About

the EVE lidar

The Enhancement and Validation of ESA products (eVe) 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 Ludwig-Maximilians University of Munich (LMU). It is an innovative, mobile system which consists of a dual-laser/dual-telescope configuration. It enables the simultaneous emission of linearly and circularly polarized radiation at 355 nm and the detection of the elastically backscattered radiation with polarization sensitive channels, as well as the inelastic (Raman) backscattered radiation at 387 nm. EVE aims to provide the ESA-Aeolus mission with a flexible, mobile reference ground-based lidar system capable of providing well-characterized fiducial reference measurements of aerosol optical properties. Morover, it can be upgraded to multi-wavelength system to support calibration/validation activities of the ATLID  lidar on-board the upcoming  EarthCARE satellite.

ALADIN

ALADIN onboard ESA-Aeolus satellite mission, is a Doppler Wind Lidar (DWL) operating in the ultraviolet region of the spectrum (355 nm), implemented in a transceiver configuration and tilted 35°  from nadir in order to provide line-of-sight wind profiles. It is also a High Spectral Resolution Lidar (HSRL), capable of deriving aerosol optical parameters such as backscatter and extinction coefficient profiles as well as the extinction-to-backscatter (lidar) ratio at 355 nm. ALADIN emits circularly polarized radiation but detects only the co-polarized component of the backscattered radiation. This limitation has almost negligible impact when spherical aerosol particles are probed. However, when non-spherical, depolarizing particles, such as desert dust, volcanic ash, and ice crystals are present, an uncertainty introduced on the aerosol backscatter coefficient retrieval due to the misdetection cross-polarized component.

EarthCARE

EarthCARE is an upcoming multi-instrument satellite mission aiming to  advance our understanding of the role that clouds and aerosols play in reflecting incident solar radiation back into space and trapping infrared radiation emitted from Earth’s surface. The mission will employ high-performance lidar (ATLID) and radar technology that has never been flown in space before.

EarthCARE will deliver unprecedented datasets to allow scientists to study the relationship of clouds, aerosols and radiation at accuracy levels that will significantly improve our understanding of these highly variable parameters.

 

Further reading

You can get further technical info for the EVE lidar in the following publication:

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.