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ASM Project Update: Atmospheric Modeling. John J. Cassano and Mark W. Seefeldt University of Colorado Cooperative Institute for Research in Environmental Sciences Department of Atmospheric and Oceanic Sciences. Goals for Year 1 of DOE Project. Develop and evaluate Polar WRF
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ASM Project Update:Atmospheric Modeling John J. Cassano and Mark W. Seefeldt University of Colorado Cooperative Institute for Research in Environmental Sciences Department of Atmospheric and Oceanic Sciences
Goals for Year 1 of DOE Project • Develop and evaluate Polar WRF • Univ. of Colorado • Sub-contract to Bromwich / Hines - OSU • Coupling of WRF to CCSM cpl7 • Lead by Juanxiong He, UAF
Strategy for Polar WRF Development • Use lessons from development of Polar MM5 • Identify parameterizations that are well-suited for polar use • Preference for parameterizations that are most physically realistic • Add “missing” physics • Collaboration with several research groups • OSU / BPRC • NOAA ESRL • NCAR • University of Colorado
Polar WRF Evaluation • Evaluate over a variety of polar surface types • Ice sheet (Hines / Bromwich - Greenland) • Sea ice / ocean (Hines / Bromwich and CU - SHEBA) • Implementation of fractional sea ice treatment (OSU) • Non-ice covered land • Evaluate atmospheric state • Evaluate atmospheric processes • Are we getting the right answer for the right reasons? • Initial work at University of Colorado • Identify parameterizations that are inappropriate for polar use • Identify “ideal” suite of model parameterizations • Identify aspects of model in need of improvement
SHEBA Simulations • Simulations during SHEBA year • January and June 1998 (CU) - climate mode • January, June, and August 1998 (OSU) - forecast mode • Model forcing (CU) • ECMWF TOGA atmospheric data and SST • ERA40 sea ice andsoil state • Model grid (CU) • 50 km horizontal • 31 vertical levels • Model top: 50 mb
WRF Physics • Land surface: Noah (Thermal diffusion) • Longwave radiation: RRTM • Shortwave radiation: Goddard (Dudhia) • Boundary layer: YSU (MYJ) • Microphysics: Morrison (WSM5) • Cumulus: Kain-Fritsch (Grell-Devenyi) • Bromwich / Hines have used a slightly different selection of model physics for their Greenland and SHEBA simulations
Shortwave Radiation: Goddard and Dudhia June 1998 Goddard SW RRTM LW WSM5 MP KF CU YSU PBL Noah LSM Dudhia SW
Land surface: Noah LSM and thermal diffusion January 1998 Noah LSM Dudhia SW RRTM LW WSM5 MP KF CU YSU PBL Thermal diffusion model
Cumulus: Kain-Fritsch and Grell-Devenyi June 1998 Kain-Fritsch Goddard RRTM LW Morrison MP MYJ PBL Noah LSM Grell-Devenyi
Cumulus: Kain-Fritsch and Grell-Devenyi June 1998 Kain-Fritsch Goddard RRTM LW Morrison MP MYJ PBL Noah LSM Grell-Devenyi
Cumulus: Kain-Fritsch and Grell-Devenyi June 1998 Kain-Fritsch Goddard RRTM LW Morrison MP MYJ PBL Noah LSM Grell-Devenyi
Boundary Layer: YSU and MYJ January 1998 YSU Goddard RRTM LW Morrison MP KF CU Noah LSM MYJ
Cloud Microphysics: Morrison and WSM5 January 1998 Morrison Goddard RRTM LW KF CU YSU PBL Noah LSM WSM5
Cloud Microphysics: Morrison and WSM5 June 1998 Morrison Goddard RRTM LW KF CU YSU PBL Noah LSM WSM5
Polar WRF and Polar MM5 January 1998 Polar WRF Goddard RRTM LW Morrison MP KF CU YSU PBL Noah LSM Polar MM5
Polar WRF and Polar MM5 January 1998 Polar WRF Goddard RRTM LW Morrison MP KF CU YSU PBL Noah LSM Polar MM5
Polar WRF and Polar MM5 June 1998 Polar WRF Goddard RRTM LW Morrison MP KF CU YSU PBL Noah LSM Polar MM5
Polar WRF and Polar MM5 June 1998 Polar WRF Goddard RRTM LW Morrison MP KF CU YSU PBL Noah LSM Polar MM5
Polar WRF and Polar MM5 June 1998 Polar WRF Goddard RRTM LW Morrison MP KF CU YSU PBL Noah LSM Polar MM5
Conclusions: Polar WRF Development • Some WRF physics options are clearly inappropriate for polar applications • Dudhia SW: large negative bias in SWD • Thermal diffusion soil model: large warm bias • There appear to be issues with other physics options, which need more analysis • Grell-Devenyi cumulus: excessive cloud cover • MYJ PBL: wintertime cold bias • Polar WRF has better skill than PMM5 for Jan • Polar WRF has similar skill as PMM5 for June • Processes in Polar WRF appear more realistic than in Polar MM5
Meetings, Presentations, and Publications • Conferences • DOE CCPP Science Team Meeting (Sept 07) • Poster overview of RACM project • SEARCH for DAMOCLES (Oct 07) • Atmospheric Modeling in an Arctic System Model • Polar Optimized WRF • Little Alaska Weather Symposium (May 08) • Development and evaluation of Polar WRF • Publications • Bromwich, D.H., K.M. Hines, and L.-S. Bai, 2008: Development and testing of Polar WRF. Part II. The Arctic Ocean, submitted to J. Geophys. Res.