FABIO JULIANO DA SILVA LOPES
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Artigo IPEN-doc 28813 Performance assessment of aerosol-lidar remote sensing skills to retrieve the time evolution of the urban boundary layer height in the Metropolitan Region of São Paulo City, Brazil2022 - MOREIRA, GREGORI de A.; OLIVEIRA, AMAURI P. de; SANCHEZ, MACIEL P.; CODATO, GEORGIA; LOPES, FABIO J. da S.; LANDULFO, EDUARDO; MARQUES FILHO, EDSON P.This paper investigates the performance of seven methods of retrieving the planetary boundary layer height (PBLH) from lidar measurements carried out in the Metropolitan Region of S˜ao Paulo (MRSP) during two MCITY-BRAZIL field campaigns of 2013. The performance is objectively assessed considering as reference the PBLH retrieved from rawinsonde carried out every 3 h during these campaigns. The role of clouds and aerosol load in the performance of the seven methods is analysed considering three case study scenarios representative of typical atmospheric conditions in the MRSP: (a) winter clean atmosphere, (b) summer low clouds and aerosol multilayers, (c) summer sea-breeze intrusion. Corroborating the case study results, the objective analysis indicated that most of the lidar methods retrieved PBLH closer to the top of the entrainment zone than the mixed layer, contradicting their definition. During daytime, the Wavelet Covariance Transform Method performs better than all the other six methods. The Inflexion Point Method performed better to estimate the Residual Layer height during night-time. In average, the diurnal evolution of the PBLH and its local rate of change based on lidar and rawinsonde measurements are in agreement.Artigo IPEN-doc 22641 Diversity on subtropical and polar properties as derived from both ground-based lidars and CALIPSO/CALIOP measurements2017 - CORDOBA JABONERO, CARMEN; LOPES, FABIO J.S.; LANDULFO, EDUARDO; CUEVAS, EMILIO; OCHOA, HECTOR; GIL-OJEDA, MANUELCirrus (Ci) cloud properties can change significantly from place to place over the globe as a result ofweather processes, reflecting their likely different radiative and climate implications. In this work Cirrus clouds (Ci) features observed in late autumn/earlywinter season at both subtropical and polar latitudes are examined and compared to CALIPSO/CALIOP observations. Lidar measurementswere carried out in three stations: São Paulo (MSP, Brazil) and Tenerife (SCO, Canary Islands, Spain), as subtropical sites, and the polar Belgrano II base (BEL, Argentina) in the Antarctic continent. The backscattering ratio (BSR) profiles and the top and base heights of the Ci layers together to their Cirrus Cloud Optical Depth (CCOD) and Lidar Ratio (LR) for Ci clouds were derived. In addition, temperatures at the top and base boundaries of the Ci clouds were also obtained from local radiosoundings to verify pure ice Ci clouds occurrence using a given temperature top threshold (b−38 °C). Ci clouds observed along the day were assembled in groups based on their predominant CCOD, and classified according to four CCOD-based categories. Ci clouds were found to be vertically-distributed in relation with the temperature, forming subvisual Ci clouds at lower temperatures and higher altitudes than other Ci categories at both latitudes. Discrepancies shown on LR values for the three stations, but mainly remarked between subtropical and polar cases, can be associated to different temperature regimes for Ci formation, influencing the internal ice habits of the Ci clouds, and hence likely affecting the LR derived for the Ci layer. In comparison with literature values, daily mean CCOD/LR for SCO (0.4 ± 0.4/21 ± 10 sr), MSP (0.5 ± 0.5/27 ± 5 sr) and BEL (0.2 ± 0.3/28 ± 9 sr) are in good agreement; however, the variability of the Ci optical features along the day present large discrepancies. In comparisonwith CALIOP data, Ci clouds are observed at similar altitudes (around 10–13kmheight); however, differences are found mostly in CCOD values for subtropical Ci clouds, whereas LR values are in a closer agreement. These differences are carefully examined in relation with the closest CALIPSO overpass time and distance from the station (N70 km far), inferring the irregular extension and inhomogeneity of the Ci clouds over each study area. These considerations can be useful for assimilation of the Ci features into climate models and evaluation of future space-borne lidar observations of Ci clouds, especially for the future ESA/Copernicus-Sentinel and ESA/EarthCARE missions.Artigo IPEN-doc 15785 Assessment of biomass burnings activity with the synergy of sunphotometric and LIDAR measurements in Sao Paulo, Brazil2010 - MARIANO, G.L.; LOPES, F.J.S.; JORGE, M.P.P.M.; LANDULFO, E.In the period of July–November of 2007 an aerosol profiling campaign was carried out with a backscattering LIDAR system in São Paulo, Brazil (23° 33′S, 46° 44′W). The goals of this campaign were to perform an aerosol long period observation in the lower atmosphere (up to 10 km) and extract correlations among the microphysical properties obtained from different plataforms, as well to pinpoint events where strong indications of biomass burning plumes werepresent abovetheplanetary boundarylayer (PBL) andstill impact quality reports emitted by ground stations provided by the local environmental agency. In this context the present study aims to investigate the impact that this type of aerosol has on the environment of São Paulo when active fires in South America are observed in close and remote areas. Besides the LIDAR system, an AERONET Sunphotometer was used to help in characterizing the aerosol optical properties. Ten cases were selected as an identification of biomass burning layer entrance and after they were confirmed by NOAA-12 AVHRR sensor and 5-day Hysplit generated backtrajectories. A statistical analysis was carried out for analysis of the extinctionto-backscattering ratio (LIDAR ratio — LR) together with the sunphotometer retrieved Angström Exponent (AE) and aerosol optical depth (AOD) data. The observed layer sources were potentially from remote regions as the South Amazon basin and the north portion of Argentina and closer parts of São Paulo state related to sugar cane harvesting activities. The biomass burning plume heights were between 3 and 8 km. It has been found that LR, AE and AODvalues ranged from 44 to147 sr, from 0.85 to 1.58 and from 0.14 to 0.53, respectively. In a case study for September 7, 2007, an air mass with influence of biomass burning reached the city of São Paulo leading to a LR of 59 sr. Despite the AOD value of 0.33, the aerosol size distribution analysis showed a higher amount of fine particulate matter in relation to coarse that is an indicative of transport of material in the free atmosphere. The analysis carried out in this study shows that these plumes affect greatly the LR mean values while with low effect on the AOD and AE daily averages.