970 resultados para temperatura mínima do ar


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Baseado no conjunto de dados diários de precipitação e temperatura do ar de oito estações meteorológicas sobre o Pará, pertencentes ao INMET, disponíveis no período 1961-2007, foram calculados índices de extremos climáticos através da metodologia estatística do software RClimdex. Utilizando-se ainda um conjunto de dados mensais de precipitação de 134 estações pluviométricas da Amazônia oriental, provenientes da ANA e INMET, foram analisadas as tendências anual e sazonal num período de 25 a 37 anos (1970-2009), através da aplicação da estatística não-paramétrica (teste de Mann-Kendall e método de Sen). E por fim, utilizaram-se dados de desmatamento do PRODES/INPE no período 2000-2007, para analisar a possível influência do desmatamento nas tendências de precipitação anual e sazonal do Pará. Considerando os índices de extremos climáticos referentes aos dados diários de precipitação, constatou-se que a variabilidade interanual dos índices possui relações com os episódios ENOS e as fases do Dipolo do Atlântico. Para os extremos climáticos de temperatura evidenciaram-se reduções sistemáticas dos dias frios (TX10p) e aumentos sistemáticos da mínima da máxima temperatura (TXN), da percentagem de noites quentes (TX90p) e da temperatura máxima da máxima (TXX). Os resultados das tendências da precipitação anual usando os testes não-paramétricos evidenciaram que do total de 134 estações, em torno de 51% apresentam tendências positivas e 41% tendências negativas sobre a Amazônia oriental. Contudo, essas tendências anuais “mascararam” de certa forma as tendências sazonais, cujos resultados mostraram-se mais diversificados, explicando melhor os aspectos da variabilidade climática regional. Para o trimestre MAM, observaram-se 99 estações (74%) com tendências positivas, indicando que a quantidade de precipitação durante o período chuvoso principal vem aumentando sistematicamente durante a última década. Em DJF, notaram-se 45 estações (34%) com tendências positivas e 78 estações (58%) com tendências negativas. Por outro lado, nos trimestres que englobam o período seco ou menos chuvoso verificaram-se tendências sazonais predominantemente negativas, com 84 estações (62%) em JJA e 89 estações (66%) em SON. Portanto, a evidência observacional de que a precipitação do período seco encontra-se em diminuição gradativa nas últimas décadas corrobora com a hipótese de que o desmatamento associa-se com a redução da precipitação em escala regional, porém sugere-se que isso ocorra em escala de tempo sazonal.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Pós-graduação em Engenharia Mecânica - FEG

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

It is known that the urban environment modifies the energy balance between the surface and the atmosphere, causing changes in temperature, relative humidity, among other things, opening the way for studies aimed at urban climatology. Based on the theme of urban climate, this research focuses on the city of Assis, located west of São Paulo. The generation of urban climate is a result of various factors, among which stand out: the use and different land use, the thermodynamic properties of buildings, number of buildings in the urban, socioeconomic activities, etc.. In general, this increases the temperature and reducing relative humidity, providing thermal discomfort. The rural environment is used for comparison studies to this theme by presenting different characteristics in relation to the structure, morphology and urban functionality. The main objective of this study is to determine the characteristics of temperature and humidity environments with the habits and occupations of the different soils in winter, at night, one inserted into the urban fabric of Assis and the other in the rural environment, to verify for evidence of changes in climatic elements because of urbanization. To collect the data will be used mini automatic weather stations that record data on temperature and humidity. For analysis of the results will be made between the data obtained in the city and the countryside, developing graphics application using Excel to tabulate the data. It was found that there were differences in the thermo-hygrometric data collection points, showing a specific urban climate in the city of Assis

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This work deals with the thermal load study of a fictitious aircraft as well as scaling, in terms of the airflow and temperature of the air conditioning system, for heating and cooling of the its internal environment, aiming the thermal comfort of occupants. The first part is presented the techniques and methods utilized for modeling different heat exchanges that occur in the aircraft and then allowed to calculate the total heat load and the airflow and temperature necessary to comply with the requirements of the thermal comfort. Techniques to determine the basic parameters, as convection coefficient and global coefficient of heat exchange, are also presented. The work aims to develop a program, using a computational tool, to automate the calculations so that facilitate this study. It also allows to be used for other airplanes just changing parameters and the control variables related to the specific project. Finally the program performs calculations for a fictitious airplane, to analyze its functionality and the influence of parameters involved in the temperature controls. The program allowed analyzing the sensitivity of portions of the thermal load and the corresponding parameters of influence, as well as the scaling of the air conditioning in terms of airflow and temperature. It was considered, despite the simplifications, a good approximation to the actual values and then can be used in development of the other airplanes

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The study and selection of an equipment of air conditioner for any type of environment, should be made without overestimate or undersizing the project. The undersizing does not provide an adequate comfort temperature if the environment is too hot because the air conditioner does not remove all the heat necessary in the environment. But if the project is oversized, energy consumption is higher and there is an unnecessary cost. To prevent these failures is necessary to make a calculation of the thermal load on the environment and choose the equipment that has a higher cooling capacity than the calculated heat load and closer to the calculated heat load. In this graduate work will be chosen an air-conditioned equipment for bus, showing the calculations made for the thermal load for various types of heat gain in this type of vehicle. The thermal load on vehicles is more complicated to calculate than in areas because there are several factors that vary with the movement of the vehicle. It will also explain the compression refrigeration cycle, which is the cooling system used in vehicles because it is weightless, compact and lower cost. From the calculated heat load, it will be chosen an air conditioner that best suits the project and, finally, a brief presentation of the selected equipment will be made

Relevância:

30.00% 30.00%

Publicador:

Resumo:

This work is about a development of a vacuum solar water heater. To accomplish this, some measurements were made, such as flow, water temperature and room temperature, relative humidity, solar power density and wind speed. It first presents a brief explanation about the global situation in relation to the accelerated use of exhaustible energy sources which can result in a breakdown of these for future generations. From this, is proposed to analyze this solar water heater with vacuum tubes during the winter season in Brazil southeastern region, under different environmental conditions. From such ideas became possible to prove through the experimental part, calculations and graphical results that technology and the performance of this device are technical and economically viable, according to the life cycle of this. It was also found that the average monthly production in a maximum heat stroke situation was 193,33kWh and minimum isolation was 57,76kWh. This reveals that this instrument should start to be examined more closely by all, as a way to reduce the use of electricity, which will protect the environment without reducing the comfort of people