TECH

Because the next generation of weather satellites will tear everything apart

Gossip will rejoice in more accurate weather reports. Scientists and forecasters are very enthusiastic. The first of the satellites weather report second generation Europeans, MetOp-SG with its little name, are assembled in clean rooms by Airbus Defense & Space (ADS) and will be launched “in October or November 2024”. No longer from a Russian Soyuz pitcher, but from an Ariane 6, given the new international context.

“It will be one of the most precise missions ever launched to study the atmosphere,” says Cyril Crevoisier, CNRS research director at the Dynamic Meteorology Laboratory (LMB) in Toulouse. Because, while using the same infrared techniques to probe the atmosphere, “an area where the French excel” is simply announced “twice as efficient” and accurate as the first wave of satellites. In particular thanks to the new generation (NG) of its main instrument – the IASI, for the infrared atmospheric sounding interferometer – “a jewel of technology” developed by CNES and Airbus engineers, and currently being integrated at the ADS in Toulouse.

Embedded on the satellite, IASI-NG it will allow us to probe the entire atmosphere of the Earth twice every 24 hours, from top to bottom, in bands 2,400 km long and 100 km wide. “By providing parameters such as temperature or water vapor columns, it will feed the Météo-France forecast models and improve them for several days,” stresses François Bermudo, CNES project manager. But the instrument will also be able to track polluting atmospheric molecules more finely. “Like ammonia in the event of an industrial fire,” says Cathy Clerbaux, of the Laboratory for the Observation of Atmospheres and Space (Latmos). Or the ashes during volcanic eruptions.

Sleeper for 15 years

As for climatologists such as Cyril Crevoisier, they will be able to study long-term climate change, using “extremely weak temperature signals, sometimes on the order of a hundredth of a degree”. “From the launch of the first IASI in 2006 to the latest IASI-NG scheduled for 2038, we will have a fifty-year atmospheric observation program with the same type of instrument. Therefore a homogeneity of the data ”, explains the researcher.

Beyond the expected performances, the IASI-NG has this originality that it will be produced one after the other in three copies, for three of the second generation MetOp satellites managed by the European Organization for the Exploitation of Meteorological Satellites (Eumetsat). The last instrument will then sleep for 15 years waiting for its flight.

Leave a Comment