Looking Into CALIPSO Climatological Products: Evaluation and Suggestions from EARLINET

¹ Consiglio Nazionale delle Ricerche – Istituto di Metodologie per l’Analisi Ambientale (CNRIMAA), Potenza, Italy
² Andalusian Institute for Earth System Research, University of Granada (IISTA-CEAMA), Spain
³ Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, National Observatory of Athens, Greece
⁴ Centro de Geofísica de Évora (CGE), Évora, Portugal
⁵ Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia, Napoli Research Unit, Italy
⁶ Leibniz Institute for Tropospheric Research, Leipzig, Germany

^* Email: nikolaos.papagiannopoulos@imaa.cnr.it

Published online: 7 June 2016

Abstract

CALIPSO (Cloud-Aerosol Lidar and Pathfinder Satellite Observations) Level 3 (CL3) data were compared against EARLINET (European Aerosol Research Lidar Network) monthly averages obtained by profiles during satellite overpasses. Data from EARLINET stations of Évora, Granada, Leipzig, Naples and Potenza, equipped with advanced multi-wavelength Raman lidars were used for this study. Owing to spatial and temporal differences, we reproduced the CL3 filtering rubric onto the CALIPSO Level 2 data. The CALIPSO monthly mean profiles following this approach are called CALIPSO Level 3*, CL3*. This offers the possibility to achieve direct comparable datasets. In respect to CL3 data, the agreement typically improved, in particular above the areas directly affected by the anthropogenic activities within the planetary boundary layer. However in most of the cases a subtle CALIPSO underestimation was observed with an average bias of 0.03 km-1. We investigated the backscatter coefficient applying the same screening criteria, where the mean relative difference in respect to the extinction comparison improved from 15.2% to 11.4%. Lastly, the typing capabilities of CALIPSO were assessed outlining the importance of the correct aerosol type (and associated lidar ratio value) assessment to the CALIPSO aerosol properties retrieval.