Researchers at the Royal Melbourne Institute of Technology's SPACE Research Centre and the Bureau of Meteorology are using GPS and low earth orbit satellites to provide an additional type of temperature profile observation for use in weather forecasting computer models. The computer models draw on about a hundred thousand million current weather observations, including data from 30 to 40 complementary satellite instruments, to generate the information used by meteorologists to prepare weather forecasts.
RMIT Adjunct Professor John Le Marshall explained: "What we've found through our work with RMIT's SPACE research team is that the GPS data improves the real-time temperature field and the cross-calibration of the data from a number of satellite instruments. This in turn significantly increases the usable quality of the satellite observations. We are actually able to measure the amount of bending in the GPS beam as it passes through the atmosphere. We can then use that knowledge to more accurately measure atmospheric temperatures and use this to improve temperature fields and calibrate other satellite readings. This extra information, in the data-sparse southern hemisphere, is now making our forecasts more accurate." He predicts that, as techniques improve, GPS data will also play a bigger role in climate monitoring and severe weather warnings.