This time last year, Aeolus was guided expertly home during a world first assisted re-entry. Though what remains of the satellite might be on Antarctic ice right now (most of it burned up in Earth’s atmosphere), Aeolus data are still improving our understanding of weather and atmospheric science.

In Spring 2024, the Aeolus data, science and innovation cluster (DISC) released a new public data update (Baseline 16), with a range of exciting new features, including much improved aerosol products – just in time for the launch of EarthCARE.

Aeolus, ESA's wind mission, provided the world's first ever vertical profiles of Earth's wind on a global scale thanks to its doppler lidar instrument ALADIN, which could also measure atmospheric aerosols such as dust and volcanic ash.

Nearly five years’ worth of Aeolus data drastically improved weather forecasts, particularly in the tropics, and shone a light on numerous global events from the Godzilla Saharan Dust plume of 2020 to the Hunga Tonga eruption of 2022.

The period covered by the data update, 28 June 2019 to 4 October 2022, includes some significant atmospheric aerosol events. In addition to those already mentioned, there were wildfires and bushfires in Siberia, Australia and California, throughout 2019 and 2020.

The Baseline 16 release involves new Level-2A aerosol products, some of which have been developed by KNMI (as part of the DISC) in parallel to the preparation of the EarthCARE mission, which launched in May 2024.

EarthCARE to a certain degree picks up the baton from Aeolus, thanks to its atmospheric lidar instrument ATLID. During Aeolus campaigns, lidar measurements were used to help prepare for the calibration and validation activities that will take place for EarthCARE.

This highlights the continued role for Aeolus in paving the way for its successors: EarthCARE; the operational Aeolus-2 mission planned for the 2030s; and the Earth Explorer 11 candidate mission WIVERN, which would measure winds in clouds.

Four key updates to Baseline 16 

• The Level-1B product includes new corrections for hot-pixel anomalies leading to higher quality of Level-2A and Level-2B products
• New Level-2A aerosol products at finer resolution down to ~3km horizontal have been activated: Aeolus Feature Mask (AEL-FM), Aeolus Profile (AEL_PRO) and Maximum Likelihood Estimation (MLEsub) with fine-tuned quality flags
• The Level-2B product quality has been significantly increased using optimised wind-bias correction
• The 2019 to 2022 dataset has been prepared taking into account in-orbit deviations and FM-B laser signal degradation

Providing the reprocessed dataset to users is a key objective of ESA, and the VirES for Aeolus research environment allows users easy access to view, analyse, and download data. Addition of the new Baseline 16 variables is ongoing and can be accessed via VirES.

This is just the beginning for Phase F of the Aeolus mission, and the Aeolus DISC will introduce further improvements between now and 2028. They will include reprocessed Baseline 16 FM-A data, scheduled for 2025, marking the first time we have a uniformly processed Aeolus dataset covering the entire mission.