossil fuels has a direct impact on the solar radiation reflectivity of clouds, thereby contributing to global climate change.
Joyce Penner, professor in the University of Michigan Department of Atmospheric, Oceanic and Space Sciences, U-M graduate student Yang Chen, and assistant professor Xiquan Dong from the University of North Dakota Department of Atmospheric Science, reported their findings in the Jan. 15 issue of the journal Nature.
Most evidence that increased levels of fossil fuel particles (aerosols) affects the reflectivity of clouds, thereby producing a cooling effect on the climate, has been indirect. “This made it difficult to determine the impact this phenomena, known as the indirect aerosol effect, has on the global climate,” Penner said. “Our data makes the direct connection and opens new areas of study.”
Solar radiation, which adds to global warming, is reflected back into space by clouds. Cloud droplets are increased with higher levels of aerosols, allowing for less radiation, or heat, to reach the lower atmosphere. The end result is a measurable cooling effect on the climate.