“Meteorologists urgently need reliable wind-profile data to improve accuracy,” the ESA said in a statement, according to Phys.org. Mission Aeolus will provide global observations of wind profiles from space that will improve the quality of weather forecasts, and advance our understanding of atmospheric dynamics and climate processes.
Of particular importance is the need for better tropical wind observations. There is currently an almost complete lack of direct observations, which makes tropical winds poorly mapped. And once Aeolus is in orbit, it will be able to retrieve data from anywhere on the planet, including remote areas without ground-based weather stations. Once per orbit, data is downloaded to a ground station in Svalbard, Norway.
Meet ALADIN – First ever space-LIDAR
There are lots of different ways to measure winds using satellites. However, Aeolus will utilize the active Doppler Wind Lidars (DWL) method, nick-named ALADIN. Lidar works by emitting a short, but powerful, light pulse from a laser through the atmosphere and then collects light that is backscattered from particles of gas and dust and droplets of water in the atmosphere, using a large 1.5m diameter telescope.
As the scattering particles are moving in the wind, the wavelength of the scattered light is shifted about a small amount, as a function of speed. Onboard highly sensitive receivers are then able to determine the Doppler shift of the signal from layers at different heights in the atmosphere.
The ESA says DWL is the only method with the potential to provide the required data globally, from direct wind observations. And as a useful by-product of DWL, scientists will also get information on cloud top heights, vertical distribution of clouds, aerosol properties, and wind variability.
Launch schedule for Aeolus mission
The 1,260-kilogram (3,000-pound) payload will be launched into a 320-kilometer (200-mile) orbit on a Vega rocket, with lift-off scheduled for Tuesday at 21:20 GMT (23:20 CEST).
Aeolus was sealed from view in its Vega rocket fairing last week, after which it was rolled out to the launch pad, hoisted into the launch tower and joined to the rest of the rocket. The new mission will be Arianespace’s 50th launch for the European Space Agency.
Aeolus is the fifth of the ESA’s planned Earth Explorer missions. Others in the program, already completed or in operation, have measured Earth’s gravity and geomagnetic fields, soil moisture, ocean salinity and frozen expanses collectively known as the cryosphere.
