AMPS Update – July 2010 Kevin W. Manning Jordan G. Powers Mesoscale and Microscale Meteorology Division NCAR Earth System Laboratory National Center for Atmospheric Research, Boulder, CO NCAR is sponsored by the National Science Foundation AMPS is sponsored by the National Science Foundation – Office of Polar Programs 5th AMOMFW – Columbus, OH – July 2010

Antarctic Mesoscale Prediction System Funded by the NSF-OPP Experimental NWP system for Antarctica Using Weather Research and Forecasting Model (WRF) Advanced Research WRF (WRF-ARW) Formal collaboration among National Center for Atmospheric Research Ohio State University – Byrd Polar Research Center University of Colorado Informal interaction with many groups Officially in support of USAP forecasters We try to be useful to other groups doing Antarctic research and forecasting 5th AMOMFW – Columbus, OH – July 2010

What’s new this year AMSU-A radiance assimilation Correction to radiation scheme at model top (Powers presentation) CAM radiation physics (tried but then removed) Observations statistics (Wilson presentation) Real-time SOM product (CU) 5th AMOMFW – Columbus, OH – July 2010

AMSU-A Radiance Assimilation Advanced Microwave Sounding Unit Passes from several polar-orbiting satellites within a few hours of model initialization time Channels 5, 6, 7, 8, 9 – tropospheric temperatures Variational data assimilation in the WRF-VAR package with adaptive bias correction (Auligne et al., 2007) Attempts to distinguish between model bias and observations bias by taking into consideration other observation sources 5th AMOMFW – Columbus, OH – July 2010

AMSU-A Radiance Assimilation AMSU-A Data within 3 hours of 12 UTC, 01 Jul 2010 Before WRFVAR screeningAfter WRFVAR screening 5th AMOMFW – Columbus, OH – July 2010 NOAA-18 NOAA-15 NOAA-16 METOP-2

AMSU-A Radiance Assimilation 5th AMOMFW – Columbus, OH – July 2010 BIASRMSEBIASRMSE Test Period – 20 December 2009 through 25 January 2010 Forecast hour 0 (i.e., analysis time)Forecast hour Temperature statistics – verification against all Antarctic radiosonde reports With AMSU Without AMSU

AMSU-A Radiance Assimilation 5th AMOMFW – Columbus, OH – July 2010 BIASRMSEBIASRMSE Forecast hour 0 (i.e., analysis time)Forecast hour 48 With AMSU Without AMSU Test Period – 20 December 2009 through 25 January 2010 Temperature statistics – verification against South Pole radiosonde reports

CAM Radiation Schemes LW and SW Radiation physics packages from the NCAR Community Atmospheric Model are options in WRF-ARW CAM is the atmospheric component of NCAR’s Community Climate System Model (CCSM) Tested in Antarctica with good results Prompted by Arctic results of Mark Seefeldt and John Cassano, reported at last year's workshop Implemented in the AMPS real-time forecasts in October 2009 Problems arose in the real-time configuration Mysterious model / computer failures Changes reverted in December 2009 (RRTM LW, Goddard SW) 5th AMOMFW – Columbus, OH – July 2010

CAM Radiation Tests Consistency from forecast to forecast, but significant near-surface warm bias in summer, especially at elevated sites. Ad hoc adjustment of the snow albedo improved matters Varied albedo from 75 % near sea level to 80 % at 2500 m and above. 5th AMOMFW – Columbus, OH – July 2010

CAM Radiation Tests 5th AMOMFW – Columbus, OH – July 2010 RRTM LW GODDARD SWCAM LW CAM SW Temperature at AWS site Henry; January 2010

CAM Radiation Tests 5th AMOMFW – Columbus, OH – July 2010 Temperature at Byrd camp; January 2010 RRTM LW GODDARD SWCAM LW CAM SW

New real-time product The Self-Organizing Map (SOM) Self-Organizing Map of sea-level pressure in the Ross Sea region, from John Cassano et al. Offers forecasters a view of how well the model has performed in similar situations in the past 5th AMOMFW – Columbus, OH – July 2010

LARISSA one-way nest In support of forecasting for the LARISSA (Larsen Ice Shelf System, Antarctica) field campaign 2.5-km grid, initial and boundary conditions from the AMPS 5-km Antarctic Peninsula nest Grid active from 04 Jan through 08 Mar th AMOMFW – Columbus, OH – July 2010

NCAR is sponsored by the National Science Foundation Future? Transition to WRF Version 3.2 Some polar modifications ported into the supported WRF code Re-test CAM radiation schemes