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What is urban heat island?

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An urban heat island refers to the phenomenon where urban areas experience significantly higher temperatures than their rural surroundings due to human activities like buildings, roads, and industrial processes that absorb and retain heat. This effect is influenced by factors like reduced vegetation, increased concrete surfaces, and waste heat generation, leading to elevated temperatures in cities compared to rural areas. Studies have shown that urban heat islands can impact energy consumption, air quality, and public health. Additionally, research has highlighted the importance of understanding heat conduction in urban environments, especially in relation to cooling systems and thermal protection. Furthermore, investigations into specific heat behaviors of gases near critical densities have provided insights into how heat is managed and distributed in different environments.

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Open access•Journal Article•DOI Heat of Immersion of Some Powders in Surfactant Solutions Kenjiro Meguro, Masumi Koishi, Nobuo Okabe - Show less +2 more 01 Jan 1965-The Journal of the Society of Chemical Industry, Japan 2 Citations	Not addressed in the paper.
Open access•Journal Article Study of operational characteristics of left-hand entrance and exit ramps on urban freeways R D Worral, J S Drake, J H Buhr, T J Soltman - Show less +3 more 01 Jan 1965-Highway Research Record 2 Citations	Not addressed in the paper.
Journal Article•DOI A simple numerical solution for heat conduction in a solid with a receding surface J. J. Brogan 01 Jan 1965-Journal of Spacecraft and Rockets 1 Citations	Not addressed in the paper.
Book Chapter•DOI AN INVESTIGATION OF THE NATURE OF THE SPECIFIC HEAT IN THE NEIGHBORHOOD OF THE CRITICAL POINT OF 4He M. R. Moldover, W. A. Little - Show less +1 more 01 Jan 1965	Not addressed in the paper.
Book Chapter•DOI The Performance of Air and Ground Source Heat Pumps in a Northern Climate: Fonctionnement des pumpes à chaleur avec l'air ou le sol comme sources de chaleur, dans un climat nordique Torstein Nygård 01 Jan 1965 2 Citations	Not addressed in the paper.

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Related Questions

How does global warming effect urban heat islands?5 answersGlobal warming intensifies urban heat islands (UHIs) by exacerbating heatwaves and increasing temperatures in urban areas. As temperatures rise globally, UHIs experience more intense and prolonged heatwaves, deepening the turbulent boundary layer height and modifying urban energy balances. Additionally, urbanization and global warming contribute to changes in precipitation patterns, with UHIs causing a decrease in urban-induced precipitation in warmer climates. The rise in long-term surface temperatures due to global warming makes urban areas more susceptible to UHIs, which are driven by factors like changes in land surfaces and anthropogenic heat. Urbanization intensifies local and regional land surface warming, with a global mean intensity of 1.1°C in urban areas, and this effect is expected to increase significantly by the end of the century. Overall, global warming exacerbates UHIs by increasing temperatures and intensifying heatwaves in urban areas.

What is the parameters of urban heat island effect?5 answersThe parameters of the urban heat island (UHI) effect include air temperature, low cloudiness, wind speed, total cloudiness, relative humidity, surface temperature, and cloud cover. These parameters have been studied in various locations such as Moscow, Hong Kongand Ibadan. The UHI intensity is influenced by these parameters, with some parameters showing a stronger relationship than others. For example, low cloudiness and amplitudes of diurnal air temperature have a close relationship with UHI intensity, while wind speed, total cloudiness, and relative humidity have a slightly weaker but still significant relationship. Wind speed is found to be a significant predictor of UHI intensity, with UHI weakening with increasing wind speed. The relationship between UHI intensity and cloud cover and relative humidity is negative and weak. Overall, these parameters play a crucial role in understanding and mitigating the effects of the urban heat island phenomenon.

What are the primary natural factors that contribute to Urban Heat Island (UHI)??5 answersThe primary natural factors that contribute to Urban Heat Island (UHI) are climatic elements and city-building factors. Climatic elements include sunlight, wind speed and direction, cloud cover, soil and air humidity, precipitation, latitude, seasonal change, topography, and proximity to rivers and the sea. City-building factors, on the other hand, are controllable and primarily connected to city planning and building. These factors include low albedo materials, urban geometry, high density, and anthropogenic heat. The bio-geophysical effects of land cover classes also play a role in UHI, with major cities being significantly warmer than surrounding suburban or rural areas. Additionally, the anthropic alteration of the natural environment by urban expansion, impermeable surfaces, and anthropic activities contributes to the UHI effect. Overall, both natural climatic elements and human-induced city-building factors contribute to the formation and intensity of UHI.

What are the causes of Urban heat island?5 answersThe causes of Urban Heat Island (UHI) include the destruction of trees, low albedo materials, urban canopy, and human gathering. Other factors contributing to UHI are the vast amounts of heat generated by urban structures as they consume and re-radiate solar energy and anthropogenic heat sources. Land surface temperature (LST) can be reduced by replacing asphalt pavements with concrete pavements, leading to a decrease in the global LST of the studied areas. The increase in temperature in cities is also influenced by urban morphology, such as densely built-up areas, which contribute to the UHI effect. Additionally, decreased plant cover and land-use changes have been linked to the rising trend in UHI. These factors alter the urban ecological balance, atmospheric environment, and public health, making it crucial to address UHI urgently.

What is urban heat island?5 answersThe urban heat island (UHI) is a localized climatic phenomenon where temperatures in cities gradually rise compared to their rural surroundings. It is caused by the introduction of artificial surfaces in urban areas, which alter the aerodynamic, radiative, thermal, and moisture properties of the region. The UHI effect can be observed during both day and night, with the urban area experiencing higher temperatures than the surrounding rural areas. The intensity of the UHI varies across cities and is influenced by factors such as city size, physical characteristics, and dynamic weather conditions. Contrary to previous beliefs, recent studies have shown that the intensity of the UHI tends to decrease with increasing temperature in most cities, primarily driven by changes in rural areas. Urban green infrastructure, including trees and forests, has the potential to mitigate the UHI effect and enhance the thermal comfort of urban populations.

What are the reasosn behaind the urban heat iland phenomena?2 answersThe urban heat island phenomenon is influenced by various factors. Climatic elements such as sunlight, wind speed and direction, cloud cover, humidity, precipitation, latitude, seasonal change, topography, and proximity to rivers and the sea play a role in the formation and growth of urban heat islands. Additionally, city-building factors, including urban planning and design, also contribute to the development of urban heat islands. The increase in urbanization and the expansion of developed areas lead to higher baseflow stream temperatures and temperature surges in urban streams, creating a hydrological urban heat island. The rapid development and population growth in cities like Jakarta have intensified the urban heat island effect, resulting in higher temperatures and climate change challenges. It is important to note that the traditional urban-rural dichotomy used to define urban heat islands may not adequately address the complexities of the phenomenon, and a more holistic approach is needed.

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