The high-tech race to improve weather forecasting

Matteo Dell’Acqua has to shout to make himself heard. Engine Room Number Five at the European Centre for Medium-Range Weather Forecasts’ data centre in Bologna houses a series of motors, each turning a three-tonne flywheel. Should the electricity cut out, the flywheels—and those in four other rooms elsewhere in the building—have enough momentum to keep the ECMWF’s newest supercomputer running until the back-up diesel generators fire up.

Those generators have fuel for three days. A longer blackout would spell disaster. Weather shapes military campaigns and crop harvests, sports matches and supply chains. Losing access to the world’s most reliable weather forecast would drastically reduce the prescience and preparedness of more than 35 countries, NATO, at least one space agency and a great many research institutions and businesses. The operation must run constantly, says Mr Dell’Acqua, who is in charge of the whole affair. “It’s really critical.”