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Extremos de precipitação diária em Belém, Pará, e estrutura vertical da atmosfera; Extreme daily rainfall in Belém, Pará, and vertical structure of atmosphere

Camponogara, Glauber
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 06/03/2012 Português
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36.56%
Diversas atividades ligados ao gerenciamento de recursos hídricos necessitam da previsão de acumulados diários de chuva extremos. Entretanto, grande parte dos modelos utilizados operacionalmente apresentam uma tendência a subestimar os extremos de precipitação mesmo com apenas 24 horas de antecedência. Existem diversas razões para esse tipo de erro de previsão tais como, limitações nas parametrizações de convecção para modelos com resolução de dezenas de quilômetros e a não inclusão do efeito de aerossóis como núcleos de condensação de gotas de nuvens nos modelos de grande escala. Dentro desse contexto, este trabalho tem como objetivo analisar situações de eventos extremos de precipitação na região de Belém, Pará, onde o regime de precipitação é modulado, principalmente, pela brisa marítima, linhas de instabilidade, distúrbios ondulatório de leste, zona de convergência intertropical, alta da Bolívia e Vórtices Ciclônicos de Altos Níveis (VCAN). A abordagem será de identificação de perfis verticais cinemáticos e termodinâmicos típicos de eventos extremos de precipitação diária em Belém, Pará. Para esse fim, escolheu-se fazer uma análise de dados de radiossondagem e precipitação utilizando as Funções Ortogonais Empíricas (EOF - Empirical Orthogonal Functions combinadas e verificar como o Brazilian developments on the Regional Atmospheric Modeling System (BRAMS) simula características básicas de chuva acumulada diária. A variância explicada das EOF calculadas a partir do conjunto de variáveis acumulado diário de precipitação (acpcp)...

Modelagem hidrológica com uso da estimativa de chuva por sensoriamento remoto; Modeling hidrological with use rainfall estimates of remote sensing

Quiroz Jiménez, Karena
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Dissertação Formato: application/pdf
Português
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46.53%
As estimativas de chuva por meio do sensoriamento remoto são, atualmente, fonte potencialmente útil para as mais diversas aplicações hidrológicas e climatológicas, especialmente em regiões onde as medições convencionais são escassas, como a Amazônia. Neste trabalho, foram analisadas as estimativas de chuva por satélite como variáveis de entrada ao modelo hidrológico MGB-IPH (Collischonn, 2001). Este modelo simula o ciclo hidrológico através das relações físicas e conceituais de todo processo, sendo os produtos de chuva por satélite avaliados o 3B42, 3B42RT e CMORPH. A primeira área de estudo é a bacia do rio Huallaga localizada dentro do território do Peru, região caracterizada por ter uma topografia complexa e pertencente a uma das nascentes do rio Amazonas. A segunda avaliação foi feita para a bacia do rio Amazonas, sendo esta caracterizada por ter uma grande variabilidade climatológica a diferentes altitudes e regimes hidrológicos diferentes, além de uma pobre distribuição de postos pluviométricos. No caso da bacia do rio Huallaga foram realizadas comparações da chuva média estimada por satélite com observada em intervalos de tempo diário, mensal, sazonal e anual. Estes resultados mostram que os produtos 3B42 e CMORPH subestimam valores médios da bacia comparada com chuva média ponderada por pluviômetros. Na simulação da bacia do rio Huallaga se efetuaram calibrações dos parâmetros para cada fonte de chuva resultando com melhor ajuste de vazões máximas para o produto CMORPH e pior ajuste para o produto 3B42...

Analise da precipitação pluvial e de veranicos no estado do Rio Grande do Sul por meio de tecnicas de mineração de dados; Analysis of rainfall and dry spells in the state Rio Grande do Sul through data mining techniques

Raquel Stucchi Boschi
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 22/02/2010 Português
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36.4%
No atual cenário de aquecimento global, fenômeno ao qual a ocorrência de secas intensas e eventos extremos de chuva está cada vez mais associada, o conhecimento do comportamento da precipitação pluvial é fundamental para um planejamento agrícola adequado. A imprevisibilidade das variações climáticas e a dependência do regime pluviométrico são os principais fatores de risco e insucesso na produção agrícola. A variabilidade temporal da precipitação é apontada como a principal causa das variações dos rendimentos das principais culturas, particularmente no Rio Grande do Sul. Na Região Sul do Brasil, este é o estado mais afetado pelas secas. Esses períodos de estiagens conhecidos como veranicos, são apontados como um dos principias fatores limitantes da produção agrícola, uma vez que, dependendo da sua duração e frequência, podem provocar reduções significativas na produção final das culturas. O objetivo deste trabalho é analisar o comportamento espaço temporal da precipitação pluvial e dos veranicos no Rio Grande do Sul, por meio da aplicação de técnicas de mineração de dados. As séries históricas deste estudo foram adquiridas junto à Agência Nacional de Água (ANA), disponíveis no sistema de informações hidrológicas Hidroweb (http://hidroweb.ana.gov.br/). A metodologia utilizada teve como base o modelo CRISP-DM (Cross Industry Standard Process for Data Mining). Primeiramente...

Rainfall erosivity and rainfall return period in the experimental watershed of Aracruz, in the coastal plain of Espirito Santo, Brazil

Martins,Sérgio Gualberto; Avanzi,Junior Cesar; Silva,Marx Leandro Naves; Curi,Nilton; Norton,Lloyd Darrell; Fonseca,Sebastião
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2010 Português
Relevância na Pesquisa
36.42%
Knowledge on the factors influencing water erosion is fundamental for the choice of the best land use practices. Rainfall, expressed by rainfall erosivity, is one of the most important factors of water erosion. The objective of this study was to determine rainfall erosivity and the return period of rainfall in the Coastal Plains region, near Aracruz, a town in the state of Espírito Santo, Brazil, based on available data. Rainfall erosivity was calculated based on historic rainfall data, collected from January 1998 to July 2004 at 5 min intervals, by automatic weather stations of the Aracruz Cellulose S.A company. A linear regression with individual rainfall and erosivity data was fit to obtain an equation that allowed data extrapolation to calculate individual erosivity for a 30-year period. Based on this data the annual average rainfall erosivity in Aracruz was 8,536 MJ mm ha-1 h-1 yr-1. Of the total annual rainfall erosivity 85 % was observed in the most critical period October to March. Annual erosive rains accounted for 38 % of the events causing erosion, although the runoff volume represented 88 % of the total. The annual average rainfall erosivity return period was estimated to be 3.4 years.

The Incidence of Norovirus-Associated Gastroenteritis Outbreaks in Victoria, Australia (2002–2007) and Their Relationship with Rainfall

Bruggink, Leesa D.; Marshall, John A.
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
36.37%
The relationship between the incidence of norovirus-associated gastroenteritis outbreaks (NAGOs) in Victoria, Australia for the period 2002–2007 and rainfall was examined. Statistical analysis involving the correlation between time series indicated that there was a statistically significant (p < 0.05) correlation between monthly NAGO incidence and average monthly rainfall. There was a lag of an average of about three months between peak average rainfall and a NAGO epidemic. The findings thus indicate rainfall can influence NAGO incidence. In an era where there is concern about the potential effects of global warming on weather patterns, it should be borne in mind that future changes in NAGO incidence may reflect altered world weather patterns.

An??lise harm??nica dos totais de chuvas mensais de regi??es homog??neas do Estado do Rio Grande do Sul; Harmonic analysis of the total rainfall monthly of homogeneous regions of the state of Rio Grande do Sul

CARDOSO, Daniel Souza
Fonte: Universidade Federal de Pelotas; Meteorologia; Programa de P??s-gradua????o em Meteorologia; UFPel; BR Publicador: Universidade Federal de Pelotas; Meteorologia; Programa de P??s-gradua????o em Meteorologia; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
46.31%
Whereas the State of Rio Grande do Sul (RS), have an economy directly dependent on agriculture and livestock sectors, which in different studies are reported as dependent on the variability of certain climatological elements, and the RS element water is regarded as fundamental. We conducted a study of the monthly total rainfall, to long 60 years (1948/2007), collected from 31 meteorological stations (EMs) and distributed geographically in the state. In the interest of contributing to the local society to predict possible shortages, and / or development of public policies for the use of water resources in urban and rural areas. In order to obtain a model that can provide an approximation of the behavior of the average rainfall for each of the six homogeneous regions, as defined in the literature (Marques, 2005), held has an harmonic analysis of the data previously adjusted to 30-day months. Before the analisys, the properties were checked for normality, homogeneity of variance and stationarity. The data tested for normality and homogeneity of variances, have not passed satisfactory in these tests and, hence, there was a transformation of data, generating new data sets that met the conditions of homogeneity of variance and normality. The relative increase in the trend...

A Variabilidade da precipita????o no Rio Grande do Sul e sua rela????o com o ??ndice de Oscila????o Ant??rtica; Variability of rainfall in Rio Grande do Sul and its relationship with the Antarctic Oscillation Index

GARCIA, Maria Arita Madruga
Fonte: Universidade Federal de Pelotas; Meteorologia; Programa de P??s-gradua????o em Meteorologia; UFPel; BR Publicador: Universidade Federal de Pelotas; Meteorologia; Programa de P??s-gradua????o em Meteorologia; UFPel; BR
Tipo: Dissertação Formato: application/pdf
Português
Relevância na Pesquisa
36.43%
This research aims to analyze the monthly variations of rainfall in Rio Grande do Sul (RS) relating to monthly changes in the average thickness of the troposphere (700mb) at the bottom of the Southern Hemisphere, which is centered in the region of Antarctica. Monthly anomalies of atmospheric thickness have been represented by principal oscillation pattern that is called the Arctic Oscillation Index. This study is important because RS has played an important role in national agricultural production, and the variable rainfall has been identified as a key role in the productivity of different regional cultures. During the study, monthly rainfall data from 32 meteorological stations in RS has been used, which has been correlated with the Arctic Oscillation Index. The Arctic Oscillation Index has been obtained directly from Climate Prediction Center and the study period has been from 1979 to 2008 and, the correlations between the monthly rainfalls have been tested considering the time lags of index 0, -1, -2, -3 months. The results of the climatology have showed that rainfall in these last three decades have presented patterns and distributed monthly throughout the year and lower values to the south and higher to the north and northwest. The largest temporal gradient in RS has occurred between the months of October and November...

Assessment of Rainfall Influence Over Water Quality at the Effluent of an Urban Catchment by High Temporal Resolution Measurements

Sandoval Arenas, Santiago
Fonte: Pontifícia Universidade Javeriana Publicador: Pontifícia Universidade Javeriana
Tipo: masterThesis; Tesis de Grado Maestría Formato: Pdf
Português
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36.47%
#-#Calidad del agua#Maestría en hidrosistemas - Tesis y disertaciones académicas#The present study aimed to establish the rainfall influence over the water quality at the effluent of an urban catchment by the use of temporal high resolution measurements. The water quantity and quality parameters at the effluent of the studied urban catchment (Gibraltar: Bogotá, Colombia) were measured by means of infra-red, ion sensitive, UV-VIS spectrometry (water quality) and ultrasonic (water quantity: flow rate) sensors. Hence, the rainfall pulses were registered at three rain gauge stations (Fontibon, Bosa and Casablanca) in proximities of the studied urban catchment. A methodology for identifying periods in which water quality and quantity seemed to be ranging outside of their typical dry weather behavior was designed, by the use of signal processing and time series techniques (Median Filter, Step Detection and Autocorrelation functions-ACF-). A Principal Components Analysis (PCA) brought up a preliminary insight of which water quality and quantity parameters seem to explain mostly the differences between the variability of dry and wet weather data. The most explicative parameters measured by means of uni-parametric and ultrasonic sensors were: (i) the Dissolved Oxygen (DO), (ii) the Flow Rate, (iii) the Oxidation Reduction Potential (ORP), (iv) the Turbidity and (v) the Total Suspended Solids (TSS). The pH and the Temperature seemed not to be altered from dry to rainy weather. For the case of measurements undertaken by UV-VIS spectrometry, the absorbance values registered by the boundary wavelengths of the UV-VIS range (200 nm to 750 nm) seems to explain better the differences between variability of dry and wet weather days data, rather than for the wavelengths closer to the center of the UV-VIS range (for about 400 nm). Hence, considering the most explicative water quality and quantity parameters from PCA, the designed methodology was then applied to the time series registered during rainy days. A temporal delimitation of the rainfall events was obtained, which exposed an appropriate consistency. Regarding the identified rainfall events, association metrics (Pearson s Correlation Test, Average Mutual Information, Linear Models and Partial Least Squares Model) between different rainfall and water quality and quantity statistical characteristics per event (e.g. mean, standard deviation, entropy and duration) were undertaken, with the purpose of detecting recurrent relations between rainfall and water quality and quantity (for rainfall registered at different rain gauge stations). The results showed that: (i) Turbidity seems to be related with the duration of the rainfall pulses and with the mean rainfall height, (ii) DO seems to have an association with total volume of rainfall and with the rainfall pulse s entropy, (iii) flow rate was found to be related with mean rainfall height, standard deviation of rainfall heights and the mean rainfall intensity, (iv) TSS behavior was found to be linked with characteristics of rainfall such as the duration, the mean rainfall height, the standard deviation of the rainfall heights and the memory of the process (evaluated by the ACF of each specific rainfall pulse), (v) ORP seemed to be connected with the characteristics of rainfall events such as the duration, the Antecedent Dry Weather Period (ADWP), the total rainfall volume, the entropy and the standard deviation of the rainfall pulse(s). Rainfall registered at the Bosa rain gauge station seems to be more correlated with characteristics of the effluent in terms of quality and quantity, rather than Fontibon and Casablanca rain gauge stations. Preliminary insights showed that the principal sources of variability between the spatial influence of a given rain gauge station (in terms of the amount of recurrent) with different sub basins of the urban catchment are: (i) the distance to the rain gauge station which is mostly influencing a specific sub basin, (ii) the variability of the pipes slope at a given sub basin, (iii) the industrial land use regarding a sub basin, (iv) the mean pipes slope for a given sub basin and (v) the variability of pipes length at a sub basin.#-
El presente estudio se trazó como objetivo establecer la influencia de la lluvia sobre la calidad del agua en el efluente de una cuenca urbana mediante el uso de medición en alta resolución temporal. Los parámetros de calidad y cantidad de agua en el efluente de la cuenca urbana estudiada (Gibraltar: Bogotá, Colombia) se midieron mediante captores con tecnología uni-paramétrica, espectrometría UV-VIS (en cuanto a calidad) y medición ultrasónica (en cuanto a cantidad). Los registros de lluvia se efectuaron a través de tres estaciones de lluvia (Fontibon, Bosa y Casablanca) en proximidades de la cuenca urbana estudiada. Mediante el uso de técnicas de procesamiento de señales y análisis de series de tiempo (filtro de medianas, Step Detection y funciones de autocorrelación-ACF-), se propuso una metodología orientada a identificar aquellos periodos durante los cuales un parámetro dado de calidad o cantidad de agua se encuentra fluctuando por fuera de su comportamiento típico durante el tiempo seco. Mediante un Análisis de Componentes Principales (PCA) se estableció de manera preliminar qué parámetros de calidad y cantidad de agua explican en mayor medida las diferencias entre la variabilidad de tiempo seco y tiempo de lluvia. Los parámetros más explicativos medidos a través de captores con tecnología uni-paramétrica y ultrasónica fueron: (i) oxígeno disuelto (OD)...

Forecasting Local Climate for Policy Analysis : A Pilot Application for Ethiopia

Blankespoor, Brian; Pandey, Kiran Dev; Wheeler, David
Fonte: Banco Mundial Publicador: Banco Mundial
Português
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36.44%
This paper describes an approach to forecasting future climate at the local level using historical weather station and satellite data and future projections of climate data from global climate models (GCMs) that is easily understandable by policymakers and planners. It describes an approach to synthesize the myriad climate projections, often with conflicting messages, into an easily-interpreted set of graphical displays that summarizes the basic implications of the ensemble of available climate models. The method described in the paper can be applied to publicly-available data for any country and for any number of climate models. It does not depend on geographic scale and can be applied at the subnational, national, or regional level. The paper illustrates the results for future climate for Ethiopia using future climate scenarios projects by 8 global climate models. The graphical displays of nine possible future climate regimes (average temperature, precipitation and their seasonal distribution) for each grid-cell about 50km X 50 km). It also provides the probability associated with each of the nine-climate regimes.

Rainfall Variability, Occupational Choice, and Welfare in Rural Bangladesh

Bandyopadhyay, Sushenjit; Skoufias, Emmanuel
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Português
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46.33%
This study investigates the choice of occupational focus versus diversification between household members in rural Bangladesh as an autonomous and proactive adaptation strategy against ex ante local rainfall variability risks. The analysis combines nationally representative household level survey data with historical climate variability information at the Upazila level. The authors note that flood prone Upazilas may face reduced risks from local rainfall variability as compared with non-flood prone Upazilas. They find that two members of the same household are less likely to be self-employed in agriculture if they live in an area with high local rainfall variability. However, the occupational diversification strategy comes at a cost to households in terms of consumption welfare. The paper considers the effects of three policy actions, providing access to credit, safety net, and market. Access to market appears to be more effective in reducing the likelihood of costly within-household occupational diversification as an ex ante climate risk-reducing strategy as compared with access to credit and safety net.

Economics of Adaptation to Climate Change : Ethiopia

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Português
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36.39%
The report is part of a broader study, the Economics of Adaptation to Climate Change (EACC), which has two objectives: (a) to develop a global estimate of adaptation costs for informing international climate negotiations; and (b) to help decision makers in developing countries assess the risks posed by climate change and design national strategies for adapting to it. This paper is one of a series of country-level studies, where national data were disaggregated to more local and sector levels, helping to understand adaptation from a bottom-up perspective. Ethiopia is heavily dependent on rainfed agriculture. Its geographical location and topography in combination with low adaptive capacity entail a high vulnerability to the impacts of climate change. Historically the country has been prone to extreme weather variability. Rainfall is highly erratic, most rain falls with high intensity, and there is a high degree of variability in both time and space. Since the early 1980s, the country has suffered seven major droughts five of which have led to famines in addition to dozens of local droughts. Major floods also occurred in different parts of the country in 1988...

A point rainfall model for risk-based design

Heneker, T.; Lambert, M.; Kuczera, G.
Fonte: Elsevier Science BV Publicador: Elsevier Science BV
Tipo: Artigo de Revista Científica
Publicado em //2001 Português
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36.42%
The point rainfall model presented extends previous work on event-based rainfall models and overcomes some of their shortcomings. The model uses event-based data and can be calibrated using rainfall data substantially affected by missing or corrupted values. Particular attention was given to adequately simulating extreme storm rainfall events for use in hydrological risk assessment. The model is capable of simulating the inter-event time, storm duration, average event intensity and intra-event temporal characteristics. Conditioning of the average event rainfall intensity on rainfall duration and time of year is a feature of the model. Rainfall events are disaggregated using a conditional random walk on a dimensionless mass curve. Pluviograph data in 6 min increments from three Australian capital cities (Sydney, Brisbane and Melbourne) was used to calibrate the model parameters. It was found that the constrained random walk parameters were almost identical for the three cities. The model was tested using statistics not used in its calibration and the simulated intensity–frequency–duration extreme rainfall statistics compared very favorably with observed values. In addition, simulated aggregated statistics compared favorably with observed statistics from 30 min to monthly durations. The simulated annual rainfalls significantly underestimated the observed variability for Brisbane and Sydney...

Toward a reliable decomposition of predictive uncertainty in hydrological modeling: Characterizing rainfall errors using conditional simulation

Renard, B.; Kavetski, D.; Leblois, E.; Thyer, M.; Kuczera, G.; Franks, S.
Fonte: Amer Geophysical Union Publicador: Amer Geophysical Union
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
Relevância na Pesquisa
46.25%
This study explores the decomposition of predictive uncertainty in hydrological modeling into its contributing sources. This is pursued by developing data-based probability models describing uncertainties in rainfall and runoff data and incorporating them into the Bayesian total error analysis methodology (BATEA). A case study based on the Yzeron catchment (France) and the conceptual rainfall-runoff model GR4J is presented. It exploits a calibration period where dense rain gauge data are available to characterize the uncertainty in the catchment average rainfall using geostatistical conditional simulation. The inclusion of information about rainfall and runoff data uncertainties overcomes ill-posedness problems and enables simultaneous estimation of forcing and structural errors as part of the Bayesian inference. This yields more reliable predictions than approaches that ignore or lump different sources of uncertainty in a simplistic way (e.g., standard least squares). It is shown that independently derived data quality estimates are needed to decompose the total uncertainty in the runoff predictions into the individual contributions of rainfall, runoff, and structural errors. In this case study, the total predictive uncertainty appears dominated by structural errors. Although further research is needed to interpret and verify this decomposition...

Effect of winter rainfall on yield components and fruit green aromas of Vitis vinifera L. cv. Merlot in California

Mendez-Costabel, M.P.; Wilkinson, K.L.; Bastian, S.E.P.; Jordans, C.; McCarthy, M.; Ford, C.M.; Dokoozlian, N.
Fonte: Wiley Publicador: Wiley
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
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46.29%
impact of winter rainfall on the main compounds responsible for green aromas in grapes and wines, 3-isobutyl-2-methoxypyrazine (IBMP) and C6 compounds. These compounds are considered undesirable in grapes and wines above the threshold concentration. Methods and Results: One treatment subjected vines to average rainfall, while the other excluded winter rainfall by covering the ground with a plastic tarpaulin during the entire dormant season (November to mid-March). Irrigation for both treatments was maintained at a weekly rate of 70% of crop evapotranspiration until commercial harvest. Canopy growth, berry size and vine yield were significantly reduced by rainfall exclusion, and a significant increase in the fruit to pruning mass ratio was recorded from one season to another. Synthesis of IBMP was significantly greater in vines under normal rainfall, whereas C6 compounds were significantly different between treatments only at the end of the second season. Fruit and wine composition, mainly colour and mouthfeel compounds, were positively affected by the absence of rainfall in both years. Wine descriptive analysis showed that the lack of rainfall produced wines perceived as less green and of more intense fruit attributes in the first season. As a consequence of the reduction in vine growth...

Effects of time-series length and gauge network density on rainfall climatology estimates in Latin America

MAEDA EDUARDO EIJI; AREVALO TORRES JUAN; CARMONA MORENO Cesar
Fonte: Copernicus GmbH (Copernicus Publications) Publicador: Copernicus GmbH (Copernicus Publications)
Tipo: Articles in periodicals and books Formato: Online
Português
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36.38%
Despite recent advances in the development of satellite sensors for monitoring precipitation at high spatial and temporal resolutions, the assessment of rainfall climatology still relies strongly on ground-station measurements. The Global Historical Climatology Network (GHCN) is one of the most popular stations database available for the international community. Nevertheless, the spatial distribution of these stations is not always homogeneous and the record length largely varies for each station. This study aimed to evaluate how the number of years recorded in the GHCN stations and the density of the network affect the uncertainties of annual rainfall climatology estimates in Latin America. The method applied was divided in two phases. In the first phase, Monte Carlo simulations were performed to evaluate how the number of samples and the characteristics of rainfall regime affect estimates of annual average rainfall. The simulations were performed using gamma distributions with pre-defined parameters, which generated synthetic annual precipitation records. The average and dispersion of the synthetic records were then estimated through the L-moments approach and compared with the original probability distribution that was used to produce the samples. The number of records (n) used in the simulation varied from 10 to 150...

Climate Resilient Ningbo Project : Local Resilience Action Plan, Volume 1. Final Report

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Country Environmental Analysis (CEA); Economic & Sector Work
Português
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36.4%
Ningbo serves as the Chinese pilot city for the World Bank Climate Resilient Cities (CRC) Program. The CRC program aims to, prepare local governments in the East Asia region to better understand the concepts and consequences of climate change; how climate change consequences contribute to urban vulnerabilities; and what is being done by city governments in East Asia and around the world to actively engage in learning capacity building, and capital investment programs for building sustainable, resilient communities. This local resilience action plan (LRAP) had four parts. Part one investigated natural hazards weather observations and climate models. Seven key climatic parameters were selected: temperature, rainfall, drought, heat wave, flood, tropical cyclone, and sea level rise. Part two examined how the city functions, and pursues socio-economic development through a city vulnerability assessment. The qualitative, city vulnerability assessment was based on five sectors- people, infrastructure, environment...

Developing Rainfall-Based Index Insurance in Morocco

Skees, Jerry; Gober, Stephanie; Varangis, Panos; Lester, Rodney; Kalavakonda, Vijay
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
Português
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36.39%
Cereal production accounts for about seventy percent of all agricultural land in Morocco. Cereal producer prices, influenced by the government, are higher than world prices. Production is divided into six broad agro-climatic zones. About half of cereal production is concentrated in the favorable, and intermediate zones; the rest occurs mostly in less favorable (arid and semi-arid) zones, with average annual rainfall below 450 millimeters. The authors assess the feasibility of rainfall-based index insurance, to provide effective, low-cost drought insurance for Moroccan farmers, and rural dwellers. Their analysis focuses on Morocco's three main cereal crops - hard wheat, soft wheat, and barley - using data on annual production, and planting from 1978-99. Maize is included in some of the analysis. The benefits of this program over the traditional insurance scheme are that it minimizes the risk of moral hazard, and adverse selection, and promotes a streamlined pay-out-process. These features make the program more attractive to international re-insurers...

Análise da variabilidade da precipitação pluvial na bacia do rio Paranapanema, em diferentes escalas; Analysis of rainfall variability in the Paranapanema river basin using different scales

Maria Alice Borges Batista
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/08/2015 Português
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36.53%
Este trabalho foi desenvolvido com o objetivo de avaliar a dinâmica pluvial dentro dos limites da bacia do rio Paranapanema, através da variabilidade das chuvas. Foram usadas séries de precipitação pluviométricas retiradas do site Hidroweb, da Agencia Nacional de Águas (ANA), com as quais foram trabalhados os dados diários, médias mensais, desvio padrão, coeficiente de variação, máximo, mínimo, amplitude, anomalias, Índice de Anomalia de Chuva (IAC) e fator R da Equação Universal de Perda de Solo para dois recortes temporais 1976 a 2010 (34 anos) e de 1950 a 2010 (60 anos). Também foram analisados alguns anos de El Niño (1982, 1983, 1992, 1997, 2002 e 2006) e La Niña (1976, 1984, 1985, 1988, 1996 e 2008). Foram calculados Índices de Concentrações (IC ou CI da sigla em Inglês Concentration Index), para os dados diários, com intervalo de 1 mm. Também se analisou a distribuição espacial e temporal das séries de dados de chuva para a avaliação da variabilidade pluviométrica da área de estudo. Alguns resultados obtidos mostram que ao sul e sudeste da bacia, onde estão às altitudes mais elevadas, as precipitações pluviométricas foram maiores e mais regulares para os recortes temporais estudados. Os cálculos do desvio padrão mostram que houve uma variabilidade significativa...

Rainfall interception by olive trees in relation to leaf area

Gómez Calero, José Alfonso; Giráldez, Juan Vicente; Fereres Castiel, Elías
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 132442 bytes; application/pdf
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Interception of rainfall may be an important component of the water balance of rainfed olive orchards. To quantify the magnitude of interception by olive trees we conducted measurements during 1996 and 1997 in two orchards at Cordoba, Spain, on trees which differed in leaf areas. Interception amounted to about 8% of gross rainfall in an orchard that had an average leaf area index (LAI) of 1.1. The measurements were then used to calibrate and validate a model of interception which was subsequently used to compute average annual interception for a 7-year-period (1982–1989) at Cordoba. Three hypothetical orchards were assumed, ranging in LAI values from 0.3 to 4.8; such extreme values represent traditional rainfed plantings and intensive irrigated orchards, respectively. Relative interception varied from 7% at 0.3 LAI to 25% at 4.8 LAI of the average annual rainfall at Cordoba (606 mm). Interception represents a significant component of the seasonal water balance of olive orchards, particularly in the case of intensive plantings where the calculation of net irrigation requirements should include an estimate of interception loss.; Peer reviewed

Heavy daily-rainfall characteristics over the Gauteng Province

Dyson,Liesl L
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2009 Português
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Daily rainfall over the Gauteng Province, South Africa, was analysed for the summer months of October to March using 32-yr (1977 to 2009) daily rainfall data from about 70 South African Weather Service stations. The monthly and seasonal variation of heavy rainfall occurrences was also analysed. Three 24-h heavy rainfall classes are defined considering the area-average rainfall. A significant rainfall event is defined when the average rainfall exceeds 10 mm, a heavy rainfall event when the average rainfall exceeds 15 mm and a very heavy rainfall event when the average rainfall exceeds 25 mm. January months have the highest monthly average rainfall as well as the highest number of heavy and very heavy rainfall days. The month with the second-highest number of heavy and very heavy rainfall days is February followed by March and October. December has the second-highest monthly average rainfall and the most days with rain. However, it is also the month with the lowest number of heavy and very heavy rainfall days. The highest 24-h rainfall recorded at a single station during the 32-yr period was 300 mm in December 2006. However, rainfall exceeding 115 mm at a single rainfall station in the Gauteng Province is very rare and does not occur every year. January months receive these events more than any other month but this only transpires in approximately a third of years. The central and north-western parts of the Province experience the most events where the rainfall at a single station surpasses 75 and 115 mm. With regard to seasonal rainfall...