ALEXANDRE CACHEFFO
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Resumo IPEN-doc 28961 Study of aerosol optical properties on South America using AERONET data analysis2021 - JESUS, ESTER O. de; ROSARIO, NILTON M.E. do; YOSHIDA, ALEXANDRE C.; CACHEFFO, ALEXANDRE; GUERRERO-RASCADO, JUAN L.; LANDULFO, EDUARDO; LOPES, FABIO J.S.In the last decade, a new generation of satellite missions have been developed using advanced lidar systems capable to retrieve several cloud and aerosol optical properties and distinguish different aerosol types by applying a polarization sensitive high spectral resolution lidar (HSRL) technique, as is the case of the Earth Clouds, Aerosols and Radiation Explorer (EarthCARE) mission, developed by the European Space Agency (ESA) together with the Japan Aerospace Exploration Agency (JAXA). The EarthCARE payload will be compound by four main instruments, a cloud profiling radar, with Doppler capability, the HSRL system, a multispectral imager and a broadband radiometer, enabling the retrieval of global profiles of clouds, aerosols, precipitation and radiation field properties. The Atmospheric Lidar system (ATLID) on board of EarthCARE will operate at 355 nm and will use the cross and co-polarized components of Mie and Rayleigh scattering to derive aerosol properties. An important task to be developed by ground-based research groups is the data validation process. In this context, the Latin American LIdar NETwork (LALINET) has been playing a key role in the cloud and aerosol studies by using lidar and/or the AERONET sunphotometers data. In order to prepare the most suitable strategy for calibration and validation (CAL/VAL) processes of the EarthCARE mission, we have employed an extensive study of aerosol optical properties derived from 21 AERONET sunphotometer stations all over South America, from a period of at least 20 year. The aim of this work is to present preliminary results of columnar aerosol optical properties, such as AOD, lidar ratio, scattering and absorption Angstrom Exponent, single-scaterring albedo and aerosol fine-mode fraction, in order to select cluster-zones by aerosol types to guide the validation methodology for ATLID system products, since the continent is dominated by high spatial and temporal variability of aerosol systems.Resumo IPEN-doc 28093 AEOLUS calibration and validation activities at SPU Lidar Station - Brazil2020 - YOSHIDA, A.C.; LOPES, F.J.S.; CACHEFFO, A.; MOREIRA, G.A.; SILVA, J.J. da; LANDULFO, E.Resumo IPEN-doc 27965 Validation of AEOLUS L2A products using a multiwavelength lidar system at SPU Lidar Station - Brazil2020 - LOPES, FABIO; YOSHIDA, ALEXANDRE; CACHEFFO, ALEXANDRE; SILVA, JONATAN; MOREIRA, GREGORI; LANDULFO, EDUARDOResumo IPEN-doc 27962 Overview of the 2019 Sentinel-5p TROpomi vaLIdation eXperiment (TROLIX)2020 - APITULEY, ARNOUD; KREHER, KARIN; PITERS, ANKIE; SULLIVAN, JOHN; VAN ROOZENDAEL, MICHEL; VLEMMIX, TIM; DEN HOED, MIRJAM; FRUMAU, ARNOUD; HENZING, BAS; SPEET, BART; VONK, JAN; VEEFKIND, PEPIJN; ALVES, DIEGO; CACHEFFO, ALEXANDRE; STEIN-ZWEERS, DEBORAH; ALLAART, MARC; ESKES, HENK; VAN DER ENT, FLORIS; SALEEB, GEORGE; MCGEE, TOM; TWIGG, LARRY; SUMNICHT, GRANT; HENDRICK, FRANCOIS; MERLAUD, ALEXIS; FAYT, CAROLINE; HERMANS, CHRISTIAN; PINARDI, GAIA; DORNER, STEFFEN; WAGNER, THOMAS; LAUSTER, BIANCA; UBELE, ALMA; MENDES, ALEX; LOPES, FABIO; LANDULFO, EDUARDO; SPINEI, ELENA; QUEREL, RICHARD; KARAGKIOZIDIS, DIMITRIS; BAIS, ALKIS; HUTJES, RONALDFor the validation of Sentinel-5p/TROPOMI the TROpomi vaLIdation eXperiment (TROLIX) was held in the Netherlands based at the Cabauw Experimental Site for Atmospheric Research during September 2019. TROLIX consisted of active and passive remote sensing platforms in conjunction with several balloon-borne and surface measurements. The intensive observations will serve to establish the quality of TROPOMI L2 main data products (UVAI, Aerosol Layer Height, NO2, O3, HCHO, Clouds) under realistic conditions with varying cloud cover and a wide range of atmospheric conditions. Since TROPOMI is a hyperspectral imager with a very high spatial resolution of 3.6 x 5.6 km2, understanding local effects such as inhomogeneous sources of pollution, sub-pixel clouds and variations in ground albedo is important to interpret TROPOMI results. Therefore, the campaign included sub-pixel resolution local networks of sensors, involving MAXDOAS and Pandora instruments, around Cabauw (rural) and within the city of Rotterdam (urban). Utilising its comprehensive in-situ and remote sensing observation program in and around the 213 m meteorological tower, Cabauw was the main site of the campaign with focus on vertical profiling using lidar instruments for aerosols, clouds, water vapor, tropospheric and stratospheric ozone, as well as balloon-borne sensors for NO2 and ozone. The data set collected can be directly compared to the TROPOMI L2 data products, while measurements of parameters related to a-priori data and auxiliary parameters that infuence the quality of the L2 products such as aerosol and cloud profiles and in-situ aerosol and atmospheric chemistry were also collected.