Top weather forecaster ramps up computing power for predictions

Paris

THE European Centre for Medium-range Weather Forecasts (ECMWF), one of the most accurate predictors of global weather, is upgrading its supercomputer to improve its models and fine-tune predictions of extreme weather.

ECMWF spokesman Hilda Carr said: "Upgrading our computers is something that we do at regular intervals, but the intensification of severe weather and its impact is making this need more tangible.

"Our users need us to be more and more accurate and reliable as weather continues to kill and destroy."

In practice, the upgrade will lead to "significant improvements" in forecasts of temperatures and wind, as well of extreme events such as maximum rainfall intensity in extra-tropical storms and the strength of tropical cyclones, she said.

France's Atos signed a four-year contract worth more than 80 million euros (S$120 million) to supply the Reading, UK-based centre with a new supercomputer, to be built in Bologna, Italy. The system should be operational next year, said Atos spokesman Laura Fau.

Scientists have linked climate change to Australia's devastating bushfires, Arctic temperatures of more than 30 deg C this past summer, as well as record rainfall during Hurricane Harvey in Texas in 2017. Heatwaves and floods that used to be "once in a century" events are becoming more regular occurrences, noted the World Meteorological Organization (WMO).

ECMWF's new supercomputer will enable it to produce more detailed forecasts for smaller areas, dropping its 15-day forecasts from 18 to 10 km grids. The forecasts will also include more atmospheric layers in its models, the intergovernmental organisation said. Extended-range forecasts for four to six weeks ahead can be produced daily instead of twice a week.

Said Ms Carr: "Our science evolves continuously. There are more and more satellite observations that we want to process, our codes become more complex because they use many Earth system components, and we still have to get the data to our member states within one hour, so more computing capability will help."

Over the past 15 years or so, ECMWF forecasts have tended to be the most accurate, going by verification data by the WMO.

Atos is supplying a BullSequana system that would boost the ECMWF's computing capacity by five times from the current 8,500 teraflops (a teraflop is a unit of computing speed equal to one trillion calculations per second). This would place the system among the world's top 10 supercomputers, based on the Top 500 supercomputer ranking. BLOOMBERG