Scientists Make First Direct Observations of Biological Particles in High-Altitude Clouds Airborne dust and microbial matter appear to play large role in ice formation in clouds
A team of atmospheric chemists has moved closer to what's considered the "holy grail" of climate change science: the first-ever direct detections of biological particles within ice clouds.
A team of UC San Diego-led atmospheric chemistry researchers moved closer to what is considered the "holy grail" of climate change science when it made the first-ever direct detection of biological particles within ice clouds. The team, led by Kerri Pratt, a Ph.D. student of atmospheric chemistry Professor Kim Prather, who also holds appointments at Scripps Institution of Oceanography as well as the Department of Chemistry and Biochemistry at UCSD, sampled water droplet and ice crystal residues at high speeds from an aircraft flying through clouds in the skies over Wyoming in fall 2007. Analysis of the ice crystals revealed that they were made up almost entirely of either dust or biological particles such as bacteria, fungal spores and plant material. While it has long been known that microorganisms or parts of them get airborne and travel great distances, this study is the first to yield in-situ data on their participation in cloud ice processes. Results of the Ice in Clouds Experiment Layer Clouds (ICE-L), funded by the National Science Foundation (NSF) and the National Centre for Atmospheric Research (NCAR), appear May 17 in the advance online edition of the journal Nature Geoscience. Source University of California - San Diego
By sampling clouds - and making their own - researchers have shown for the first time a direct relation between lead in the sky and the formation of ice crystals that foster clouds. The results suggest that lead generated by human activities causes clouds to form at warmer temperatures and with less water. This could alter the pattern of both rain and snow in a warmer world. The lead-laden clouds come with a silver lining, however. Under some conditions, these clouds let more of the earth's heat waft back into space, cooling the world slightly. Atmospheric lead primarily comes from human sources such as coal.
Clouds that look like breasts Few will have seen a sky like it. Yet this extraordinary-looking cloud formation wasn't photographed in exotic climes, but in St Albans, Hertfordshire, on a recent August evening.