1
capítulo de libro
Publicado 2020
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Los problemas más graves de contaminación del aire empezaron a ocurrir asociada a la “revolución industrial” iniciada en el siglo XVIII en Inglaterra. Los eventos de contaminación del aire están condicionados por el comportamiento de las variables meteorológicas. Muchos eventos ocurridos y organizados a nivel mundial sirvieron para que se empiece a normar y establecer límites en los niveles de contaminación del aire. El congreso de los EEUU aprobó el acta de Aire Limpio en 1963. El monitoreo del estado del aire o calidad del aire en Perú la empezó el Ministerio de Salud (MINSA) aproximadamente en los años 90 a través de la Dirección General de Salud Ambiental (DIGESA). En el año 2008, el SENAMHI a través de la Dirección General de Investigación y Asuntos Ambientales (DGIA) elaboró un proyecto denominado “Implementación de un Servicio de Pronóstico de Calidad de...
2
artículo
Publicado 2022
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La presente investigación tuvo como objetivo evaluar el desempeño del modelo de Redes Neuronales Artificiales (RNA) para pronosticar las concentraciones de PM10 en el aire, para lo cual se hizo un caso estudio para el distrito de Ate, Lima. Para ello se desarrolló distintas arquitecturas de RNA usando como datos de entrada a los registros de contaminantes del aire y variables meteorológicas obtenidas de la Estación de Monitoreo de la Calidad del Aire “ATE” y datos simulados del modelo WRF-CHEM. Las diferentes arquitecturas de RNA pasaron por un proceso de entrenamiento y verificación, y su desempeño se evaluó mediante el Error Cuadrático Medio (ECM), la precisión (BIAS) y el coeficiente de determinación (R2). Se determinó que la arquitectura que tiene un mejor desempeño tuvo 19 neuronas en la capa oculta, con valores de 0,0230 para el ECM, 0,5308 para la BIAS y 0,823 par...
3
artículo
Publicado 2021
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The sanitary measures implemented to control and prevent an increase in infections due to the COVID-19 pandemic have produced an improvement in the air quality of many urban areas around the world. We assessed air quality during the COVID-19 pandemic for particulate matter (PM2.5 and PM10), NO2 and O3 in in metropolitan area of Lima, Peru between pre-lockdown period (February 1 and March 15 of 2020), historical period (March 16 to April 30 2017–2019) and lockdown period (March 16 to April 30, 2020). The complete national lockdown that was implemented in Peru produced statistically significant reductions in the in-air pollutant (PM10 (-40% and -58%), PM2.5 (-31% and -43%) and NO2 (-46% and -48%)), as recorded by the by the ground-based air quality monitoring network throughout the metropolitan area, compared with the corresponding concentrations for the previous weeks and over the same ...
4
artículo
Publicado 2022
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La presente investigación tuvo como objetivo evaluar el desempeño del modelo de Redes Neuronales Artificiales (RNA) para pronosticar las concentraciones de PM10 en el aire, para lo cual se hizo un caso estudio para el distrito de Ate, Lima. Para ello se desarrolló distintas arquitecturas de RNA usando como datos de entrada a los registros de contaminantes del aire y variables meteorológicas obtenidas de la Estación de Monitoreo de la Calidad del Aire “ATE” y datos simulados del modelo WRF-CHEM. Las diferentes arquitecturas de RNA pasaron por un proceso de entrenamiento y verificación, y su desempeño se evaluó medianteel Error Cuadrático Medio (ECM), la precisión (BIAS) y el coeficiente de determinación (R2). Se determinó que la arquitectura que tiene un mejor desempeño tuvo 19 neuronas en la capa oculta, con valores de 0,0230 para el ECM, 0,5308 para la BIAS y 0,823 para...
5
artículo
Publicado 2018
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This study analyzes ozone formation in the metropolitan area of Lima-Callao as a function of meteorological patterns and the concentrations of nitrogen oxides and reactive organic gases. The study area is located on the west coast of South America (12°S) in an upwelling region that is markedly affected by the Southeast Pacific anticyclone. The vertical stability and diurnal evolution of the mixing layer were analyzed from radiosondes launched daily during 1992–2014 and from two intensive campaigns in 2009. Vertical profiles show that during June–November, the subsidence inversion base ranges from 0.6 to 0.9 km above sea level (asl). In contrast, during December–May, subsidence inversion dissipates, leading to weak surface inversions from 0.1 to 0.6 km asl. At the surface level, compliance with the ozone standard of 51 parts per billion by volume (ppbv) is explained by the marine b...
6
artículo
Publicado 2017
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The temporal and spatial trends in the variability of PM10 and PM2.5 from 2010 to 2015 in the metropolitan area of Lima-Callao, Peru, are studied and interpreted in this work. The mean annual concentrations of PM10 and PM2.5 have ranges (averages) of 133–45 μg m−3 (84 μg m−3) and 35–16 μg m−3 (26 μg m−3) for the monitoring sites under study. In general, the highest annual concentrations are observed in the eastern part of the city, which is a result of the pattern of persistent local winds entering from the coast in a south-southwest direction. Seasonal fluctuations in the particulate matter (PM) concentrations are observed; these can be explained by subsidence thermal inversion. There is also a daytime pattern that corresponds to the peak traffic of a total of 9 million trips a day. The PM2.5 value is approximately 40% of the PM10 value. This proportion can be explained ...
7
artículo
Publicado 2020
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This study evaluates the concentration of PM10 and PM2.5 andidentifies the sources of pollution in the districts of San Juan de Lurigancho (SJL) and Puente Piedra (PPD) located in the eastern and northern zones of the Metropolitan area of Lima,Peru. The samples were collected between April and May 2017 by the National Meteorology and Hydrology Service of Peru (SENAMHI). The concentrations of PM10 and PM2.5, measured using gravimetric techniques, exceeded the international (WHO) and national reference values; with maximum values for PM10 and PM2.5 of 160 and 121.56 µg/ m3 in PPD and 295.06 and 154.58 µg/ m3 in SJL respectively. Pollution sources were identified using the Positive Matrix Factorization Model (PMF 5.0) and Principal Component Analysis (PCA), and showed similar sources for both districts. In SJL, sources were determined to be a combination of vehicular traffic and the resus...
8
artículo
Publicado 2021
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Background: Coronavirus disease 2019 (COVID-19) originated in the People’s Republic of China in December 2019. Thereafter, a global logarithmic expansion of cases occurred. Some countries have a higher rate of infections despite the early implementation of quarantine. Air pollution might be related to high susceptibility to the virus and associated case fatality rates (deaths/cases*100). Lima, Peru, has the second highest incidence of COVID-19 in Latin America and also has one the highest levels of air pollution in the region. Methods: This study investigated the association of levels of PM2.5 exposure in previous years (2010–2016) in 24 districts of Lima with cases, deaths and case fatality rates for COVID-19. Multiple linear regression was used to evaluate this association controlled by age, sex, population density and number of food markets per district. The study period was from ...
9
documento de trabajo
Publicado 2020
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Until June 12, 2020, there were 6,308 deaths and 220,749 SARS-CoV-2 positive cases in Peru. In Lima, the total number of COVID-19 deaths in all metropolitan areas was 2,382. The case-fatality rate at the national level was 2.58% and 1.93% in Lima. Higher PM2.5 levels are associated with higher number of cases and deaths of COVID-19. The case-fatality rate (Deaths/cases*100) did not increase with the increase in PM2.5 levels. A higher number of food markets was associated with higher incidence and mortality of COVID-19 (p < 0.01 for both); these associations persisted when cases (r = 0.49; p < 0.01) and deaths (r = 0.58; p < 0.01) were adjusted by the population density. The association of PM2.5 with cases of COVID-19 was maintained after controlling analysis by age, sex and number of food markers.
10
artículo
Publicado 2023
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The need to generate objective evidence and reliable information for decision makers to improve environmental policies for a better air quality, led us to evaluate the atmospheric aerosol components in the urban area of Carabayllo, by monitoring PM2.5 and PM10 to determine mass concentration and analyzing PM10 using k0-INAA and ICP–MS for metals quantification, ion chromatography for anions and the NIOSH method to determine organic and elemental carbon. The results obtained from mass concentration of PM2.5 and PM10 exceeded the permissible breathing annual average of WHO guidelines of 15 µgm−3 and 45 µgm−3, respectively, which evidence an unhealthy air quality. Likewise, using the model Positive Matrix Factorization five sources of pollutants were defined: metallurgical industry, sea salt, industrial activity, dust and non-exhaust emissions and vehicle emissions.
11
artículo
Publicado 2021
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We present the effects of the confinement and physical distancing policies applied during the COVID-19 pandemic on the concentrations of PM10, PM2.5, NO, NO2 and O3 in 16 cities in central and southern Chile. The period between March and May in 2020 was compared with the corresponding months during 2017–2019, using surface data and satellite information. The relative percent changes in the concentration of atmospheric pollutants, and the meteorological variables observed between these two periods were used to quantify the effects of the lockdowns on the local air quality of the urban areas studied. The results showed statistically significant changes in 11 of the 16 cities. Significant relative changes between +14% and –33% were observed for PM10 in 9 cities; while statistically significant changes between –6% and –48% were evident for PM2.5 in 10 cities. Significant decreases be...
12
artículo
Publicado 2021
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The implementation of confinement and physical distancing measures to restrict people's activities and transit in the midst of the COVID-19 pandemic allowed us to study how these measures affect the air quality in urban areas with high pollution rates, such as Santiago, Chile. A comparative study between the concentrations of PM10, PM2.5, NOx, CO, and O3 during the months of March to May 2020 and the corresponding concentrations during the same period in 2017–2019 is presented. A combination of surface measurements from the air quality monitoring network of the city, remote satellite measurements, and simulations of traffic activity and road transport emissions allowed us to quantify the change in the average concentrations of each pollutant. Average relative changes of traffic emissions (between 61% and 68%) implied statistically significant concentrations reductions of 54%, 13%, and ...
13
artículo
Publicado 2022
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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 reduc...
14
artículo
Publicado 2021
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This global study, which has been coordinated by the World Meteorological Organization Global Atmospheric Watch (WMO/GAW) programme, aims to understand the behaviour of key air pollutant species during the COVID-19 pandemic period of exceptionally low emissions across the globe. We investigated the effects of the differences in both emissions and regional and local meteorology in 2020 compared with the period 2015–2019. By adopting a globally consistent approach, this comprehensive observational analysis focuses on changes in air quality in and around cities across the globe for the following air pollutants PM2.5, PM10, PMC (coarse fraction of PM), NO2, SO2, NOx, CO, O3 and the total gaseous oxidant (OX = NO2 + O3) during the pre-lockdown, partial lockdown, full lockdown and two relaxation periods spanning from January to September 2020. The analysis is based on in situ ground-based ai...
