IZABEL DA SILVA ANDRADE

IZABEL DA SILVA ANDRADE

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Comparison of PBL heights from ceilometer measurements and greenhouse gases concentrations in São Paulo
2023 - SANTOS, AMANDA V. dos; ARAUJO, ELAINE C.; ANDRADE, IZABEL da S.; CORREA, THAIS; MARQUES, MARCIA T.A.; SOUTO-OLIVEIRA, CARLOS E.; LEONARDO, NOELE F.; MACEDO, FERNANDA de M.; SOUZA, GIOVANNI; LOPES, PEROLA P. de Q.; MOREIRA, GREGORI de A.; ANDRADE, MARIA de F.; LANDULFO, EDUARDO
This paper presents a study conducted in São Paulo, Brazil, where the planetary boundary layer height (PBLH) was determined using ceilometer data and the wavelet covariance transform method. The retrieved PBLH values were subsequently compared with the concentrations of CO2 and CH4 measured at three distinct experimental sites in the city. The period of study was July 2021. This study also included a comparison between ceilometer data and lidar data, which demonstrated the favorable applicability of the ceilometer data for PBLH estimation. An examination of the correlation between changes in average CO2 concentrations and PBLH values revealed stronger correlations for the IAG and UNICID stations, with correlation coefficients (ρ) of approximately −0.86 and −0.85, respectively, in contrast to the Pico do Jaraguá station, which exhibited a lower correlation coefficient of −0.42. When assessing changes in CH4 concentrations against variations in PBL height, the retrieved correlation coefficients were approximately −0.78 for IAG, −0.66 for UNICID, and −0.38 for Pico do Jaraguá. The results indicated that CO2/CH4 concentrations are negatively correlated with PBL heights, with CO2 concentrations showing more significant correlation than CH4 . Additionally, among the three measurement stations, IAG measurements displayed the most substantial correlation. The results from this study contribute to the understanding of the relationship between PBLH and greenhouse gas concentrations, emphasizing the potential of remote sensing systems like ceilometers in monitoring and studying atmospheric processes.
Analyzing the influence of vehicular traffic on the concentration of pollutants in the city of São Paulo
2023 - MOREIRA, GREGORI de A.; CACHEFFO, ALEXANDRE; ANDRADE, IZABEL da S.; LOPES, FABIO JULIANO da S.; GOMES, ANTONIO A.; LANDULFO, EDUARDO
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.
Spatial-temporal analysis of NO2 in the Metropolitan Region of São Paulo
2021 - ANDRADE, IZABEL da S.; ARAUJO, ELAINE C.; CORREA, THAIS; MACEDO, FERNANDA de M; LANDULFO, EDUARDO
Nowadays, several methods of monitoring air pollutants exist, however few allow a large spatial and temporal coverage. Sentinel-5P is a satellite dedicated to atmospheric monitoring with a high spatial-temporal resolution, offering a large data of miscellaneous chemical species. Nitrogen oxides (NO and NO2), emitted by anthropogenic activities into the atmosphere - in large urban centers their main emitting source is vehicles - need particular attention, , in addition to being primary pollutants, they are precursors for formation of other chemical species due to photochemical reactions, mainly tropospheric ozone. These photochemical interactions of NOX stimulate to reduce its lifetime in the atmosphere. Furthermore, these pollutants are used as air quality indexes. The Metropolitan Region of São Paulo (MRSP) has more than 30 cities, being an important economic center for the state of São Paulo. The MRSP has highways with high circulation of light and heavy vehicles, industries and also a high population density. Such factors make this region a favorable area for a satellite study. Thus, the present work uses Sentinel-5P NO2 L2 data in order to analyze the evolution of concentrations throughout 2019.
Methane determination in São Paulo coastal regions using the Cavity Ring-Down Spectroscopy (CRDS) technique
2021 - CORREA, THAIS; MACEDO, FERNANDA M.; ARAUJO, ELAINE C.; ANDRADE, IZABEL S.; GOMES, ANTONIO A.; SILVA, JONATAN; LANDULFO, EDUARDO
Methane is one of the main greenhouse gases due to its high radiation absorption capacity. The increase in methane emissions from anthropogenic sources causes concern in the entire scientific community due to the aggregated uncertainties, generating several works focused on the identification and quantification of generating sources. This work aims to quantify methane in two distinct regions, the first study region is in Cubatão city, located in the São Paulo coast. It is an important petrochemical complex with high industrial activities and environmental impact, presenting 25 large companies in the chemical sector, distributed in an area of 143 Km2. Another region observed is Intanhaém, on the coast of the state of São Paulo. This region doesn´t present industrial activity and has a low population index. The technique used to detect methane in the atmosphere was Cavity ring-down spectroscopy (CRDS), which consists on analysis of atmospheric components, in a small cavity that has a laser and high reflectivity mirrors of 99.999%, allowing the signal travel for kilometers inside the cavity, in a short time, increasing the sensitivity of detection of compounds in the sample.
Preliminary study of greenhouse gases in the Santos Basin
2021 - ARAUJO, ELAINE C.; ANDRADE, IZABEL da S.; MACEDO, FERNANDA de M.; CORREA, THAIS; LANDULFO, EDUARDO
The production of oil and gas onshore and offshore are associated with significant emissions of greenhouse gases, as the entire production chain of oil exploration is a potential source of emission of these gases, especially CH4, which is in almost all stages of the process However, few data is available on emissions from oil exploration platforms in Brazil, despite the increase in oil production on the Brazilian coast since 2008 with the implementation of the Pre-Salt program, which aims to explore oil in the pre-salt layer. Between the explored areas is the Santos Basin which occupies about 350,000 km2 and is located in the southeast region of the Brazilian continental margin, approximately 290 km off the coast of Rio de Janeiro and encompasses the coastlines of the States of Rio de Janeiro, São Paulo , Paraná and Santa Catarina, with boundaries to the north with the Campos Basin by the Alto de Cabo Frio and to the south by the Pelotas Basin by the Florianópolis Platform. Better understanding the ocean-atmosphere interactions in the Santos Basin region, specifically in the coastal area of São Paulo, a temporal analysis was performed using data from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument, which provides data on active burning and from Sentinel-5P (Sentinel 5 Precursor satellite) which brings information from several chemical species, such as NO2 and CH4.
Photochemical sensitivity to emissions and local meteorology in Bogotá, Santiago, and São Paulo
2022 - SEGUEL, RODRIGO J.; GALLARDO, LAURA; OSSES, MAURICIO; ROJAS, NESTOR Y.; NOGUEIRA, THIAGO; MENARES, CAMILO; ANDRADE, MARIA de F.; BELALCAZAR, LUIS C.; CARRASCO, PAULA; ESKES, HENK; FLEMING, ZOE L.; HUNEEUS, NICOLAS; IBARRA-ESPINOSA, SERGIO; LANDULFO, EDUARDO; LEIVA, MANUEL; MANGONES, SONIA C.; MORAIS, FERNANDO G.; MOREIRA, GREGORI A.; PANTOJA, NICOLAS; PARRAGUEZ, SANTIAGO; ROJAS, JHOJAN P.; RONDANELLI, ROBERTO; ANDRADE, IZABEL da S.; TORO, RICHARD; YOSHIDA, ALEXANDRE C.
This study delves into the photochemical atmospheric changes reported globally during the pandemic by analyzing the change in emissions from mobile sources and the contribution of local meteorology to ozone (O3) and particle formation in Bogotá (Colombia), Santiago (Chile), and São Paulo (Brazil). The impact of mobility reductions (50%–80%) produced by the early coronavirus-imposed lockdown was assessed through high-resolution vehicular emission inventories, surface measurements, aerosol optical depth and size, and satellite observations of tropospheric nitrogen dioxide (NO2) columns. A generalized additive model (GAM) technique was also used to separate the local meteorology and urban patterns from other drivers relevant for O3 and NO2 formation. Volatile organic compounds, nitrogen oxides (NOx), and fine particulate matter (PM2.5) decreased significantly due to motorized trip reductions. In situ nitrogen oxide median surface mixing ratios declined by 70%, 67%, and 67% in Bogotá, Santiago, and São Paulo, respectively. NO2 column medians from satellite observations decreased by 40%, 35%, and 47%, respectively, which was consistent with the changes in mobility and surface mixing ratio reductions of 34%, 25%, and 34%. However, the ambient NO2 to NOx ratio increased, denoting a shift of the O3 formation regime that led to a 51%, 36%, and 30% increase in the median O3 surface mixing ratios in the 3 respective cities. O3 showed high sensitivity to slight temperature changes during the pandemic lockdown period analyzed. However, the GAM results indicate that O3 increases were mainly caused by emission changes. The lockdown led to an increase in the median of the maximum daily 8-h average O3 of between 56% and 90% in these cities.
Methane detection in the lower troposphere related to the burning of biomass and leakage in a petrochemical pole, using Raman lidar technique
2021 - MACEDO, FERNANDA de M.; CORREA, THAIS; ARAUJO, ELAINE C.; ANDRADE, IZABEL da S.; GUARDANI, ROBERTO; VESELOVSKII, IGOR; LANDULFO, EDUARDO
Fugitive emissions, defined as unintended or irregular leaks of gases and vapors, are an important source of pollutants to the atmosphere, which is difficult to monitor and control. These sources are present in different sites, especially in regions that are growing in size and economic activity. In this study, we present the results of the capability to detect methane profiles at low troposphere combining data retrieval correlations between a rotacional/vibracional Raman lidar (RVRL) and a cavity ring-down spectrometer (CRDS). The measurements were made at two different sites, metropolitan area of São Paulo (MSP) and industrial area of Cubatão (IC). The lidar is based on a tripled Nd:YAG laser with a 20 Hz repetition rate, operating on the 355 nm wavelength elastic channel, the 353 nm and 396 nm wavelength inelastic channels. A measurement protocol was established, considering acquisition time for signal accumulation, climatic conditions and data above and below the planetary boundary layer. The idea was to establish specific measurement procedures for situations related to product leakage in the oil process and natural events, such as biomass burning. With over 150 hours of data acquisition, the results pointed the possibility of analyzing data from distances up to 1500 m with an initial resolution of 7.5 m which was extended to 100 - 300 m after data smoothing for obtaining final results. The concentration was calculated from the ratio between the methane Raman backscatter signal and the nitrogen signal, at 396 nm and 353 nm, respectively. The temporal variation of methane concentrations was correlated with CRDS data, in order to obtain a first degree calibration.
Analysis of the dispersion of aerosol in Cubatão-SP using remote sensing techniques
2019 - ANDRADE, I. da S.; LANDULFO, E.; ARAUJO, E.C.; MENDONCA, F. de M.; SALANI, M.H.G. de A.; CORREA, T.; MARQUES, M.T.; COSTA, R.F. da; GUARDANI, R.
Aerosls are emitted by a several sources, these can be antropogenic – emitted by human activities - or natural.Their sudies are an important, because its impacts on the dynamics of the Earth’s atmosphere are huge. The study area have one of the most important industrial complex in the state of Sao Paulo. In the past the city of Cubatão was known as “death valey”, due to the environmental problems caused by the high levels of pollutants that was emitted by the industries. Following this event, regulatory laws on atmospheric emissions were developed, both at the state and federal levels. Today, although Cubatão has lower levels of pollution and controlled industrial emissions, but it is possible to observe overcoming air quality standards. Based on the presented context, the present work aims to conduct a study of the dispersion of aerosols in the region of Cubatão-SP using several techniques, such as: remote sensing (elastic lidar and wind lidar), satellite data, air quality information and also simulations of air masses using a model.
COVID-19 outbreak and air quality
2021 - MOREIRA, GREGORI de A.; ANDRADE, IZABEL da S.; CACHEFFO, ALEXANDRE; YOSHIDA, ALEXANDRE C.; GOMES, ANTONIO A.; SILVA, JONATAN J. da; LOPES, FABIO J. da S.; LANDULFO, EDUARDO
This work compares variations in the concentrations and air quality indexes of the pollutants PM10, PM2.5, CO, and NO2, during the COVID-19 outbreak in São Paulo Municipality. Such comparisons considered the period of physical distancing (autumn) and the three first months of economic activities’ resumption (winter). The concentrations and indexes observed in 2020 were compared with their correspondent values measured in the three preceding years. Also, from a supervised machine learning algorithm, the correspondent 2020 expected values were predicted and used in these comparisons. In order to analyze the influence of meteorological conditions, the seasons studied were characterized using remote sensing and surface data. The pollutants predominantly emitted by the vehicle fleet (CO and NO2) had reductions in their concentrations, with values always below the predictions and good air quality indexes. However, the pollutants whose concentration is less dependent on automotive emissions (PM10 and PM2.5) had high proximity to the predictions during the autumn and lower values during some periods in winter. This reduction was not enough to avoid days with a moderate air quality index. The approximation of the average concentrations of PM10, PM2.5, and CO to the prediction, from the second-half August 2020, indicates the influence of activities’ resumption in air quality.
Influence of a biomass-burning event in PM2.5 concentration and air quality
2021 - MOREIRA, GREGORI de A.; ANDRADE, IZABEL da S.; CACHEFFO, ALEXANDRE; LOPES, FABIO J. da S.; YOSHIDA, ALEXANDRE C.; GOMES, ANTONIO A.; SILVA, JONATAN J. da; LANDULFO, EDUARDO
Severe biomass burning (BB) events have become increasingly common in South America in the last few years, mainly due to the high number of wildfires observed recently. Such incidents can negatively influence the air quality index associated with PM2.5 (particulate matter, which is harmful to human health). A study performed in the Metropolitan Area of São Paulo (MASP) took place on selected days of July 2019, evaluated the influence of a BB event on air quality. Use of combined remote sensing, a surface monitoring system and data modeling and enabled detection of the BB plume arrival (light detection and ranging (lidar) ratio of (50 ± 34) sr at 532 nm, and (72 ± 45) sr at 355 nm) and how it affected the Ångström exponent (>1.3), atmospheric optical depth (>0.7), PM2.5 concentrations (>25 µg.m−3), and air quality classification. The utilization of high-order statistical moments, obtained from elastic lidar, provided a new way to observe the entrainment process, allowing understanding of how a decoupled aerosol layer influences the local urban area. This new novel approach enables a lidar system to obtain the same results as a more complex set of instruments and verify how BB events contribute from air masses aloft towards near ground ones.