The performance of the Antarctic Mesoscale Prediction System (AMPS) for an intense summer storm in the Ross Sea

The Antarctic Mesoscale Prediction System (AMPS) is an experimental system run at the Mesoscale and Microscale Meteorology Division of the National Center for Atmospheric Research (NCAR) and dedicated to real-time numerical weather prediction in Antarctica (http://www.mmm.ucar.edu/rt/mm5/AMPS/). AMPS employs the Polar MM5, a version of the Pennsylvania State University/NCAR fifth generation mesoscale model (MM5) optimized for the environment of polar ice sheets by the Polar Meterology Group of the Byrd Polar Research Center at Ohio State University (http://www-bprc.mps.ohio-state.edu/PolarMet/pmm5.html). Here, the performance of AMPS is assessed for a severe weather event occurring in the Ross Sea in December 2001. Winds in excess of 100 kts, precipitation, and blowing/drifting snow caused aircraft operations at McMurdo Station, the hub of the U.S. Antarctic Program, to cease for about a week at the height of the operational season. Thus, it is important to evaluate model strengths and weaknesses for such an event. Plans include performing additional AMPS simulations using a 4-dimensional variational data assimilation scheme and incorporating novel data sources such as GPS radio occultations. These will be compared to simulations using the current AMPS configuration, and are expected to bring considerable improvement in model forecast skill and forecast lead-time.