Global observations of atmospheric wind profiles and aerosol profiles are significant for NWP, radiative forcing and air quality. Spaceborne Doppler Wind Lidars (DWLs) and High Spectral Resolution Lidars (HSRLs) are capable of measuring global wind and aerosol profiles. Before the operational application of spaceborne lidar systems, dedicated and strict calibrations and validations (CAL/VAL) activities have to be conducted. This project will focus on the CAL/VAL and data assessment of three spaceborne lidar missions, which are ALADIN onboard Aeolus, ATLID (Atmospheric Lidar) onboard EarthCARE (Earth Cloud, Aerosol and Radiation Explorer), both initiated by the European Space Agency (ESA), and ACDL (Aerosol and Carbon Detection Lidar) onboard DQ (Daqi)-1, developed by Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences.
Aeolus was the first satellite mission to acquire profiles of Earth’s wind on a global scale. It was launched on 22 August 2018 and finished its nominal lifetime on 30 April 2023 before an assisted re-entry on 28 July 2023. The Aeolus satellite’s only payload is a direct detection DWL ALADIN. During its lifetime, it has measured the global wind profiles and aerosol profiles simultaneously and continuously for more than 4 years. The reprocessing of the Aeolus data products to improve data quality will continue in the next 5 years during phase F.
The launch of ESA’s EarthCARE satellite is scheduled for May 2024. The spacecraft will carry four instruments: the Cloud Profiling Radar (CPR) with Doppler capability, the Atmospheric Lidar (ATLID) with HSRL capability, the Multi-Spectral Imager (MSI), and the Broad-Band Radiometer (BBR). The satellite measurements will be used to retrieve global profiles of cloud, aerosol, and precipitation properties along with Top-Of-Atmosphere (TOA) Long- and Short-wave fluxes. The HSRL payload ATLID will provide vertical profiles of aerosols and thin clouds. It will operate at a wavelength of 355 nm and have a high-spectral resolution receiver and depolarization channel.
The Chinese atmospheric environment monitoring satellite DQ-1 has been successfully launched on 16 April 2022. As an integrated detection scientific research satellite, it will serve as an important part of Chinese atmospheric environment monitoring system. The DQ-1 equips five sensors including an Aerosol and Carbon Detection Lidar (ACDL), a Particulate Observing Scanning Polarimeter (POSP), a Directional Polarization Camera (DPC), an Environmental trace gas Monitoring Instrument (EMI) and a Wide Swath Imaging system (WSI). As the primary payload among them, ACDL is a HSRL with two-wavelength polarization detection, that can be utilized to derive the aerosol optical properties. The aerosol and cloud optical properties products of the ACDL include total depolarization ratio, backscatter coefficient, extinction coefficient, lidar ratio and color ratio. At present, DQ-1 is still in the commission phase and the products of ACDL are under calibration and validation (CAL/VAL).
To guarantee the data quality and refine the retrieval algorithms, an assessment of Aeolus’ reprocessed data needs to be conduct, whereas CAL/VAL campaigns for ATLID and ACDL products needs to be implemented.
In this project, we will use ground-based, airborne and shipborne lidar measurements to calibrate and validate the simultaneous observations from ALADIN, ACDL and ATLID. Besides, we will finish perform an assessment of their products via direct intercomparisons. The main instrumentation will be involved in this project include: Spaceborne lidar ALADIN on board Aeolus satellite, spaceborne lidar ATLID on board EarthCARE satellite, EARLINET within ACTRIS, PollyNet within EARLINET/ACTRIS, mobile ACTRIS aerosol and cloud remote sensing platforms of TROPOS (OCEANET, LACROS), and eVe reference lidar system of ESA from European side; Spaceborne lidar ACDL on board DQ-1 satellite, Coherent Doppler Lidars (CDLs) net (including more than 200 CDLs) over China, Direct detection Doppler Lidar (HSRL), polarization and Raman lidar Water vapor, Cloud and Aerosol Lidar (WACAL), Direct Spectrum Measurement Lidar (DSML) from Chinese side.
The expected results will include the assessment report (seasonal and annual) for the Aeolus reprocessed data and the validation results of the ACDL and ATLID by comparing with the airborne, shipborne and ground-based lidars.
Authors: Wu, Songhua (1);
Wandinger, Ulla (2);
Chen, Weibiao (3);
Liu, Jiqiao (3);
Xu, Na (4);
Dai, Guangyao (1);
Zhai, Xiaochun (4);
Baars, Holger (2);
Bley, Sebastian (2);
Reitebuch, Oliver (5);
Fix, Andreas (5);
Witschas, Benjamin (5);
Amiridis, Vassilis (6);
Marinou, Eleni (6);
Sun, Kangwen (1);
Long, Wenrui (1);
Meng, Fanqian (1);
Floutsi, Athena Augusta (2);
Trapon, Dimitri (2);
Genauer, Henriette (6);
Rizos, Konstantinos (6);
Voudouri, Kelly (6)
Organisations: 1: College of Marine Technology, Ocean University of China, Qingdao, China;
2: Leibniz Institute for Tropospheric Research, Leipzig, Germany;
3: Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China;
4: National Satellite Meteorological Center, China Meteorological Administration, Beijing, China;
5: Institute of Atmospheric Physics, Deutsches Zentrum f. Luft- u. Raumfahrt, Wessling, Germany;
6: National Observatory of Athens, Athens, Greece