Navegação Periódicos - Artigos por Autores IPEN "LANDULFO, EDUARDO"

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  • IPEN-DOC 27704

    OLIVEIRA, DANIEL C.F. dos S.; MONTILLA-ROSERO, ELENA; LOPES, FABIO J. da S. ; MORAIS, FERNANDO G. ; LANDULFO, EDUARDO ; HOELZEMANN, JUDITH J.. Aerosol properties in the atmosphere of Natal/Brazil measured by an AERONET Sun-photometer. Environmental Science and Pollution Research, v. 28, n. 8, p. 9806-9823, 2021. DOI: 10.1007/s11356-020-11373-z

    Abstract: We analyzed data measured by a Sun-photometer of the RIMA-AERONET network with the purpose to characterize the aerosol properties in the atmosphere over Natal, state capital of Rio Grande do Norte, at the coast of Northeast Brazil. Aerosol Optical Depth, Ångström Exponent, Volume Size Distribution, Single Scattering Albedo, Complex Refractive Index, Asymmetry Factor, and Precipitable Water were analyzed from August 2017 to March 2018. In addition, MODIS and CALIOP observations, local Lidar measurements, and modeled backward trajectories were analyzed in a case study on February 9, 2018, that consistently confirmed the identification of a persistent aerosol layer below 4 km agl. Aerosols present in the atmosphere of Natal showed monthly mean Aerosol Optical Depth at 500 nm below 0.15 (~ 75%), monthly means of the Ångström Exponent at 440–670 nm between 0.30 and 0.70 (~ 69%), bimodal Volume Size Distribution is dominantly coarse mode, Single Scattering Albedo at 440 nm is 0.80, Refractive Index - Real Part around 1.50, Refractive Index - Imaginary Part ranging from 0.01 to 0.04, and the Asymmetry Factor ranged from 0.73 to 0.80. The aerosol typing during the measurement period showed that atmospheric aerosol over Natal is mostly composed of mixed aerosol (58.10%), marine aerosol (34.80%), mineral dust (6.30%), and biomass burning aerosols (0.80%). Backward trajectories identified that 51% of the analyzed air masses over Natal originated from the African continent.

    Palavras-Chave: satellite atmospheres; sun; photometers; optical radar; optical systems; aerial monitoring; atmospheres; optical properties; dusts; environment; environmental impacts; physical properties; biomass; brazil; africa; climatic change

  • IPEN-DOC 17830

    MARIANO, GLAUBER L.; LOPES, FABIO J.; STEFFENS, JULIANA; MARTIN, MARIA P.P.; LANDULFO, EDUARDO ; HELD, GERHARD; ANJOS, SERGIO dos. Aerosols monitoring in Rio Claro, Brazil: using lidar and air pollution analyzers. Optica Pura y Aplicada, v. 44, n. 1, p. 55-64, 2011.

    Palavras-Chave: brazil; biomass plantations; burns; aerosol monitoring; radar

  • IPEN-DOC 22451

    LANDULFO, EDUARDO ; LOPES, FABIO J. da S. ; MOREIRA, GREGORI de A. ; MARQUES, MARCIA T.A. ; OSNEIDE, MARCELO ; ANTUNA, JUAN C.; ARREDONDO, RENE E.; RASCADO, JUAN L.G.; ALADOS ARBOLEDAS, LUCAS; BASTIDAS, ALVARO; NISPERUZA, DANIEL; BEDOYA, ANDRES; MUNERA, MAURICIO; ALEGRIA, DAIRO; FORNO, RICARDO N.; SANCHEZ, MARIA F.; LAZCANO, OSCAR; MONTILLA ROSERO, ELENA; SILVA, ANTONIETA; JIMENEZ, CRISTOFER; QUEL, EDUARDO; RISTORI, PABLO; OTERO, LIDIA; BARBOSA, HENRIQUE M.J.; GOUVEIA, DIEGO A.; BARJA, BORIS. ALINE/LALINET network status. EPJ Web of Conferences, v. 119, 2016.

    Palavras-Chave: computer networks; optical radar; inventories; monitoring; optical properties; distribution

  • IPEN-DOC 26403

    OLIVEIRA, ALINE M. de; SOUZA, CRISTINA T.; OLIVEIRA, NARA P.M. de; MELO, ALINE K.S.; LOPES, FABIO J.S. ; LANDULFO, EDUARDO ; ELBERN, HENDRIK; HOELZEMANN, JUDITH J.. Analysis of atmospheric aerosol optical properties in the northeast Brazilian atmosphere with remote sensing data from MODIS and CALIOP/CALIPSO satellites, AERONET photometers and a ground-based Lidar. Atmosphere, v. 10, n. 10, p. 1-22, 2019. DOI: 10.3390/atmos10100594

    Abstract: A 12-year analysis, from 2005 to 2016, of atmospheric aerosol optical properties focusing for the first time on Northeast Brazil (NEB) was performed based on four di erent remote sensing datasets: the Moderate Resolution Imaging Spectroradiometer (MODIS), the Aerosol Robotic Network (AERONET), the Cloud-Aerosol LIDAR with Orthogonal Polarization (CALIOP) and a ground-based Lidar from Natal. We evaluated and identified distinct aerosol types, considering Aerosol Optical Depth (AOD) and Angström Exponent (AE). All analyses show that over the NEB, a low aerosol scenario prevails, while there are two distinct seasons of more elevated AOD that occur every year, from August to October and January to March. According to MODIS, AOD values ranges from 0.04 to 0.52 over the region with a mean of 0.20 and occasionally isolated outliers of up to 1.21. Aerosol types were identified as sea spray, biomass burning, and dust aerosols mostly transported from tropical Africa. Three case studies on days with elevated AOD were performed. All cases identified the same aerosol types and modeled HYSPLIT backward trajectories confirmed their source-dependent origins. This analysis is motivated by the implementation of an atmospheric chemistry model with an advanced data assimilation system that will use the observational database over NEB with the model to overcome high uncertainties in the model results induced by still unvalidated emission inventories.

    Palavras-Chave: aerosols; aerosol monitoring; optical radar; dusts; datasets; satellites; atmospherics; meteorology; optical properties; brazil; atmospheric circulation

  • IPEN-DOC 26404

    MOREIRA, GREGORI de A. ; LOPES, FABIO J. da S. ; GUERRERO-RASCADO, JUAN L.; SILVA, JONATAN J. da ; GOMES, ANTONIO A. ; LANDULFO, EDUARDO ; ALADOS-ARBOLEDAS, LUCAS. Analyzing the atmospheric boundary layer using high-order moments obtained from multiwavelength lidar data: impact of wavelength choice. Atmospheric Measurement Techniques, v. 12, n. 8, p. 4261-4276, 2019. DOI: 10.5194/amt-12-4261-2019

    Abstract: The lowest region of the troposphere is a turbulent layer known as the atmospheric boundary layer (ABL) and characterized by high daily variability due to the influence of surface forcings. This is the reason why detecting systems with high spatial and temporal resolution, such as lidar, have been widely applied for researching this region. In this paper, we present a comparative analysis on the use of lidar-backscattered signals at three wavelengths (355, 532 and 1064 nm) to study the ABL by investigating the highorder moments, which give us information about the ABL height (derived by the variance method), aerosol layer movement (skewness) and mixing conditions (kurtosis) at several heights. Previous studies have shown that the 1064 nm wavelength, due to the predominance of particle signature in the total backscattered atmospheric signal and practically null presence of molecular signal (which can represent noise in high-order moments), provides an appropriate description of the turbulence field, and thus in this study it was considered a reference. We analyze two case studies that show us that the backscattered signal at 355 nm, even after applying some corrections, has a limited applicability for turbulence studies using the proposed methodology due to the strong contribution of the molecular signature to the total backscatter signal. This increases the noise associated with the high-order profiles and, consequently, generates misinformation. On the other hand, the information on the turbulence field derived from the backscattered signal at 532 nm is similar to that obtained at 1064 nm due to the appropriate attenuation of the noise, generated by molecular component of backscattered signal by the application of the corrections proposed.

    Palavras-Chave: troposphere; optical radar; boundary layers; atmospheres; aerosols; turbulence; air quality; monitoring

  • IPEN-DOC 29836

    MOREIRA, GREGORI de A. ; CACHEFFO, ALEXANDRE ; ANDRADE, IZABEL da S. ; LOPES, FABIO JULIANO da S. ; GOMES, ANTONIO A. ; LANDULFO, EDUARDO . Analyzing the influence of vehicular traffic on the concentration of pollutants in the city of São Paulo: an approach based on pandemic SARS-CoV-2 data and deep learning. Atmosphere, v. 14, n. 10, p. 1-16, 2023. DOI: 10.3390/atmos14101578

    Abstract: This study employs surface and remote sensing data jointly with deep learning techniques to examine the influence of vehicular traffic in the seasonal patterns of CO, NO2 , PM2.5, and PM10 concentrations in the São Paulo municipality, as the period of physical distancing (March 2020 to December 2021), due to SARS-CoV-2 pandemic and the resumption of activities, made it possible to observe significant variations in the flow of vehicles in the city of São Paulo. Firstly, an analysis of the planetary boundary layer height and ventilation coefficient was performed to identify the seasons’ patterns of pollution dispersion. Then, the variations (from 2018 to 2021) of the seasonal average values of air temperature, relative humidity, precipitation, and thermal inversion occurrence/position were compared to identify possible variations in the patterns of such variables that would justify (or deny) the occurrence of more favorable conditions for pollutants dispersion. However, no significant variations were found. Finally, the seasonal average concentrations of the previously mentioned pollutants were compared from 2018 to 2021, and the daily concentrations observed during the pandemic period were compared with a model based on an artificial neural network. Regarding the concentration of pollutants, the primarily sourced from vehicular traffic (CO and NO2 ) exhibited substantial variations, demonstrating an inverse relationship with the rate of social distancing. In addition, the measured concentrations deviated from the predictive model during periods of significant social isolation. Conversely, pollutants that were not primarily linked to vehicular sources (PM2.5 and PM10) exhibited minimal variation from 2018 to 2021; thus, their measured concentration remained consistent with the prediction model.

    Palavras-Chave: urban areas; air pollution; air quality; machine learning; vehicles; coronaviruses

  • IPEN-DOC 25711

    MOREIRA, GREGORI de A. ; GUERRERO-RASCADO, JUAN L.; BENAVENT-OLTRA, JOSE A.; ORTIZ-AMEZCUA, PABLO; ROMAN, ROBERTO; BEDOYA-VELASQUEZ, ANDRES E.; BRAVO-ARANDA, JUAN A.; REYES, FRANCISCO J.O.; LANDULFO, EDUARDO ; ALADOS-ARBOLEDAS, LUCAS. Analyzing the turbulent planetary boundary layer by remote sensing systems: the Doppler wind lidar, aerosol elastic lidar and microwave radiometer. Atmospheric Chemistry and Physics, v. 19, n. 2, p. 1263-1280, 2019. DOI: 10.5194/acp-19-1263-2019

    Abstract: The planetary boundary layer (PBL) is the lowermost region of troposphere and is endowed with turbulent characteristics, which can have mechanical and/or thermodynamic origins. This behavior gives this layer great importance, mainly in studies about pollutant dispersion and weather forecasting. However, the instruments usually applied in studies of turbulence in the PBL have limitations in spatial resolution (anemometer towers) or temporal resolution (instrumentation aboard an aircraft). Ground-based remote sensing, both active and passive, offers an alternative for studying the PBL. In this study we show the capabilities of combining different remote sensing systems (microwave radiometer – MWR, Doppler lidar – DL – and elastic lidar – EL) for retrieving a detailed picture on the PBL turbulent features. The statistical moments of the high frequency distributions of the vertical wind velocity, derived from DL, and of the backscattered coefficient, derived from EL, are corrected by two methodologies, namely first lag correction and 􀀀2=3 law correction. The corrected profiles, obtained from DL data, present small differences when compared with the uncorrected profiles, showing the low influence of noise and the viability of the proposed methodology. Concerning EL, in addition to analyzing the influence of noise, we explore the use of different wavelengths that usually include EL systems operated in extended networks, like the European Aerosol Research Lidar Network (EARLINET), Latin American Lidar Network (LALINET), NASA Micro-Pulse Lidar Network (MPLNET) or Skyradiometer Network (SKYNET). In this way we want to show the feasibility of extending the capability of existing monitoring networks without strong investments or changes in their measurements protocols. Two case studies were analyzed in detail, one corresponding to a well-defined PBL and another corresponding to a situation with presence of a Saharan dust lofted aerosol layer and clouds. In both cases we discuss results provided by the different instruments showing their complementarity and the precautions to be applied in the data interpretation. Our study shows that the use of EL at 532 nm requires a careful correction of the signal using the first lag time correction in order to get reliable turbulence information on the PBL.

    Palavras-Chave: boundary layers; troposphere; planetary atmospheres; doppler effect; wind; optical radar; monitoring; microwave radiation; radiometers; aerosols; elastic scattering; remote sensing

  • IPEN-DOC 24737

    GOUVEIA, DIEGO; BAARS, HOLGER; SEIFERT, PATRIC; WANDINGER, ULLA; BARBOSA, HENRIQUE; BARJA, BORIS; ARTAXO, PAULO; LOPES, FABIO ; LANDULFO, EDUARDO ; ANSMANN, ALBERT. Application of a multiple scattering model to estimate optical depth, lidar ratio and ice crystal effective radius of cirrus clouds observed with lidar. EPJ Web of Conferences, v. 176, n. 05037, p. 1-4, 2018. DOI: 10.1051/epjconf/201817605037

    Abstract: Lidar measurements of cirrus clouds are highly influenced by multiple scattering (MS). We therefore developed an iterative approach to correct elastic backscatter lidar signals for multiple scattering to obtain best estimates of single-scattering cloud optical depth and lidar ratio as well as of the ice crystal effective radius. The approach is based on the exploration of the effect of MS on the molecular backscatter signal returned from above cloud top.

    Palavras-Chave: multiple scattering; optical radar; crystals; clouds; optical depth curve; elastic scattering; photons

  • IPEN-DOC 15784

    STEFFENS, JULIANA; LANDULFO, EDUARDO ; COURROL, LILIA C. ; GUARDANI, ROBERTO. Application of fluorescence to the study of crude petroleum. Journal of Fluorescence, v. 21, n. 3, p. 859-864, 2011.

    Palavras-Chave: petroleum; fluorescence; emission spectroscopy; oils

  • IPEN-DOC 16003

    AMARAL, MARCELLO M. ; RAELE, MARCUS P. ; LANDULFO, EDUARDO ; VIEIRA JUNIOR, NILSON D. ; FREITAS, ANDERSON Z. . Application of lidar-like equations to OCT signal analysis for total extinction coefficiente determination. Revista Brasileira de Pesquisa e Desenvolvimento, v. 12, n. 1, p. 29-33, 2010.

    Palavras-Chave: tomography; optical systems; coherence length; backscattering; mathematical models; equations; refractive index; animal tissues; diagnosis

  • IPEN-DOC 28812

    MOREIRA, GREGORI de A. ; OLIVEIRA, AMAURI P. de; CODATO, GEORGIA; SANCHEZ, MACIEL P.; TITO, JANET V.; SILVA, LEONARDO A.H. e; SILVEIRA, LUCAS C. da; SILVA, JONATAN J. da ; LOPES, FABIO J. da S. ; LANDULFO, EDUARDO . Assessing spatial variation of PBL height and aerosol layer aloft in São Paulo Megacity using simultaneously two lidar during winter 2019. Atmosphere, v. 13, n. 4, p. 1-16, 2022. DOI: 10.3390/atmos13040611

    Abstract: This work presents the use of two elastic lidar systems to assess the horizontal variation of the PBL height (PBLH) and aerosol layer aloft in the São Paulo Megacity. These two lidars performed simultaneous measurements 10.7 km apart in a highly urbanized and relatively flat area of São Paulo for two winter months of 2019. The results showed that the PBLH differences display diurnal variation that depends on the PBL during daytime growth phases. Cloud and sea breeze effects control most of PBLH variation. In the absence of cloud and sea breeze, the maximum difference (~300 m) occurs in the rapid development stage and is due to topographic effects. When the PBL approaches its maximum daily value, it tends to level off with respect to the topography. In addition, it was presented a method that combines elastic lidar (to detect an aerosol layer) and satellite data (to classify such a layer from Aerosol Optical Depth (AOD) and Aerosol Index (AI) information) for the detection of biomass burning events. This methodology demonstrated that the variations caused by Biomass Burning in AOD and AI enable both the detection of aerosol plumes originating from biomass burning and the identification of their origin.

    Palavras-Chave: boundary layers; earth atmosphere; biomass; burns; urban areas; optical radar

  • IPEN-DOC 13142

    CARRILO, ARTHUR M.; LANDULFO, EDUARDO ; VIEIRA JUNIOR, NILSON D. ; NOGUEIRA, GESSE E.C. ; VIDAL, JOSE T. ; RAFAELLI, JORGE C.; NERES, NILSON L.. Automation of a lidar system using Labview software for unattended measurements and use in a meteorology virtual course. Optica Pura y Aplicada, v. 41, n. 2, p. 97-100, 2008.

    Palavras-Chave: meteorology; optical radar; computer codes; learning

  • IPEN-DOC 27568

    LORIATO, AYRES G.; SALVADOR, NADIR; LORIATO, AYRAN A.B.; NASCIMENTO, ERIC G.S.; MOREIRA, DAVIDSON M.; REIS JUNIOR, NEYVAL C.; SOKOLOV, ANTON; LANDULFO, EDUARDO ; ALBUQUERQUE, TACIANA T. de A.. Brazilian coastal region modeling with WRF/SMOKE/CMAQ and atmospheric parameter measurement validation with radio probing, Sodar and Lidar. International Journal of Research in Engineering and Science, v. 8, n. 12, p. 1-15, 2020.

    Abstract: This article aims to evaluate and compare data of vertical potential temperature profile, wind velocity and PM10 concentration measured during an experimental campaign on July 2012 by means of radio probing, Sonic Detection And Ranging (SODAR) and Light Detection And Ranging (LIDAR) with those modeled by means of numerical simulation with Weather Research And Forecast Model (WRF), Sparse Matrix Operator Kernel Emissions (SMOKE) and Community Multi-Scale Air Quality (CMAQ). The study has been conducted at Região da Grande Vitória (RGV), a Brazilian coastal region. All data measurements have been done at Universidade Federal do Espírito Santo (UFES), in the city of Vitória, Espírito Santo, Brazil. For numerical simulation, RGV's emissions inventory has been used to model a 61x79km2 grid with spatial resolution of 1 km2 and temporal resolution of 1 hour. Sea breeze is a relevant weather phenomenon along coastal regions, and it has been perceived by both SODAR measurement and WRFmodeling. During the experimental campaign, the most intense sea breeze occurred on July 28, 2012 and, therefore, a thorough analysis of atmospheric and pollution parameters has been done for that day. This analysis showed neutral atmosphere up to 200 meters of altitude and stability beyond that, which has been confirmed by WRFmodeling. Regarding wind data, the comparison between SODAR measurement and WRFmodeling showed similarities regarding wind direction, but wind speed was overestimated by WRF. Lastly, LIDAR measurement and CMAQmodeling showed close values for PM10 pollutant concentration.

    Palavras-Chave: coastal regions; air pollution; optical radar; atmospheres; meteorology; air quality

  • IPEN-DOC 17829

    STEFFENS, JULIANA; GUARDANI, ROBERTO; LANDULFO, EDUARDO ; LOPES, FABIO J.S.; MOREIRA JUNIOR, PAULO F.; MOREIRA, ANDREIA. Capability at atmospheric air monitoring in the urban area of Cubatão using Lidar techniques. Optica Pura y Aplicada, v. 44, n. 1, p. 65-70, 2011.

    Palavras-Chave: brazil; atmospheric chemistry; air pollution monitoring; radar; aerosol monitoring

  • IPEN-DOC 29106

    BEU, CASSIA M.L. ; LANDULFO, EDUARDO . Caracterização do perfil vertical do vento em Iperó (São Paulo) com o uso de um lidar doppler / Characterization of the wind vertical profile in Iperó (São Paulo) with the use of a doppler lidar. Revista Brasileira de Climatologia, v. 30, p. 424-444, 2022. DOI: 10.55761/abclima.v30i18.15582

    Abstract: Um lidar Doppler com alcance até 290 m operou continuamente por 1 ano no município de Iperó, interior de São Paulo. O lidar usado possui alta resolução vertical e temporal e estima além da velocidade e direção do vento horizontal, também a velocidade vertical do vento. O banco de dados gerado durante essa campanha experimental permitirá estudar fenômenos da Camada Limite Planetária, bem como validar modelos numéricos e auxiliar estudos de transporte e dispersão de poluentes. Neste trabalho é apresentada a caracterização do perfil vertical do vento e o ciclo anual entre Agosto/2017 e julho/2018.

    Palavras-Chave: atmospheric precipitations; atmospheric circulation; wind; seasons; aerosol monitoring; air samplers; pollution; earth atmosphere

  • IPEN-DOC 29051

    IBARRA-ESPINOSA, SERGIO ; REHBEIN, AMANDA; FREITAS, EDMILSON D. de; MARTINS, LEILA; ANDRADE, MARIA de F.; LANDULFO, EDUARDO . Changes in a bottom-up vehicular emissions inventory and its impact on air pollution during COVID-19 Lockdown in São Paulo, Brazil. Frontiers in Sustainable Cities, v. 4, p. 1-12, 2022. DOI: 10.3389/frsc.2022.883112

    Abstract: Due to coronavirus disease 2019 (COVID-19), many cities implemented strict lockdown to stop the spread of this new disease. Consequently, it was reported lower levels of air pollution due to less human activity outdoors. The changes were registered using surface monitoring stations or satellite observations. However, modeling those environmental changes has remained a challenge because of our limitations in the emissions estimation and also, for the numerical modeling itself. In this study, the vehicular emissions were estimated for March 2020 in the megacity of São Paulo using the Vehicular Emissions INventory model (VEIN). The emissions estimation showed an increment of VOC/NO2 downtown, due to the decrease in circulation of urban transportation and light vehicles. Then, a set of Weather Research and Forecasting models with chemistry (WRF-Chem) simulations were performed with different chemical mechanisms and initial conditions. The modeled diurnal cycles represent the variations observed in March 2020 for the periods pre-lockdown, transition, and lockdown. However, it is imperative to include other sources than vehicular to have a local and comprehensive emissions inventory.

    Palavras-Chave: coronaviruses; emission; air pollution abatement; vehicles; forecasting; meteorology

  • IPEN-DOC 29837

    VIEIRA, ERICK V.R.; ROSARIO, NILTON E. do; YAMASOE, MARCIA A.; MORAIS, FERNANDO G.; MARTINEZ, PEDRO J.P.; LANDULFO, EDUARDO ; MIRANDA, REGINA M. de. Chemical characterization and optical properties of the aerosol in São Paulo, Brazil. Atmosphere, v. 14, n. 9, p. 1-21, 2023. DOI: 10.3390/atmos14091460

    Abstract: : Air pollution in the Metropolitan Area of São Paulo (MASP), Brazil, is a serious problem and is strongly affected by local sources. However, atmosphere column composition in MASP is also affected by biomass burning aerosol (BB). Understanding the impacts of aerosol particles, from both vehicles and BB, on the air quality and climate depends on in-depth research with knowledge of some parameters such as the optical properties of particles and their chemical composition. This study characterized fine particulate matter (PM2.5) from July 2019 to August 2020 in the eastern part of the MASP, relating the chemical composition data obtained at the surface and columnar optical parameters, such as aerosol optical depth (AOD), Ångström Exponent (AE), and single-scattering albedo (SSA). According to the analyzed data, the mean PM2.5 concentration was 18.0 ± 12.5 µg/m3 ; however, daily events exceeded 75 times the air quality standard of the World Health Organization (15 µg/m3 ). The mean black carbon concentration was 1.8 ± 1.5 µg/m3 in the sampling period. Positive matrix factorization (PMF) identified four main sources of aerosol: heavy vehicles (42%), followed by soil dust plus local sources (38.7%), light vehicles (9.9%), and local sources (8.6%). AOD and AE presented the highest values in the dry period, during which biomass burning events are more frequent, suggesting smaller particles in the atmosphere. SSA values at 440 nm were between 0.86 and 0.94, with lower values in the winter months, indicating the presence of more absorbing aerosol.

    Palavras-Chave: particulates; air pollution; air quality; urban areas; aerosols; optical properties

  • IPEN-DOC 29870

    PALLOTTA, JUAN V.; CARVALHO, SILVANIA A. de; LOPES, FABIO J. da S. ; CACHEFFO, ALEXANDRE; LANDULFO, EDUARDO ; BARBOSA, HENRIQUE M.J.. Collaborative development of the Lidar Processing Pipeline (LPP) for retrievals of atmospheric aerosols and clouds. Geoscientific Instrumentation Methods and Data Systems, v. 12, n. 2, p. 171-185, 2023. DOI: 10.5194/gi-12-171-2023

    Abstract: Atmospheric lidars can simultaneously measure clouds and aerosols with high temporal and spatial resolution and hence help understand cloud–aerosol interactions, which are the source of major uncertainties in future climate projections. However, atmospheric lidars are typically custom-built, with significant differences between them. In this sense, lidar networks play a crucial role as they coordinate the efforts of different groups, provide guidelines for quality-assured routine measurements and opportunities for side-by-side instrument comparisons, and enforce algorithm validation, all aiming to homogenize the physical retrievals from heterogeneous instruments in a network. Here we provide a high-level overview of the Lidar Processing Pipeline (LPP), an ongoing, collaborative, and open-source coordinated effort in Latin America. The LPP is a collection of tools with the ultimate goal of handling all the steps of a typical analysis of lidar measurements. The modular and configurable framework is generic enough to be applicable to any lidar instrument. The first publicly released version of the LPP produces data files at levels 0 (raw and metadata), 1 (averaging and layer mask), and 2 (aerosol optical properties). We assess the performance of the LPP through quantitative and qualitative analyses of simulated and measured elastic lidar signals. For noiseless synthetic 532 nm elastic signals with a constant lidar ratio (LR), the root mean square error (RMSE) in aerosol extinction within the boundary layer is about 0.1 %. In contrast, retrievals of aerosol backscatter from noisy elastic signals with a variable LR have an RMSE of 11 %, mostly due to assuming a constant LR in the inversion. The application of the LPP for measurements in São Paulo, further constrained by co-located AERONET data, retrieved a lidar ratio of 69.9 ± 5.2 sr at 532 nm, in agreement with reported values for urban aerosols. Over the Amazon, analysis of a 6 km thick multi-layer cirrus found a cloud optical depth of about 0.46, also in agreement with previous studies. From this exercise, we identify the need for new features and discuss a roadmap to guide future development, accommodating the needs of our community.

  • IPEN-DOC 13031

    WHITERMAN, DAVID N.; VANABLE, DEMETRIUS D.; LANDULFO, EDUARDO . Comments on “Accuracy of Raman lidar water vapor calibration and its applicability to long-term measurements”. Applied Optics, v. 50, n. 15, p. 2170-2176, 2011.

    Palavras-Chave: water vapor; calibration; raman spectroscopy; optical radar; measuring instruments

  • IPEN-DOC 27244

    MOREIRA, GREGORI de A. ; LOPES, FABIO J. da S. ; GUERRERO-RASCADO, JUAN L.; ORTIZ-AMEZCUA, PABLO; CAZORLA, ALBERTO; OLIVEIRA, AMAURI P. de; LANDULFO, EDUARDO ; ALADOS-ARBOLEDAS, LUCAS. Comparison among the atmospheric boundary layer height estimated from three different tracers. EPJ Web of Conferences, v. 237, p. 1-4, 2020. DOI: 10.1051/epjconf/202023703009

    Abstract: The Atmospheric Boundary Layer (ABL) is the lowermost part of the troposphere. In this work, we analysed the combination of ABL height estimated continuously by three different remote sensing systems: a ceilometer, a Doppler lidar and a passive Microwave Radiometer, during a summer campaign, which was held in Granada from June to August 2016. This study demonstrates as the combined utilization of remote sensing systems, based on different tracers, can provide detailed information about the height of ABL and their sublayers.

    Palavras-Chave: atmospheres; doppler effect; boundary layers; troposphere; optical radar; microwave radiation; radiometers

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Para indexação dos documentos é utilizado o Thesaurus do INIS, especializado na área nuclear e utilizado em todos os países membros da International Atomic Energy Agency – IAEA , por esse motivo, utilize os termos de busca de assunto em inglês; isto não exclui a busca livre por palavras, apenas o resultado pode não ser tão relevante ou pertinente.

95% do RD apresenta o texto completo do documento com livre acesso, para aqueles que apresentam o significa que e o documento está sujeito as leis de direitos autorais, solicita-se nesses casos contatar a Biblioteca do IPEN, bibl@ipen.br .

Ao efetuar a busca por um autor o RD apresentará uma relação de todos os trabalhos depositados no RD. No lado direito da tela são apresentados os coautores com o número de trabalhos produzidos em conjunto bem como os assuntos abordados e os respectivos anos de publicação agrupados.

O RD disponibiliza um quadro estatístico de produtividade, onde é possível visualizar o número dos trabalhos agrupados por tipo de coleção, a medida que estão sendo depositados no RD.

Na página inicial nas referências são sinalizados todos os autores IPEN, ao clicar nesse símbolo será aberta uma nova página correspondente à aquele autor – trata-se da página do pesquisador.

Na página do pesquisador, é possível verificar, as variações do nome, a relação de todos os trabalhos com texto completo bem como um quadro resumo numérico; há links para o Currículo Lattes e o Google Acadêmico ( quando esse for informado).

ATENÇÃO!

ESTE TEXTO "AJUDA" ESTÁ SUJEITO A ATUALIZAÇÕES CONSTANTES, A MEDIDA QUE NOVAS FUNCIONALIDADES E RECURSOS DE BUSCA FOREM SENDO DESENVOLVIDOS PELAS EQUIPES DA BIBLIOTECA E DA INFORMÁTICA.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

1. Portaria IPEN-CNEN/SP nº 387, que estabeleceu os princípios que nortearam a criação do RDI, clique aqui.


2. A experiência do Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP) na criação de um Repositório Digital Institucional – RDI, clique aqui.

O Repositório Digital do IPEN é um equipamento institucional de acesso aberto, criado com o objetivo de reunir, preservar, disponibilizar e conferir maior visibilidade à Produção Científica publicada pelo Instituto, desde sua criação em 1956.

Operando, inicialmente como uma base de dados referencial o Repositório foi disponibilizado na atual plataforma, em junho de 2015. No Repositório está disponível o acesso ao conteúdo digital de artigos de periódicos, eventos, nacionais e internacionais, livros, capítulos, dissertações, teses e relatórios técnicos.

A elaboração do projeto do RI do IPEN foi iniciado em novembro de 2013, colocado em operação interna em julho de 2014 e disponibilizado na Internet em junho de 2015. Utiliza o software livre Dspace, desenvolvido pelo Massachusetts Institute of Technology (MIT). Para descrição dos metadados adota o padrão Dublin Core. É compatível com o Protocolo de Arquivos Abertos (OAI) permitindo interoperabilidade com repositórios de âmbito nacional e internacional.

O gerenciamento do Repositório está a cargo da Biblioteca do IPEN. Constam neste RI, até o presente momento 20.950 itens que tanto podem ser artigos de periódicos ou de eventos nacionais e internacionais, dissertações e teses, livros, capítulo de livros e relatórios técnicos. Para participar do RI-IPEN é necessário que pelo menos um dos autores tenha vínculo acadêmico ou funcional com o Instituto. Nesta primeira etapa de funcionamento do RI, a coleta das publicações é realizada periodicamente pela equipe da Biblioteca do IPEN, extraindo os dados das bases internacionais tais como a Web of Science, Scopus, INIS, SciElo além de verificar o Currículo Lattes. O RI-IPEN apresenta também um aspecto inovador no seu funcionamento. Por meio de metadados específicos ele está vinculado ao sistema de gerenciamento das atividades do Plano Diretor anual do IPEN (SIGEPI). Com o objetivo de fornecer dados numéricos para a elaboração dos indicadores da Produção Cientifica Institucional, disponibiliza uma tabela estatística registrando em tempo real a inserção de novos itens. Foi criado um metadado que contém um número único para cada integrante da comunidade científica do IPEN. Esse metadado se transformou em um filtro que ao ser acionado apresenta todos os trabalhos de um determinado autor independente das variáveis na forma de citação do seu nome.