BOULDER--Rescuers are using a weather prediction system specially designed for Antarctica as they try to evacuate an ill employee from the South Pole this week. With a computer forecasting model at its core, the Antarctic Mesoscale Prediction System (AMPS) is a collaboration between scientists at the National Center for Atmospheric Research and Ohio State University’s Byrd Polar Research Center. AMPS runs at NCAR and is funded by the National Science Foundation, NCAR's primary sponsor. High winds have so far prevented a twin-engine airplane from departing the British Rothera Base at the edge of Antarctica for the 1,500-mile, 10-hour flight inland to the pole. When winds abate, the crew will evacuate the ill employee to Rothera Base or to the U.S. base at McMurdo, depending on weather conditions. Meteorologists involved in the rescue are using AMPS for forecast information because it’s unique among weather prediction systems. While scientists develop and test most computer weather models for tropical and midlatitude regions, the poles present different challenges, such as a scarcity of weather stations to measure atmospheric conditions. AMPS uses a computer model called Polar MM5, primarily developed by the Polar Meteorology Group at the Byrd Polar Research Center, that is tailored for the extreme polar environment and takes account of features like sea ice. It incorporates a high amount of detail about Antarctica. "AMPS is not only breaking ground in the realm of real-time Antarctic weather modeling, but it is building a record of assisting in emergency rescues from Antarctica," says Jordan Powers, NCAR scientist and project lead for AMPS. Meteorologists used AMPS during the medical evacuation of an American scientist from the South Pole in 2001. In 2002, the model helped in the rescue of scientists and crew from a supply ship, the Magdalena Oldendorff, that became trapped in ice along the Antarctic coast. The ill employee has been spending the Southern Hemisphere winter at the South Pole to conduct research and run the station. The last flight left the pole in February and another isn’t scheduled to return until the Southern Hemisphere spring in late October. An attempted rescue flight on September 15 was cancelled because of bad weather at Rothera. When weather conditions are favorable, rescuers will make another attempt.