First Ever Long-Term Aircraft Measurements of Clouds
A long-term, aerial field campaign to sample low-altitude, liquid-water clouds will begin January 23 at the Southern Great Plains Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) in Oklahoma. Different from the typical short duration aircraft campaigns, the campaign will run for six months to obtain, for the first time, representative in situ statistics of cloud properties and their seasonal variations, information needed for model improvements. The campaign will obtain representative statistics of the physical and radiative properties of low-level, liquid-water clouds to address aerosol-cloud interactions and improve cloud simulations in climate models. Currently there are large discrepancies in the radiative responses simulated by models in regions dominated by low-level cloud cover, and large areas of the globe are covered by these regions. Further, the properties of thin, low-level clouds are very sensitive to changes in aerosol loading and the aerosol effect on the reflectivity of clouds is a dominant uncertainty in radiative forcing.