New weather prediction models improve forecast accuracy
23/04/2012
The Bureau of Meteorology has implemented a major upgrade of its global computer models this month, using cutting edge technology to better understand and predict our weather and climate.
Based on the Australian Community Climate and Earth System Simulator, or ACCESS, it has been developed in collaboration with the UK Met Office by scientists from the Bureau of Meteorology and CSIRO.
This ACCESS upgrade supports more accurate prediction of a range of forecasting services provided by the Bureau such as tropical cyclones and extreme rainfall events.
The project’s research leader, Dr Kamal Puri, says the ACCESS prediction system gives scientists and forecasters the best available scientific tools for weather forecasting and climate analysis, and contributes to ongoing improvements in forecast accuracy in the short to mid-term.
“The upgrade has vastly increased the available resolution, with the number of grid-points used to represent the global atmosphere up from 3 million to more than 20 million,” said Dr Puri.
“This higher resolution, combined with the use of sophisticated satellite measurements of the atmosphere, allows forecasters to better understand the influences likely to affect the weather over the coming days. In practical terms, this allows for more accurate forecasting of small-scale weather features, such as low pressure systems and cold fronts.
“The metrics used to test the new model demonstrate a huge leap in forecast accuracy: the accuracy for three days ahead is now the same as it was for two days ahead.
“One of the great benefits of ACCESS is that it operates across a huge scale, and can provide specific, high resolution forecasts for major cities or regions within Australia, and also work on a much larger, global scale,” said Dr Puri.
The head of the Bureau of Meteorology National Meteorological and Oceanographic Centre,
Mr Chris Ryan, says the ACCESS prediction system upgrade introduces a suite of new models that support improved warnings for a range of weather events such as tropical cyclones, assisting in better emergency planning and management.
The tropical cyclone forecasting capability of ACCESS accurately predicted severe tropical cyclone Lua; a category 4 cyclone that crossed the Pilbara coast of Western Australia last month.
“Tropical Cyclone Lua did loops before finally crossing the coast, and decaying into a low pressure system. ACCESS supported our forecasters in predicting just about every twist and turn, intensification and decline, at least a day and sometimes up to three days before it happened,” said Mr Ryan.
