NCEO’s Director, John Remedios, excitedly witnessed the successful launch of the Aeolus satellite from Kourou at the Spaceport in French Guiana on 22nd August at 22.20 hours.
Built in Britain by Airbus, Aeolus is a European Space Agency-organized mission to provide much-needed data in improving the quality of weather forecasts and contributing to long-term climate research. The satellite carries a laser Doppler wind LIDAR (Light Detection and Ranging) system called Aladin that will probe the lowermost 30 km of the atmosphere in measuring winds around the Earth.
John Remedios explained “The molecules in the air and the clouds move with the wind and that motion causes a shift in the frequency of the return signal. The laser sends out a signal at one frequency and you get it back at a slightly different frequency. It’s called the Doppler effect and you’ll be familiar with it from the usual story of how an ambulance siren changes as it passes you in the street”.
Aeolus will gather wind data across the entire Earth, from the ground to the stratosphere (30km), providing data to weather forecasters a few days ahead. Aeolus does this by firing an ultraviolet laser through the atmosphere and measuring the return signal using a large telescope. The light beam gets scattered back off air molecules and small particles moving in the wind at different altitudes. Meteorologists will adjust their numerical models to match the information gathered by the satellite, improving accuracy. The biggest impacts are expected on medium-range forecasts – those that look at weather conditions a few days hence.
BBC’s Jonathan Amos wrote “Aeolus is only a demonstration mission but it should blaze the trail for future operational weather satellites that use lasers”.
Read BBC Jonathan Amos’ article here