<<Profiling of Clouds>>

S01 - O05
Analysis of a Multi-year Cloud Property and Radiative Heating Rate Dataset in the Arctic

David Turner1, M.D. Shupe2

1University of Wisconsin - Madison
2University of Colorado

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Abstract
The Arctic energy balance is very sensitive to clouds and their impact on the radiative fluxes. Relatively small changes in the macro- and microphysical properties of the clouds can have significant impacts on the radiative affect of the clouds on both the surface and atmosphere.
We have developed a comprehensive cloud product dataset that provides the macro- and microphysical properties of all clouds over the Atmospheric Radiation Measurement (ARM) program's North Slope of Alaska (NSA) site in Barrow, Alaska. This dataset was constructed by utilizing a conditional retrieval framework to derive the cloud existence, phase, condensed water content, and particle size for both the liquid and ice hydrometeors throughout the troposphere using a combination of active and passive ground-based observations.
Radiative heating rate profiles, as well as surface and top-of-the-atmosphere fluxes, have been computed for multiple years of data collected at the NSA site. These radiation calculations utilize the profiles of atmospheric state and cloud properties. The computed surface and top-of-the-atmosphere fluxes are compared against observations at the surface site and by satellite overpasses; the statistics demonstrate that the retrieved cloud properties are reasonable. The radiative heating rate profiles are then analyzed as a function of water content, phase, height, solar zenith angle, and season to provide insight into the radiative impact of these clouds on the atmosphere and surface.