O estudo avaliou o desempenho das estimativas do produto CHIRPS em caracterizar as chuvas nos municípios de São Gonçalo e Niterói, no Rio de Janeiro, em comparação com dados observados in situ de 14 anos (2005-2018). Foram utilizados os indicadores estatísticos: coeficiente de correlação de Pearson (r), coeficiente de determinação (R²), raiz do erro médio quadrático (RMSE, mm) e BIAS (%). Os resultados mostraram que o produto CHIRPS obteve desempenho satisfatório. Em três dos cinco pluviômetros analisados, a correlação (r) foi superior a 0,80 e o coeficiente (R²) superior a 0,64. Nos outros pluviômetros, a correlação foi um pouco mais baixa, com (r) acima de 0,71 e (R²) em torno de 0,50. O BIAS indicou superestimativa do CHIRPS, geralmente abaixo de 20%, e o RMSE mostrou que nas estimativas do CHIRPS ocorreram menores erros, próximo de 30 (mm). De forma geral, a distribuição anual das chuvas variou entre 850 e 1550 (mm), com maior registro no setor Norte (N) de Niterói, nas direções Sul/Sudeste de São Gonçalo. Conclui-se que o produto CHIRPS foi eficaz em fornecer estimativas precisas e capazes de caracterizar a variação espaço-temporal da precipitação nos municípios avaliados.

Three cumulus and five microphysics parameterization schemes of the Weather Research and Forecasting model (WRF) are the basis for simulating ten specific meteorological events of the Paraíba do Sul River Basin (PSRB) in Southeast Brazil. The cases studied are frontal wave systems, thermodynamic instability, and the South Atlantic Convergence Zone (SACZ). Each parameterization combination generated 15 simulations for each event, resulting in 150 tests. The primary domain has a horizontal resolution of 8.0 km and the nested 2.6 km resolution. Three analysis tools underlie the study: (i) punctual verification of the first 24 h of precipitation forecast, using the Taylor diagram; (ii) verification of the prediction of precipitation using categorical binary variable and (iii) the Model´s ability to reproduce patterns of the spatial distribution of precipitation. The Taylor diagram suggests that the combination of the Morrison Double moment and Multiscale Kain–Fritsch schemes produce the best results. The categorical verification indicates that, for dynamic/convective events, the Morrison Double moment and Multiscale Kain–Fritsch and WRF Double Moment 6–class sets showed the best indices. Some configurations presented reliable results for exclusively convective events, and WRF Single–moment 6–class and Grell–Freitas Ensemble is the best combination. The Morrison Double moment and Multiscale Kain–Fritsch parameterizations yielded the best performance for the spatial distribution. Overall, the schemes tested perform better for the upstream region, i.e., the area of greater water uptake for the basin.

Eventos extremos de chuva e cidades não planejadas reforçam a importância do mapeamento das inundações urbanas. Por outro lado, dados espaciais e meteorológicos disponibilizados por agências governamentais, não são compatíveis com o estudo de inundações e assim criam um cenário escasso de dados efetivamente medidos. Dessa forma, o presente trabalho objetiva mapear o perigo de inundações para bacia hidrográfica urbana (Rio Botas, Nova Iguaçu, Rio de Janeiro) com poucos dados disponíveis. O mapeamento é realizado por meio de modelos hidrológico e hidrodinâmico. Como a referida bacia não possui estação pluviométrica com série histórica robusta é implementada uma metodologia para selecionar uma estação representativa no seu entorno, sendo essa a estação meteorológica Ecologia Agrícola. O regime de chuva encontrado no estudo é compatível com os cenários de alerta da Defesa Civil, o que sugere que a metodologia é válida, nesse caso. Com relação às modelagens, independente da ausência de dados mais específicos o resultado foi considerado satisfatório, pois na validação empírica os pontos alagados foram os mesmos apresentados pelos agentes da Defesa Civil. Sendo assim, os resultados obtidos demonstram que é possível realizar um mapeamento de inundação satisfatório mesmo em bacias hidrográficas com escassez de dados.

The waters of the Paraíba do Sul River supply around 15 million people, most of whom live in metropolitan regions of the state of Rio de Janeiro. Climate change alters its precipitation regime and can cause an increase in the occurrence of extreme hydrological events. Furthermore, the variability of precipitation can result from the combined effects of the surface conditions of the oceans and the variations in the dynamics of atmospheric systems. This work aims to detect possible changes in the climatic extremes of precipitation in the Paraíba do Sul hydrographic basin and to investigate evidences of correlation of these indices with the oceanic oscillations associated with the El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO) and Atlantic Multidecadal Oscillation (AMO). Results indicate that the northeast sector of the basin present trends of increase in the total annual precipitation, in the number of very humid days and in the occurrence of extreme events, in a space of time up to five days. The southwest sector, on the other hand, show decreasing trends in total annual precipitation, in the number of very humid days, but with an increase trend in the maximum amount of rainfall on five consecutive days. The central sector has characteristics of a transition zone. The correlation analyzes show that oceanic oscillation indices have a non-significant correlation with most annual extreme precipitation indices, except for La Niña (El Niño), that can increase (decrease) the number of consecutive dry days in the region. Besides, for austral autumn, La Niña (El Niño) can decrease (increase) the precipitation in the basin, and in austral winter, hot (cold) phase of AMO can decrease (increase) the precipitation. For austral spring, two teleconnections were found: hot (cold) phase of PDO can increase (decrease) the precipitation in the southwest region of the basin, and during El Niño (La Niña) years, negative (positive) precipitation anomalies tend to occur in the northeast sector of the basin, while positive (negative) anomalies appear in its southwest region. The wavelet spectrum of precipitation anomaly indicates significant values with low power that could be correlated with ENSO, corroborating the results of seasonal correlations.

Abstract The waters of the Paraíba do Sul River supply around 15 million people, most of whom live in metropolitan regions of the state of Rio de Janeiro. Climate change alters its precipitation regime and can cause an increase in the occurrence of extreme hydrological events. The variability of precipitation results from the combined effects of the surface conditions of the oceans and the variations in the dynamics of atmospheric systems. This work aims to detect possible changes in the climatic extremes of precipitation in the Paraíba do Sul hydrographic basin and to investigate evidences of correlation of these indices with the oceanic oscillations associated with the El Niño-Southern Oscillation, Pacific Decadal Oscillation, North Atlantic Oscillation and Atlantic Multidecadal Oscillation. Results indicate that the eastern and northeastern sectors of the basin present trends of increase in the total annual precipitation, in the number of very humid days and in the occurrence of extreme events, in a space of time up to five days. The west and southwest sectors, on the other hand, show decreasing trends in total annual precipitation, in the number of very humid days, but with an increase trend in the maximum amount of rainfall on five consecutive days. The central sector has characteristics of a transition zone. The correlation analyzes show that the majority of the oceanic oscillation indices have a very weak correlation with the extreme precipitation indices, while the wavelet transform does not indicate significant power at the low frequencies.

O estudo da distribuição de chuva no Brasil é importante tanto para a economia quanto para a redução de desastres naturais. Os eventos de chuvas intensas que causam tanto secas quanto inundações geram perdas e danos sobretudo para a população mais carente. Com isso, o objetivo deste artigo é analisar a distribuição espaço temporal das chuvas na região da Baixada Fluminense, Rio de Janeiro, no período entre 2003 e 2017. Para o estudo foram utilizados seis postos pluviométricos e estações meteorológicas, distribuídas ao longo da região. A chuva anual acumulada para a Baixada Fluminense é de 1830 mm, com os meses de maio a setembro sendo os mais chuvosos, com destaque para janeiro com 269 mm. O período seco da região é de abril a outubro com a menor média em agosto com 64mm. Um fator importante é a distribuição espacial da chuva, onde a região leste da Baixada Fluminense apresenta os maiores valores de chuva, principalmente, em Duque de Caxias e Guapimirim. A região Oeste é a menos chuvosa com destaque para Piraí e Seropédica. Esta distribuição desigual da chuva indica a influência do fator topográfico na espacialização da chuva na Baixada Fluminense, como as baías da Guanabara e Sepetiba que são fontes de umidade. Além da Serra do Mar e do Morro da Mazomba que são bloqueios orográficos frente às massas de ar.

Extreme events affect societies all around the world. A recent example is the submarine volcano Hunga Tonga-Hunga Ha'apai in the South Pacific Ocean, which erupted on January 15, 2022 at approximately 0415 UTC, expelling ash up to 39 kilometers high. Instruments around the world recorded both the initial atmospheric shock wave and the subsequent tsunami signal. The aim of this work is to report the record from tide gauges and barometers of this event along the Brazilian coast. For this, the tsunami travel time to Brazil was calculated, and spikes in atmospheric pressure data and noise in the tide gauge records were identified. The arrival of the tsunami waves was clearly observed in tidal records from three stations located in Imbituba, Arraial do Cabo, and Salvador. In addition, in Belém and Santana, the signal-to-noise ratio was too low or there was no signal at all. Surprisingly, the atmospheric signal was less observable. The shock wave signature was evident in the Fortaleza atmospheric pressure data, while at the Imbituba and Belém stations the signal only appeared after filtering the data by calculating the highest and lowest pressure difference within the hour. The weaker, or absence of, barometric signal is likely associated with the supposed attenuation, or blocking, of the signal by the Andes Mountains.

This work aims to identify, by means of statistical analysis, the relationship between extreme precipitation events and SST anomalies (SSTA) in the municipalities surrounding the Ilha Grande (IGB) and Sepetiba (SB) bays in the state of Rio de Janeiro evaluating its annual distributions using measured data from rainfall stations and relating these events to potential SST anomalies found in this region. Data from 10 rainfall stations distributed around the bays and SST dataset obtained from the Multi-scale Ultra-high Resolution Sea Surface Temperature (MUR) from 2003 to 2014 were used. SSTA and their average were generated for each of the three subareas delimited in the study area. The obtained time series of each subarea define the thresholds for significant SSTA, based on their respective standard deviation. The number of days with SSTA were obtained from these significant anomaly values, and days with positive or negative SSTA, for each subarea, were computed. For SSTA analysis, only events with significant anomalies were considered. Only SSTA occurring on the days of intense precipitation highlighted in P95 and up to 3 days before the extreme event date were analyzed. The results had shown that about 35% of extreme precipitation events were potentially related to the presence of significant SST anomalies in the studied area. Finally, it is pointed that regional anomalies in SST, such as those described in this study, can also contribute to the formation of extreme rain events.

O Complexo Lagunar da Baixada de Jacarepaguá (CLBJ), situado ao sul do município do Rio de Janeiro formado por 5 lagunas costeiras, apresenta um sistema estuarino complexo e altamente produtivo, que sustenta uma rica biodiversidade de plantas aquáticas e animais. O acelerado processo de urbanização ao seu entorno, tem acarretado um intenso processo de eutrofização e assoreamento desses corpos d’água, e que precisa ser melhor compreendido. Assim, o presente trabalho teve como objetivo calcular o tempo de residência (TR) das águas do Complexo através da utilização de um modelo numérico computacional, o MOHID - Water Modelling System. Inicialmente foram feitos testes para se avaliar as respostas do modelo frente os diferentes forçantes, introduzindo primeiramente apenas a maré e posteriormente a descarga dos rios e o regime de vento local. O estudo do TR das águas do complexo foi feito pela implementação do modelo hidrodinâmico acoplado ao modelo de transporte lagrangeano. O cenário construído para simulação considerou os principais forçantes que regem a hidrodinâmica do sistema, maré, descarga dos principais tributários e regime de vento local (hipotético). Os resultados de elevação de nível d’água e circulação obtidos se mostraram bem satisfatórios, com grande semelhança aos dados coletados em campo e com estudos pretéritos. Revelando um alto TR, atingindo uma taxa de renovação máxima de apenas 23% durante o período de 30 dias de simulação, o Canal da Joatinga e a Lagoa de Camorim foram as áreas que apresentaram menor TR, de 7 dias e 12 dias, respectivamente, para uma taxa de renovação de aproximadamente 92%. Para as demais regiões, durante todo o período da simulação, valores de taxa de renovação que variaram entre 59% para Lagoa da Tijuca a 0% para a Lagoa de Marapendi. O regime de troca hídrica das regiões próximas a desembocadura do CLBJ é controlado pelo regime de maré enquanto as regiões mais interiores possuem maior influência dos agentes continentais.

Fogs are meteorological events in which water vapor condensation in the atmosphere results in a horizontal visibility inferior to 1000 m, making air, sea and land traffic difficult. Fogs are classified according to their formation processes and require the presence of specific initial conditions, such as elevated humidity, thermal inversion and atmospheric stability. In general, when atmospheric temperature and dew point temperature are equal, there is fog formation. This can occur due to either atmospheric cooling or increase in atmospheric humidity. The objective of this study is to examine the meteorological conditions in Rio de Janeiro Harbor by analyzing the occurrence of fog, as well as observations of meta-oceanographic conditions associated with fog formation processes. Thirteen years of METAR data from surface meteorological stations located in Santos Dumont and Galeão airports were studied. The results revealed a strong seasonality of fog occurrence, showing a higher occurrence during autumn and winter. It was also observed that there is a relationship between the interannual variability and ENSO cycles and a strong fog event dependence on meteorological conditions such as atmospheric pressure and relative humidity

This work presents the results of a photochemical modelling system composed of MM5-SMOKE-CMAQ on Brazilian Amazonia area, been a pioneered implementation task. These results focus on the biogenic and biomass burning emissions and the impact of these emissions on regional air quality. Global and local anthropogenic emissions data, satellite-derived biomass burning inventories, and biogenic emissions calculated with MEGAN model were used to estimate emissions over the domain. The goal is the development of air quality model input data for CMAQ. Results are consistent with O-3 formation theory and CO hotspot concentration matches with the geographic area of biomass burning.

Urban-scale air quality modeling over Brazil has been advancing in recent years with several modelin g studies of air quality in the metropolitan areas of Rio de Janeiro and Sao Paulo especially. Extending these photochemical modeling applications to the continental scale in order to study regional transport of pollutants throughout South America is the focus of this prese ntation. This work presents the initial results of a photochemical modeling system composed f MM5-SMOKE-CMAQ that focuses on the Amazonia reg ion of Brazil. These results focus on biogenic and biomass burning emiss ion in Amazonia and the impact of these emissions on regional and local air quality. A combination of global and local anthropogenic emiss ions data, satellite-derived biomass burning invent ories, and biogenic emissions calculated with the MEGAN model were used to estima te emissions over the mother domain at grid resolut ion of 37-km. The mother domain covers most of South America. We modeled August 200 5 because it was the driest period in the region ov er the last 50 years. Due to a lack of surface-based air quality monitoring data in Ama zonia, we are exploring model evaluation techniques sing satellite-based air quality products. This paper focuses on the development of the input data to the CMAQ air quality model, inclu ding initial and boundary conditions, meteorology, and emissions. Preliminary CMAQ result s are also presented along with qualitative compari sons against satellite networks for some air pollutants. Results are consistent with th eory of O3 formation and were compared with MODIS TERRA satel lite data available.

This work presents the implementation of a low cost computing system for the forecast of the atmospheric pollutant dispersion generated in petroleum platforms in Campos Basin - RJ. A mesoscale meteorological model was used to complement the necessary meteorological database for the use of the dispersion model. To this meteorological model, a series of statistical tests were applied seeking to compare the behavior of the model face to the monitored data available. The results indicated that the meteorological model represented satisfactorily the wind field on the area and that the values foreseen for the concentration of pollutant SO2 were always below the effective patterns however, they indicated that there is transport of pollutant from producing units to the continent.