Search results for "Urban heat Island"
showing 10 items of 47 documents
Heart healthy cities : Genetics loads the gun but the environment pulls the trigger
2021
Abstract The world’s population is estimated to reach 10 billion by 2050 and 75% of this population will live in cities. Two-third of the European population already live in urban areas and this proportion continues to grow. Between 60% and 80% of the global energy use is consumed by urban areas, with 70% of the greenhouse gas emissions produced within urban areas. The World Health Organization states that city planning is now recognized as a critical part of a comprehensive solution to tackle adverse health outcomes. In the present review, we address non-communicable diseases with a focus on cardiovascular disease and the urbanization process in relation to environmental risk exposures inc…
Emissivity mapping over urban areas using a classification-based approach: Application to the Dual-use European Security IR Experiment (DESIREX)
2012
Abstract In this work a methodology to provide an emissivity map of an urban area is presented. The methodology is applied to the city of Madrid (Spain) using data provided by the Airborne Hyperspectral Scanner (AHS) in 2008. From the data a classification map with twelve different urban materials was created. Each material was then characterized by a different emissivity, whose values were obtained from the application of the TES algorithm to in situ measurements and values extracted from the ASTER spectral library. This new emissivity map could be used as a basis for determining the temperature of the city and to understand the urban heat island effect in terms of spatial distribution and…
Forecasting green roofs’ potential in improving building thermal performance and mitigating urban heat island in the Mediterranean area: An artificia…
2023
Green roofs are widely used in hot or cold climates mainly because they are capable to improve the energy efficiency of buildings and, when implemented at a large scale, reducing air pollution and the urban heat island effect (UHI) in urban contexts. Artificial Neural Network (ANN) black-box algorithms are a valid alternative to studying complex systems. However, the literature highlights - quite surprisingly – none of the available research refers to coupling ANNs and green roofs in the Mediterranean area, where green roofs are instead considered one of the most suitable technologies to reduce the high cooling demand. Therefore, the objective of this research work is to create and validate…
Impact of spatial resolution and satellite overpass time on evaluation of the surface urban heat island effects
2012
Abstract Surface Urban Heat Island (SUHI) effect is defined as the increased surface temperature in urban areas in contrast to surrounding cooler temperatures in rural areas. In this paper, we study the characteristics that a spaceborne sensor must satisfy in terms of spatial resolution and overpass time to properly monitor the SUHI effect. For this, Land Surface Temperature (LST) maps, generated at different spatial resolution using the Airborne Hyperspectral Scanner (AHS) imagery, and in situ data of air temperature and LST obtained from the framework of the Dual-use European Security IR Experiment 2008 have been considered for the city of Madrid (Spain). The results showed that (1) spati…
Temperature Inversion Breakup with Impacts on Air Quality in Urban Valleys Influenced by Topographic Shading
2015
AbstractUrban valleys can experience serious air pollution problems as a combined result of their limited ventilation and the high emission of pollutants from the urban areas. Idealized simulations were analyzed to elucidate the breakup of an inversion layer in urban valleys subject to a strong low-level temperature inversion and topographic effects on surface heating such as topographic shading, as well as the associated air pollution transport mechanisms. The results indicate that the presence and evolution in time of the inversion layer and its interplay with an urban heat island within the valley strongly influence the venting of pollutants out of urban valleys. Three mechanisms of air …
Night Thermal Unmixing for the Study of Microscale Surface Urban Heat Islands with TRISHNA-Like Data
2019
International audience; Urban Heat Islands (UHIs) at the surface and canopy levels are major issues in urban planification and development. For this reason, the comprehension and quantification of the influence that the different land-uses/land-covers have on UHIs is of particular importance. In order to perform a detailed thermal characterisation of the city, measures covering the whole scenario (city and surroundings) and with a recurrent revisit are needed. In addition, a resolution of tens of meters is needed to characterise the urban heterogeneities. Spaceborne remote sensing meets the first and the second requirements but the Land Surface Temperature (LST) resolutions remain too rough…
IoT monitoring of urban tree ecosystem services: Possibilities and challenges
2020
Urban green infrastructure plays an increasingly significant role in sustainable urban development planning as it provides important regulating and cultural ecosystem services. Monitoring of such dynamic and complex systems requires technological solutions which provide easy data collection, processing, and utilization at affordable costs. To meet these challenges a pilot study was conducted using a network of wireless, low cost, and multiparameter monitoring devices, which operate using Internet of Things (IoT) technology, to provide real-time monitoring of regulatory ecosystem services in the form of meaningful indicators for both human health and environmental policies. The pilot study w…
Role of green coverings in mitigating heat island effects: an analysis of physical models
2013
Worldwide, governments are introducing several rules and standards in the aim of limiting the quantity of primary energy for air conditioning of buildings and supporting the use of renewable source of energy for generating thermal and electric energy to be utilized in buildings such as the European Directive on the Energy Performance of Buildings [1]. Along with these interventions, another important action takes currently place in the building sector, that is the introduction of passive structural components of the envelope, able to reduce the requirements of energy for air conditioning purposes. Among these building components, the so-called green roofs are becoming more and more interest…
Set up of a monitoring system for a preliminary evaluation of the Urban Heat Island in the town of Palermo
2008
Surface energy balance of urban areas depends on the thermal features of building materials, as well as the overall urban layout and various anthropogenic factors. In extended urban areas, all these factors give rise to the phenomenon known as Urban Heat Island (UHI). From the point of view of urban health, the occurring of UHI drastically changes the fluid dynamic interaction between the air and the city surface, often preventing the dispersion of gaseous pollutants. In the last years in fact, several studies have monitored the increasing trend of breathing diseases and allergies correlated with the presence of UHI. Nowadays, a rational design of the urban areas within large towns should t…
Mesures de la température et spatialisation de l’Ilot de Chaleur Urbain à Dijon
2015
The Territorial Climate Energy Plan (PCET) of the agglomeration of Dijon (Grand Dijon) includes ameasurement campaign (6 June to 28 September 2014). 50 Hobo proV2 thermometers were deployed. The selection of siteswas carried out so that the different types of urban environment (Oke, 2006) are documented. The Urban Heat Island (UHI)is discernible mainly at night, when radiative conditions are well established the day before. It is estimated to 1°C onaverage for the summer, 3-4°C during nights of fine weather. It reached 6°C during the warmest periods of the 2014 summer.A cool axis through the agglomeration shows that vegetation and water can sensibly mitigate the ICU effect.