Aplicação dos Modelos de Interação Atmosférica e de Incêndio Florestal BRAMS-SFIRE no sul de Portugal

Resumo O BRAMS-SFIRE é um novo sistema de modelação atmosférica com componente de propagação de fogo desenvolvido no Centro de Previsão de Tempo e Estudos Climáticos (CPTEC / INPE) no Brasil em colaboração com o Instituto Mediterrâneo de Agricultura, Ambiente e Desenvolvimento (MED) em Portugal. O presente artigo descreve a incorporação do modelo de propagação de fogo no Brazilian developments on the Regional Atmospheric Modeling System (BRAMS). Os principais objetivos foram desenvolver o acoplamento entre um modelo atmosférico e um modelo de propagação de fogo que simulasse os efeitos da circulação atmosférica sobre um incêndio florestal e vice-versa. Esta ferramenta tem como objetivo ajudar a entender as relações entre o fogo e a paisagem nas florestas de carvalho mediterrâneas, e avaliar os resultados das simulações deste acoplamento na escala fina no ecossistema do Montado na região do Alentejo. Para isso, três grades de alta resolução espacial ao longo de três incêndios foram configuradas com dados de caracterização de superfície realistas e propriedades dos modelos de combustível. Uma grade foi colocada sobre fogo em uma planície e as outras nas montanhas, para avaliar os diferentes tipos de propagação do fogo. Este trabalho demonstra que este sistema simula de forma consistente a interação entre o fogo, os modelos de combustível e a atmosfera, mostrando que o fogo altera a circulação local ao nível da superfície, intensifica as correntes de vento ascendentes e descendentes, alterando a estrutura da atmosfera.

Application of Kalman Filter and Breeding Ensemble Technique to Forecast the Tropical Cyclone Activity

Tropical cyclone (TC) is one of the major meteorology disasters, as they lead to deaths, destroy the infrastructure and the environment. Therefore, how to improve the predictability of TC’s activities, such as formation, track, and intensity, is very important and is considered an important task for current operational predicting TC centers in many countries. However, predicting TC’s activities has remained a big challenge for meteorologists due to our incomplete understanding of the multiscale interaction of TCs with the ambient environment and the limitation of numerical weather forecast tools. Hence, this chapter will exhibit some techniques to improve the ability to predict the formation and track of TCs using an ensemble prediction system. Particularly, the Local Ensemble Transform Kalman Filter (LETKF) scheme and its implementation in the WRF Model, as well as the Vortex tracking method that has been applied for the forecast of TCs formation, will be presented in subSection 1. Application of Breeding Ensemble to Tropical Cyclone Track Forecasts using the Regional Atmospheric Modeling System (RAMS) model will be introduced in subSection 2.

Numerical Study of Meteorological Factors for Tropospheric Nocturnal Ozone Increase in the Metropolitan Area of São Paulo

One of the central problems in large cities is air pollution, mainly caused by vehicular emissions. Tropospheric ozone is an atmospheric oxidizing gas that forms in minimal amounts naturally, affecting peoples’ health. This pollutant is formed by the NO2 photolysis, creating a main peak during the day. Nighttime secondary peaks occur in several parts of the world, but their intensity and frequency depend on the local condition. In this sense, this works aims to study the local characteristics for tropospheric nocturnal ozone levels in the Metropolitan Area of São Paulo, in Brazil, using the Simple Photochemical Module coupled to the Brazilian Developments on the Regional Atmospheric Modeling System. For this, three different situations of nocturnal occurrence were studied. The results show that the nocturnal maximum of ozone concentrations is related to the vertical transport of this pollutant from higher levels of the atmosphere to the surface and is not related to the synoptic condition.

PREVISÃO DE NEVOEIRO PARA O AEROPORTO DE MACEIÓ USANDO O MODELO BRAMS

Nos aeroportos, eventos de nevoeiro podem causar prejuízos socioeconômicos durante o pouso ou decolagem. Para o Aeroporto Internacional Zumbi dos Palmares foi criada uma ferramenta para a previsão de visibilidade baixa pelo laboratório de Meteorologia Sinótica e Física da Universidade Federal de Alagoas, o Fog VISibility Version 1 (FogVISv1.0). O presente estudo visa, portanto, através dos dados de previsão do modelo de mesoescala Brazilian developments on the Regional Atmospheric Modeling System (BRAMS) simular a visibilidade horizontal através do conteúdo de água líquida (LWC) e a concentração do número de gotas (N​d)​ para seis episódios de nevoeiro ocorridos no Aeroporto Internacional Zumbi dos Palmares entre 2008 a 2014, com duração igual ou superior a 1 hora, com o objetivo de analizar a capacidade da ferramenta FogVISv1.0 tendo como condições iniciais dados do modelo BRAMS, na detecção da visibilidade baixa associada a eventos de nevoeiro. Resultados prévios, obtidos no presente trabalho, ilustram que a ferramenta conseguiu detectar visibilidade baixa em 87% dos eventos de nevoeiro registrados pela estação de superfície do aeroporto, o que totaliza cinco dos seis casos avaliados.

Effects of Aerosols as Ice Nuclei on the Dynamics, Microphysics and Precipitation of Severe Storm Clouds

The Regional Atmospheric Modeling System (RAMS) is used to investigate the effect of aerosols acting as ice nuclei (IN) on the formation and growth of hydrometeor particles as well as on the dynamics and precipitation of a severe storm in Northern China. The focus of this study is to determine how the overall dynamics and microphysical structure of deep convective clouds are influenced if IN concentrations are somehow altered in a storm environment that is otherwise unchanged. Ice mixing ratios tend to increase and liquid mixing ratios tend to decrease with increasing IN concentrations. High concentrations of IN reduce the mean hail diameter and hail particles with smaller diameters melt more easily, which leads to a decrease in ground hailfall and an increase in surface rainfall. Liquid water plays a more important role in the process of hail formation, while the role of ice particles in the process of hail formation decreases with higher IN concentrations. The role of small cloud droplets in the formation of raindrops is increased and the role of hail melting in the process of raindrops formation is weakened with enhanced IN concentrations. Both latent heat release and absorption significantly increase with increasing IN concentrations. Increasing the concentration of IN by an appropriate amount is beneficial for increasing the total water content and strengthening the updraft, leading to enhancement of a storm, but excessive IN concentrations will inhibit the development of a storm.

The Mars Regional Atmospheric Modeling System (MRAMS): Current Status and Future Directions

The Mars Regional Atmospheric Modeling System (MRAMS) is closing in on two decades of use as a tool to investigate mesoscale and microscale circulations and dynamics in the atmosphere of Mars. Over this period of time, there have been numerous improvements and additions to the model dynamical core, physical parameterizations, and framework. At the same time, the application of the model to Mars (and related code for other planets) has taught many lessons about limitations and cautions that should be exercised. The current state of MRAMS is described along with a review of prior studies and findings utilizing the model. Where appropriate, lessons learned are provided to help guide future users and aid in the design and interpretation of numerical experiments. The paper concludes with a discussion of future MRAMS development plans.