Using ASR Observations to Quantify the Seasonal Influence of Stratiform Mixed-phase Clouds on Arctic Sea Ice Growth Rates

Gijs de Boer University of Colorado, Boulder/CIRES
William Collins Lawrence Berkeley National Laboratory
Edwin Eloranta University of Wisconsin
Surabi Menon Lawrence Berkeley National Laboratory
Elizabeth Hunke Los Alamos National Laboratory

Category: Atmospheric State & Surface

Working Group: Cloud-Aerosol-Precipitation Interaction

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A graphical overview of the proposed study.

Single-layer stratiform clouds are commonly observed at high latitudes (de Boer et al. 2009; Shupe et al. 2006, others). Recently several papers have linked record minimum sea ice coverage in part to anomalous patterns in low cloud coverage (e.g., Kay et al. 2008). Low-level mixed-phase clouds may impact sea ice growth/melting rates via their influence on the atmospheric radiation budget as well as through frozen precipitation they produce. These influences are naturally variable by season, dependent largely upon sun angle and atmospheric temperature. In this study, we plan to utilize multiple years of cloud observations from surface-based remote sensors at Barrow, Alaska (United States Department of Energy Atmospheric Radiation Measurement (U.S. DOE ARM) North Slope of Alaska site) and Eureka, Canada (National Oceanographic and Atmospheric Administration and Canadian Network for the Detection of Arctic Change/Study for Environmental Arctic Change (NOAA/CANDAC SEARCH) program) to derive seasonal estimates of surface radiative and precipitation fluxes using measured cloud properties such as liquid water content, ice water content, precipitation rate, temperature, and cloud depth. The radiative flux estimates are obtained with the help of an atmospheric radiative transfer model (RRTM, Clough et al. 2005), and tested for a limited number of cases using radiometer data from the NSA site. Finally these fluxes, along with relevant temperature and precipitation information, are used to drive the Los Alamos Sea Ice Model (CICE, Hunke and Lipscomb 2008) to determine the influence of these clouds on sea ice growth rates. We will present an overview of the proposed work, along with some preliminary results and a vision for future investigations involving other cloud types.

This poster will be displayed at ASR Science Team Meeting.

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