Dust, Pollen Abundance Affect Cloud Precipitation, Climate Change

Colorado State University researchers are studying the critical role that dust, pollen, and other aerosols play in the formation of precipitation in clouds.  Large aerosol particles in the atmosphere act as ice nuclei, which are required for precipitation to form.  According to a university press release, “variation in the numbers of ice nuclei due to changes in processes affecting emissions at the Earth’s surface or human influences, such as industrial pollution, can thus affect precipitation and the properties of clouds that determine their warming or cooling impacts on climate.”

These findings have implications for climate models, which generally assume that clouds form when atmospheric temperature and relative humidity reach critical thresholds, said the press release. The new data suggest that assumption oversimplifies the process —ice nuclei must be present as well.

Read the press release at http://www.news.colostate.edu/Release/5253.