A comprehensive validation of the Antarctic Mesoscale Prediction System (AMPS)

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). Model verification is integral to developing a system such as AMPS. Currently, a comprehensive validation is underway in order to examine the performance of AMPS since its inception. Verification statistics are presented to assess model strengths and weaknesses. At 24-h, the 30-km domain shows high skill in capturing the variability of temperature, geopotential height, and wind speed in the free atmosphere over all of Antarctica; it is less successful in capturing the moisture variability. Slightly lower skill is observed for temperature, pressure, and wind speed in the near-surface atmosphere. The lowest model skill for near-surface variables is observed in the area around Ross Island (the hub of U.S. operations), especially for wind speed, despite the use of higher resolution domains in this region. This indicates the need for improvement to model dynamics and/or model numerics and/or the interaction between nested domains.