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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.

The ReACT group of IAASARS has developed “WALL-E” lidar, a novel polarization lidar system capable of monitoring possible dust orientation and microphysical properties. WALL-E emits linearly- and elliptically-polarized light and detects the linear and circular polarization of the backscattered light from the dust particles in the atmosphere. It also employs scanning capabilities so as to provide more information on the dust orientation and microphysical properties. The system is designed based on the high quality standards of the European lidar network EARLINET, in the framework of ERC-COG program D-TECT.

CIMEL sunphotometer: CIMEL is a high-precision multiband, automatic sun-and-sky scanning radiometer that provides measurements of the optical properties of the atmosphere by measuring the sun and sky radiance. Due to its very low power consumption and its self-powered system, it meets the requirements of continuous monitoring in terms of reliability, long term and very low maintenance cost.

Most recent measurements of CIMEL Antikythera.

Polly-XT lidar: Multi-wavelength lidar for the 24/7 monitoring of the atmospheric state. The system enables the determination of the particle backscatter coefficient at 355, 532, and 1064 nm and of the extinction coefficient at 355 and 532 nm, allowing aerosol classification and microphysical characterization to derive the particle size distribution and concentration. In addition, the system operates two polarization-sensitive channels at 355 and 532 nm, to determine the aerosol particle shape from the (particle) linear depolarization ratio, to separate dust and non-dust particles in mixed aerosol layers, and to investigate mixed-phase clouds.

Most recent Measurements of PollyXT Antikythera.

Direct-sun Solar Polarimeter (SolPol): A prototype solar polarimeter, kindly conferred by the University of Hertfordshire, is designed to operate with direct sun tracking capabilities and measures the degree of linearly and/or circularly polarized sunlight due to forward scattering from atmospheric aerosols. Measurements are centered on 550nm, due to light detector current limitations, while the instrument’s precision and accuracy are of order of the 1ppm and 1%, respectively. SolPol is a robust instrument capable of manual operation per demand, especially under heavy Saharan dust loads and with low maintenance requirements. It is hosted within a medium sized astronomical dome for the optimum protection-to-applicability relation.

About Us

ReACT stands for “Remote sensing of Aerosols, Clouds and Trace gases”, to describe the research focus of the respective research team led by Dr. Vassilis Amiridis. ReACT consists of highly motivated scientists within the field of Atmospheric Sciences, combining a number of Post-doc researchers, Ph.D. and M.Sc. students as well as other research and technical staff, using the resources, infrastructure and experience of the Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing (IAASARS).

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