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CLOUD experiment
Aerosol nucleation experiment at CERN / From Wikipedia, the free encyclopedia
Cosmics Leaving Outdoor Droplets (CLOUD)[1] is an experiment being run at CERN by a group of researchers led by Jasper Kirkby to investigate the microphysics between galactic cosmic rays (GCRs) and aerosols under controlled conditions. This is a fixed-target experiment that began operation in November 2009,[2] though it was originally proposed in 2000.[3]
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The primary goal is to understand the influence of galactic cosmic rays (GCRs) on aerosols and clouds, and their implications for climate. Although its design is optimised to address the possibility of cosmic rays nucleating cloud particles, (as posed by, for example, Henrik Svensmark and colleagues[4]) CLOUD allows as well to measure aerosol nucleation and growth under controlled laboratory conditions. Atmospheric aerosols and their effect on clouds are recognised by the IPCC as the main source of uncertainty in present radiative forcing and climate models, since an increase in cloud cover reduces global warming.