scholarly journals Identificação de Ilhas de Calor na Cidade de Campina Grande-PB Utilizando Sensoriamento Remoto (Identification of Heat Islands in Campina Grande City-PB Using Remote Sensing)

2016 ◽  
Vol 9 (2) ◽  
pp. 614 ◽  
Author(s):  
Elânia Daniele Silva Araújo

A intensa urbanização causa diversos problemas de natureza ambiental, climática e social. O crescimento não planejado da população urbana e a remoção da vegetação são fatores que intensificam estes problemas. As temperaturas na cidade são significativamente mais quentes do que as suas zonas rurais circundantes devido às atividades humanas. As intensas mudanças espaciais em áreas urbanas, promovem significativo aumento na temperatura, causando o chamado efeito de Ilha de Calor Urbano (ICU). Campina Grande é uma cidade de tamanho médio que experimentou um crescimento desordenado, desde o tempo do comércio de algodão e, como qualquer cidade de grande ou médio porte, sofre alterações em seu espaço. Dessa forma, este estudo teve por objetivo analisar a variabilidade espaço-temporal da temperatura da superfície (Ts) e detectar ICU, através de técnicas de sensoriamento remoto. Para o efeito, foram utilizadas imagens dos satélites Landsat 5 e 8, dos anos de 1995, 2007 e 2014. Aumentos da Ts foram bem evidentes e foram detectadas duas ICU. Campina Grande mostra um padrão de tendência: o crescimento urbano não planejado é responsável por mudanças no ambiente físico e na forma e estrutura espacial da cidade, o que se reflete sobre o microclima e, em última análise, na qualidade de vida das pessoas.   ABSTRACT The intense urbanization causes several problems of environmental, climate and social nature. The unplanned growth of urban population and the vegetation removal are factors that deepen these problems. Temperatures in the city are significantly warmer than its surrounding rural areas due to human activities. Large spatial changes in urban areas promote significant increase in temperature, causing the so-called Urban Heat Island effect (UHI). Campina Grande is a medium-sized town that experienced an uncontrolled growth since the time of the cotton trade and like any large or medium-sized city, undergoes changes in its space. Therefore, this study aimed to analyze surface temperature spatial and temporal variability and to detect potential UHI, through remote sensing techniques. Spectral images from Landsat 5 and 8 satellites were used. Using images from years 1995, 2007 and 2014, considerable increases in temperature were identified and two UHI were recognize. Campina Grande shows a trend pattern: the urban unplanned growth is responsible for changes in the physical environment and in the form and spatial structure of the city, reflecting on people quality of life. Keywords: change detection, surface temperature, heat islands, urbanization.   

2019 ◽  
Vol 12 (6) ◽  
pp. 2041
Author(s):  
Gislene Figueiredo Ortiz Porangaba ◽  
Margarete Cristiane de Costa Trindade Amorim

A qualidade dos ambientes urbanos tem se mostrado de maneira inadequada para parcela significativa da população, devido ao fato de não se considerar, no seu processo de expansão territorial, as características físicas desses ambientes. No intuito de amenizar os problemas relacionados à qualidade desses ambientes, particularmente no que se refere às características da temperatura e à geração de ilhas de calor de superfície, a comunidade científica vem desenvolvendo formas de análise para auxiliar no planejamento ambiental das cidades tendo o sensoriamento remoto como grande aliado. Nas análises acerca das ilhas de calor de superfície, o sensoriamento remoto auxilia na representação da temperatura dos alvos urbanos em relação ao entorno próximo e na avaliação da cobertura vegetal, que é um importante elemento para amenizar as ilhas de calor superficiais. Nesse sentido, no presente artigo tem-se por objetivo analisar a cobertura vegetal por meio do Índice de Vegetação por Diferença Normalizada (NDVI) e sua interferência na temperatura da superfície nas cidades de Assis, Cândido Mota, Maracaí e Tarumã (São Paulo/Brasil). Para isso foram utilizadas imagens do satélite Landsat 8, banda 10, para o cálculo da temperatura dos alvos e as bandas 4 e 5 para o cálculo do NDVI.  Pode-se concluir por meio da análise do NDVI que a vegetação exuberante e/ou ativa (alto NDVI) tem papel fundamental na amenização das temperaturas dos alvos. Por outro lado, NDVI baixo, devido à alta densidade construtiva nas áreas urbanas ou em período de estiagem, particularmente nas áreas rurais próximas, favorece o aquecimento superficial. Heat Islands in Cities in the Interior of the State of São Paulo, Brazil A B S T R A C TThe quality of urban environments has proven inappropriate for a significant portion of the population due to a failure to consider, in their territorial expansion process, the physical characteristics of these environments. In order to mitigate issues related to the quality of these environments, particularly regarding characteristics of temperature and generation of surface heat islands, the scientific community has developed analysis methods to assist in the environmental planning of cities, using remote sensing as a key ally. In the analysis of surface heat islands, remote sensing assists in the representation of the temperature of urban targets in relation to the near surroundings and the assessment of the vegetation, which is a key element to mitigate surface heat islands. In this sense, this paper aims to analyze the vegetation cover using the Normalized Difference Vegetation Index (NDVI) and its interference on surface temperature in the cities of Assis, Cândido Mota, Maracaí and Tarumã (São Paulo, Brazil). To do that, we used images from the Landsat 8 satellite, band 10, to calculate the temperature of the targets, and bands 4 and 5, to calculate the NDVI. It can be concluded through the NDVI analysis that the exuberant and/or active vegetation (high NDVI) plays a key role in reducing temperatures in the targets. On the other hand, a low NDVI, due to the high building density in urban areas or the dry season, particularly in nearby rural areas, favors surface heating.Keywords: Remote sensing, NDVI, Surface temperature, Urban climate.


2021 ◽  
pp. 2110-2121
Author(s):  
Ahmed F. Hassoon ◽  
Abdulrahman B. Ali

Heat island is known as the increases in air temperature through large and industrial cities compared to surrounding rural areas. In this study, remote sensing technology is used to monitor and track thermal variations within the city center of Baghdad through Landsat satellite images and for the period from 2000 to 2015. Several processors and treatments were applied on these images using GIS 10.6 and ERDAS 2014, such as image correction and extraction, supervised classification, and selection of training samples. Urban areas detection was resulted from the supervised classification linked to the temperature readings of the surface taken from the thermal bands of satellite images. The results showed that the surface temperature of the city of Baghdad increased by 8 degrees Celsius in 15 years. This is due to the increase in the expansion of the urban areas type of land use, where the human activity, especially after 2003, caused increased buildup area to about 198.41 km2. All these changes occurred at the expense of many green regions which were reduced, with the transformation of open and agricultural areas to residential, commercial, and industrial uses. Increases in surface temperature resulted increases in air temperature, where the minimum temperature showed larger increases relative to maximum temperature (about 1.44 and 0.76 ºC, respectively).


HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 509A-509
Author(s):  
Derald A. Harp ◽  
Edward L. McWilliams

Urban areas have average annual temperatures 2–3°C warmer than surrounding rural areas, with daily differences of 5–6°C common. A suggested reason for this temperature difference is the extensive use of concrete, asphalt, and other building materials in the urban environment. Vegetation can moderate these temperatures by intercepting incoming radiation. The influence of vegetation patterns on the magnitude of urban and micro-urban “heat islands” (UHI and MUHI, respectively) is compared for several cities including Houston, Austin, College Station, and Ft. Worth, Texas; Huntsville, Ala.; and Gainesville, Fla. Temperatures for all cities studied were greatest in the built-up areas and dropped off in suburban areas and adjacent rural areas. In Houston, surrounding rice fields were 3–5°C cooler than urban areas. Heavily built-up areas of Austin were 2–4°C warmer than parks and fields outside of the city. In all of the cities, large parks were typically 2–3°C cooler than adjacent built-up areas. Large shopping malls varied in nocturnal winter and summer temperature, with winter temperatures near door openings 2–3°C warmer, and summer daytime temperatures as much as 17°C cooler beneath trees. This effect seemed to persist at the microclimatic scale. Areas beneath evergreen trees and shrubs were warmer in the winter than surrounding grass covered areas. Video thermography indicated that the lower surfaces of limbs in deciduous trees were warmer than the upper surfaces. Overall, vegetation played a significant role, both at the local and microscale, in temperature moderation.


2020 ◽  
Author(s):  
Sarah Safieddine ◽  
Maya George ◽  
Cathy Clerbaux ◽  
Ana Paracho ◽  
Anne Boynard ◽  
...  

<p>IASI is a versatile mission, allowing the measurement of both meteorological parameters such as temperature and atmospheric composition for infrared absorbing species. With its long observation record and frequent overpasses, IASI is able to follow changes at different spatial scales. We studied IASI’s capability to track the anthropogenic signature associated with large cities, both in terms of temperature fingerprint (urban heat islands) and carbon monoxide (CO) content, a good tracer of human activity (transport, heating, and industrial activities). For this study we averaged the IASI data available since the launch of the first IASI, in order to increase the signal to noise, and allow discriminating the city from its surroundings. For skin temperatures we show that some cities experience much warmer temperatures than nearby rural areas, with day and night differences, whereas other urban areas appear as cold urban islands when surrounded by deserts Examples will be shown and compare with MODIS observations. For CO emitted by human activities, we identified some cities that stand out from their background, and were able to compare their CO associated signatures with measurements provided by other available spaceborne instruments such as Mopitt and TROPOMI.</p>


2018 ◽  
Vol 7 (7) ◽  
pp. 408
Author(s):  
Rafaela Lisboa Costa

The objective of this study was to identify heat islands and to evaluate the degree of thermal comfort / discomfort in selected urban areas. Landsat 5 and 8 satellite images were use in the thermal bands and, as a complement, observed data from meteorological stations present in the chosen cities. In order to evaluate heat islands and the degree of thermal comfort / discomfort, the surface temperature was obtain and the Kawamura Discomfort Index (IDK) was use. By means of surface temperature images, it was possible to identify the heat islands in these areas. For IDK, in spite of this index, in general, to present the situation of comfort, for some areas were observe situations of discomfort and heat stress due to the heat, mainly in the year of 2016, considered one of the hottest of this century. The use of observed data was necessary in order to corroborate with the information of the satellites.


2021 ◽  
Vol 12 (3) ◽  
pp. 113-129
Author(s):  
Albert Berila ◽  
◽  
Florim Isufi ◽  

Urban areas, compared to peripheral and rural areas, have higher temperatures which are caused by a series of unplanned activities that are undertaken by humans. Such a thing leads to the emergence of the Surface Urban Heat Island (SUHI) phenomenon. In this paper, summer SUHI is determined through the calculation of LST for the Municipality of Prishtina using GIS and Remote Sensing techniques. To make this calculation, the Landsat 8 satellite image with 0% cloud cover was used. From the calculations made it turns out that the pixels with the highest value of LST are found in those parts where the urban area appears, where there are numerous constructions with impermeable materials, as well as in those areas where there are bare surfaces. Whereas, the pixels with lower values of LST appear in those parts where there are vegetation and water bodies, making these areas fresher. The SUHI phenomenon makes the lives of citizens difficult, therefore, such information is very important for the leaders and urban planners of the city of Prishtina, so that they take a series of steps towards minimizing such an effect in order to the life of the citizens to be as healthy as possible.


2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Małgorzata Lesińska-Sawicka

Abstract Introduction Cervical cancer and its etiopathogenesis, the age of women in whom it is diagnosed, average life expectancy, and prognosis are information widely covered in scientific reports. However, there is no coherent information regarding which regions—urban or rural—it may occur more often. This is important because the literature on the subject reports that people living in rural areas have a worse prognosis when it comes to detection, treatment, and life expectancy than city dwellers. Material and methods The subjects of the study were women and their knowledge about cervical cancer. The research was carried out using a survey directly distributed among respondents and via the Internet, portals, and discussion groups for women from Poland. Three hundred twenty-nine women took part in the study, including 164 from rural and 165 from urban areas. The collected data enabled the following: (1) an analysis of the studied groups, (2) assessment of the respondents’ knowledge about cervical cancer, and (3) comparison of women’s knowledge depending on where they live. Results The average assessment of all respondents’ knowledge was 3.59, with women living in rural areas scoring 3.18 and respondents from the city—4.01. Statistical significance (p < 0.001) between the level of knowledge and place of residence was determined. The results indicate that an increase in the level of education in the subjects significantly increases the chance of getting the correct answer. In the case of age analysis, the coefficients indicate a decrease in the chance of obtaining the correct answer in older subjects despite the fact that a statistically significant level was reached in individual questions. Conclusions Women living in rural areas have less knowledge of cervical cancer than female respondents from the city. There is a need for more awareness campaigns to provide comprehensive information about cervical cancer to women in rural areas. A holistic approach to the presented issue can solve existing difficulties and barriers to maintaining health regardless of the place of life and residence. Implication for cancer survivors They need intensive care for women’s groups most burdened with risk factors.


10.29007/hbs2 ◽  
2019 ◽  
Author(s):  
Juan Carlos Valdiviezo-Navarro ◽  
Adan Salazar-Garibay ◽  
Karla Juliana Rodríguez-Robayo ◽  
Lilián Juárez ◽  
María Elena Méndez-López ◽  
...  

Maya milpa is one of the most important agrifood systems in Mesoamerica, not only because its ancient origin but also due to lead an increase in landscape diversity and to be a relevant source of families food security and food sovereignty. Nowadays, satellite remote sensing data, as the multispectral images of Sentinel-2 platforms, permit us the monitor- ing of different kinds of structures such as water bodies, urban areas, and particularly agricultural fields. Through its multispectral signatures, mono-crop fields or homogeneous vegetation zones like corn fields, barley fields, or other ones, have been successfully detected by using classification techniques with multispectral images. However, Maya milpa is a complex field which is conformed by different kinds of vegetables species and fragments of natural vegetation that in conjunction cannot be considered as a mono-crop field. In this work, we show some preliminary studies on the availability of monitoring this complex system in a region of interest in Yucatan, through a support vector machine (SVM) approach.


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