Fire hazard forecast by the regional climate change projection using the ETA model: a case study in Bahia, Brazil

This article proposes a method for predicting fire occurrence, considering regional climate change projection using the Eta model, with a 20 km resolution, for the RCP4.5 and RCP8.5 scenarios. Fire occurrence in the state of Bahia was calculated as a function of the three main sensitivity factors on a daily time-scale: days without precipitation, precipitation, and maximum temperature. Historical fire occurrences from 1998 to 2018 and meteorological data from 1960 to 2018 were obtained from official institutes, and weather forecast parameters from 2018 to 2050 were downscaled from the web platform PROJETA. The correlations between the meteorological factors and fire occurrence were calculated for the historical data and a weight factor corresponding to a control simulation. Afterwards, a correction factor was determined, based on the historical fire occurrence data used for the forecast in the two scenarios. The results indicate that between 2018 and 2050, risk of fire will have an average increase of 27% at the RCP4.5 and 38% at the RCP8.5 scenario.

Correlação linear entre a precipitação e o Índice de Área Foliar do bioma Caatinga

Sabe-se que a precipitação é uma variável de difícil estimativa em especial nas regiões semiáridas. Mesmo com os diversos estudos e avanços já obtidos ainda se necessita desenvolver modelos que possam proporcionar estimativas mais reais. Com o intuito de contribuir nessa linha de pesquisa, este estudo teve como objetivo avaliar a relação existente entre a precipitação e o índice de área foliar no bioma caatinga. Para tanto se faz necessário uma boa distribuição espacial da precipitação uma vez que com o uso do sensoriamento remoto é possível obter uma boa estimativa de índice de área foliar espacialmente. Os dados de precipitação utilizados neste estudo foram obtidos pelo o modelo ETA. Os dados de índice de área foliar foram obtidos pelo o sensor MODIS. Utilizou-se o método de correção linear simples. As relações estatísticas mostraram uma boa correlação entre o índice de área foliar e a precipitação. Assim, conclui-se que o entendimento da dinâmica do índice de área foliar espacial e temporal pode ajudar no entendimento da dinâmica espacial e temporal da precipitação na caatinga. Acredita-se que a estimativa da precipitação pelo modelo ETA pode ser melhorada com o uso do índice de área foliar.Palavras-chave: sensoriamento remoto, LAI, modelo ETA, precipitação, caatinga. Linear correlation between rainfall and Leaf Area Index of the Caatinga biome A B S T R A C TIt is known that rainfall is a variable that is difficult to estimate, especially in semiarid regions. Even with the various studies and advances already obtained, it is still necessary to develop models that can provide more real estimates. In order to contribute to this line of research, this study aimed to assess the relationship between rainfall and the leaf area index in the caatinga biome. Therefore, a good spatial distribution of precipitation is necessary since with the use of remote sensing it is possible to obtain a good estimate of the spatial leaf area index. The precipitation data used in this study were obtained using the ETA model. The leaf area index data were obtained by the MODIS sensor. The simple linear correction method was used. The statistical relationships showed a good correlation between the leaf area index and precipitation. Thus, it is concluded that understanding the dynamics of the spatial and temporal leaf area index can help in understanding the spatial and temporal dynamics of precipitation in the caatinga. It is believed that the precipitation estimate by the ETA model can be improved with the use of the leaf area index.Keywords: remote sensing, LAI, ETA model, rainfall, caatinga.

Foehn-like Wind in the Mountains of Southeastern Brazil as Seen by the Eta Model Simulation

The present study gives evidence of the occurrence of foehn-like wind on the eastern slopes of the mountains at Southeastern Brazil. A particular case was detected based on observational evidence on 4 July 2015 near the city of Cruzeiro, state of Sao Paulo, on the Serra da Mantiqueira mountains. Results obtained from numerical simulations are consistent with the foehn wind occurrence deducted from the analysis of regional patterns and time series of selected meteorological parameters.

Projeções da temperatura da superfície na bacia hidrográfica do rio Tietê – SP para o final do Século XXI

A bacia hidrográfica do rio Tietê tem sido afetada por mudanças em seu uso e cobertura do solo, principalmente às margens do rio Tietê, que influenciam diretamente a temperatura da superfície (Ts). Nesse contexto, o objetivo do trabalho é caracterizar sazonalmente a Ts na referida bacia e apresentar projeções dessa variável obtidas com o modelo ETA em alta resolução (5 km) nos cenários RCP4.5 e RCP8.5 e considerando 3 intervalos temporais: 2006-2040, 2040-2070, 2070-2100. Até o final do século XXI algumas áreas da bacia do rio Tietê, bem como sua região de foz, poderão apresentar aumento de até 5º C (8º C) no período entre 2070 - 2100 do cenário RCP4.5 (8.5), o que pode impactar tanto as atividades econômicas quanto o cotidiano da população. Projections of surface temperature in the hydrographic basin of the Tietê river - SP for the end of the 21st century A B S T R A C TThe hydrographic basin of the Tietê river has been affected by changes in its use and land cover, mainly on its banks, which directly influence the surface temperature (Ts). In this context, the objective of the work is to seasonally characterize the Ts in the referred basin and present projections of this variable obtained with the ETA model in high resolution (5 km), under the scenarios RCP4.5 and RCP8.5, and considering 3-time slices: 2006-2040, 2040-2070, 2070-2100. Some calculations (such as climatological averages and bias) were necessary to understand the magnitude of the changes that have occurred and those that may occur. By the end of the 21st century, some areas of the Tietê river basin, as well as its mouth region, may show an increase of up to 5º C (8º C) in the period between 2070 - 2100 of the RCP4.5 (8.5) scenario, which may impact both economic activities and the daily lives of the population.Keywords: Climate Change; Hydrographic Basin; Sao Paulo

In-Vitro Experimental Modeling of Oscillatory Respiratory Flow in a CT-Scanned OSAHS Tract

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a highly prevalent respiratory disorder. The knowledge of respiratory flow is an essential prerequisite for the establishment and development of OSAHS physiology, pathology, and clinical medicine. We made the first in-vitro experimental attempt to measure the oscillatory flow velocity in a computed tomography (CT) scanned extra-thoracic airway (ETA) model with OSAHS by using the particle image velocimetry (PIV) technique. In order to mimic respiration flow, three techniques were adopted to address difficulties in in-vitro experimental modeling: (1) fabricating the obstructive ETA measurement section with the CT-scanned data of an OSAHS patient airway; (2) maintaining the measurement accuracy by using the optical index-matching technique; (3) reproducing the oscillatory respiratory flow rates with the compiled clinical data of transient tidal volumes. The in-vitro measurements of oscillatory respiratory flow velocity manifested the time evolution of the complex OSAHS flow patterns, and the potential wall collapse of the ETA model with OSAHS.

Future scenarios (2011-2040) of temporal and spatial changes in precipitation in the Paraitinga and Paraibuna watersheds, São Paulo, Brazil

The alteration of global climate regimes due to anthropic action and excessive emission of greenhouse gases has been widely researched because it alters the patterns of climatological normals, generating changes in temperatures and precipitation worldwide. This study aimed to analyze the spatial and temporal variability of precipitation in the Paraitinga and Paraibuna watersheds that together form the Paraibuna Dam, the main one of the Paraiba do Sul river watershed. This dam supplies the São Paulo Metropolitan Region by transporting water to the Cantareira System, the Rio de Janeiro Metropolitan Region by transporting water to the Guandu watershed, and the Paraiba Valley Metropolitan Region, one of the most industrialized in Brazil. To investigate future precipitation trends, past and future climate simulations were used from the HadCM3/Eta model using the SRES (Special Report Emission Scenarios) A1B, and precipitation analysis using Quantis techniques to determine extreme rainfall and drought periods. The results point to an increase in precipitation averages in the region, followed by a greater intensity of extreme rainfall, which may lead to a higher occurrence of natural disasters such as landslides.

Estimativa de cheias em bacias hidrográficas com base em previsões de precipitação por conjunto

Bacias hidrográficas são normalmente suscetíveis a inundações devido à associação de fatores ambientais, climáticos e antrópicos. Dentre os métodos utilizados para mitigar os prejuízos provocados por inundações, o sistema de alerta contra cheias pode ser considerado como um dos mais efetivos, devido ao custo relativamente baixo. Neste contexto, o presente trabalho apresenta a avaliação de um modelo de previsão de vazão para os municípios de inseridos na bacia do rio Sapucaí, localizada na região sul do Estado de Minas Gerais. Para isso, é realizada a integração entre o modelo hidrológico MGB-IPH e o modelo atmosférico Eta. São utilizadas previsões de precipitação por conjunto do modelo Eta, que são assimiladas pelo modelo MGB-IPH para gerar previsões de vazão com antecedência de até 5 dias. Os resultados mostram que é possível obter previsões úteis para sistemas e alerta com até 3 dias de antecedência e os melhores resultados são para bacias com maior área de drenagem. Estimation of floods in river basins based on ensemble precipitation forecasts A B S T R A C TWatersheds are normally susceptible to flooding due to the association of environmental, climatic and anthropogenic factors. Among the methods used to mitigate damage caused by floods, the flood warning system can be considered one of the most effective because of the relatively low cost. In this context, the present work presents the evaluation of a flow forecasting model for the municipalities of the Sapucaí river basin, located in the southern region of the State of Minas Gerais. For this, the integration between the hydrological model MGB-IPH and the atmospheric model Eta. Ensemble precipitation forecasts of Eta model are used, which are assimilated by the MGB-IPH model to generate flow forecasts up to 5 days in advance. The results show that it is possible to obtain useful predictions for systems and alerts up to 3 days in advance and the best results are for basins with greater drainage area.

Scenarios from the Eta Model on quality and hydrological quantity in the Atlantic Forest, Southern Brazil

ABSTRACT This work evaluated the response of two scenarios (4.5 and 8.5) of the Eta Model on the quality (sediment - TSS, nitrate - NO3- and phosphate - PO43-) and quantity (flow - Q) of the Concordia Catchment in the Atlantic forest biome. The importance of the work lies in the comparison of both scenarios until 2099, using current agricultural practices (2016). The SWAT model normally used for hydrological purposes has been applied to evaluate water quality from the monitoring programme database (2010-2014). Q showed a non-accentuated, upward trend. Modifications in Q were transmitted to TSS and PO43-. There was no significant difference between the tested scenarios.