The Enhancement and Validation of ESA products (eVe)

The Centre for Aerosol Remote Sensing (CARS) has long-standing collaborations with the leading companies producing instruments for the measurement of aerosols with remote sensing techniques.

One example of best practice is the collaboration with the Greek company Raymetrics S.A. to develop a reference lidar system to validate the ESA Aeolus satellite mission.

The Enhancement and Validation of ESA products (eVe) ^[1] is a depolarization lidar system developed for the European Space Agency (ESA) by Raymetrics S.A. in collaboration with National Observatory of Athens (NOA) and LMU CARS Unit.

The eVe lidar is a surface-based remote sensor that deploys light detection and ranging (lidar) techniques to detect and characterize atmospheric aerosols and clouds, aiming at providing the ESAAeolus mission with a flexible, mobile reference ground-based lidar system capable of delivering well-characterized fiducial reference measurements of aerosol optical properties. Aeolus was the first satellite mission to acquire profiles of Earth’s wind on a global scale, providing at the same time information on aerosols and clouds. These observations are being used to improve weather forecasts and climate models.

The system allows the measurement of all four Stokes elements, used to derive information about polarization, hence opening significant new opportunities for atmospheric aerosol studies and applications, such as the detection of optical activity originating in biogenic aerosols, the alignment of non-spherical particles such as dust, smoke, and volcanic ash, and the aerosol multiple scattering effects.

The new lidar system has been deployed in the Cape Verde islands along with other ground-based and airborne instrumentation of ACTRIS, to conduct the Joint Aeolus Tropical Atlantic Campaign (JATAC) ESA experiment to validate Aeolus. Furthermore, datasets will be used for the upcoming EarthCARE ESA mission and future satellite concepts (such as the Earth Explorer 11 Wivern candidate mission).

[1] For more info, please visit https://evelidar.eu. For more technical insights, please look at Paschou P. et al.: “The eVe reference polarisation lidar system for the calibration and validation of the Aeolus L2A product”, Atmos. Meas. Tech., 15, 2299–2323, 2022