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Understanding the synergies between the Urban Heat Island (ICU) phenomenon and one of the extreme climatic events such as heat waves has become one of the great challenges of society that seeks to improve the quality of life. In this research, the Terrestrial Surface Temperature (TST) and the Urban Surface Heat Island (ICUS) have been determined using Sentinel-3 images of the city of Granada (Spain) during the months of July and August of the years 2019 and 2020. The purpose is to determine the possible synergies between both phenomena in an area classified as highly vulnerable to the effects of climate change. Using the Data Panel statistical analysis method, multivariate relationships were obtained during the heat wave periods. The results obtained, in line with previous research, indicate that TST and ICUS are intensified under heat wave conditions (Daytime: TST=2.2 °C and ICUS=0.2 °C; Nighttime: TST=4.4 °C and ICUS= 0.3 °C) and there are relationships between ICUS and wind direction and solar radiation that intensify in periods of heat wave. © 2022, Universidad Politecnica de Valencia.. All rights reserved.

La recerca de noves tècniques que permetin determinar de manera econòmica i precisa el fenomen d’alteració de clima urbà anomenat Illa de Calor Urbana (ICU) s’ha convertit en un dels grans reptes de la societat. El seu coneixement sobre les urbs permetria la implantació de mesures de mitigació i resiliència que tendeixin a minimitzar-ne els efectes i el cost econòmic que comporta. En aquesta investigació, s'ha determinat la Temperatura de la Superfície Terrestre (TST) i la ICU mitjançant imatges satel·litàries Sentinel 3 de les vuit capitals d’Andalusia (Espanya) durant l’any 2020. Aquestes s’ubiquen en una zona qualificada com d’alta vulnerabilitat als efectes del canvi climàtic, el que unit a l’ús de zones climàtiques locals (ZCL) permet que els resultats puguin ser extrapolats a altres ciutats amb les mateixes tipologies de zones climàtiques. Els resultats obtinguts indiquen que durant el matí es produeix a les ciutats estudiades una illa de refredament urbà de temperatura mitjana -0,76 ºC i durant la nit una ICU de temperatura mitjana 1,29 ºC. Ambdues presenten majors intensitats a les ZCL compactes de mitjana i baixa densitat en contraposició amb les ZCL obertes i industrials. La variabilitat estacional de la ICU diürna s’intensifica durant l’estiu i l’hivern i la nocturna durant l’hivern i la tardor. Es comprova l’existència de relacions diürnes negatives significatives al 99% (p

This research was funded by the State Research Agency (AEI) of Spain and the European Regional Development Funds (ERDF), under project: PID2019-108761RB-I00., The need to tackle the urban heat island effect demands the implementation of cool surfaces as a mitigation strategy. This study comprehensively reviews the evolution of this research field from a materials perspective. It provides a bibliometric analysis of the relevant literature using the SciMAT software processing of bibliographic records from 1995 to 2020, for the evolution of cool surfaces. The results obtained show an increased interest in the field from 2011 to 2020, particularly for roof applications, and present the scientific evolution of reflective materials. According to the materials dimension adopted by the development of the research field, the study is refined from a bibliometric analysis of 982 selected records for the analysis of five themes: (i) Pigments; (ii) Phase change materials; (iii) Retroreflective materials; (iv) Ceramic materials; and (v) Glass. These materials present promising results in terms of their solar reflectance performances in the mitigation of the urban heat island phenomenon. At the end of this review, recommendations for future studies are provided for the creation of economic and environmentally friendly materials based on waste glass recycling. This study represents a valuable contribution that provides a scientific background with regard to cool surfaces from a materials perspective for future investigations., State Research Agency (AEI) of Spain, European Commission PID2019-108761RB-I00

Interstitial condensation is a phenomenon that occurs when, somewhere inside a construction element, a pressure equal to or greater than the saturation pressure is reached. At this time, condensation will occur inside the element, producing interstitial condensation. This phenomenon occurs mainly in the winter. This type of condensation produces various problems, such as the deterioration of materials, humidity, reduced comfort conditions inside the home and health problems. Further, the urban heat island effect means that due to different factors — building materials, green areas, volumes— temperatures are not homogeneous in all areas of the city. This effect makes the same building in different areas behave differently. This research aimed to analyse the influence of the urban heat island effect on interstitial conditions in a temperate oceanic climate. This study was carried out through a case study consisting of a typical house, with three different constructive solutions, located in four representative city points. The city where the experiment was carried out corresponds to Puerto Montt, in the south of Chile. Puerto Montt has a temperate oceanic climate with mild summers and long winters. The research results will be helpful when selecting different constructive solutions for the thermal envelope in cities with temperate oceanic climates.

In recent years there has been an increase in the number of extreme weather events that lead to higher mortality, such as heat waves. This study carries out a new investigation that integrates the environmental quality parameters—the Surface Urban Heat Island (SUHI) and the Terrestrial Surface Temperature (LST)—during these periods of high temperatures and compares them with normal periods. The study of the relationship between these variables will allow improving the quality of life through new mitigation measures that will minimize the effects of climate change in urban areas. This study analyzes eight cities in the south of Spain (Andalusia) to assess environmental quality through gases SO2, NO2, CO, O3 and aerosols, obtained through Sentinel-5P satellite images, and the LST and SUHI obtained through Sentinel-3 images. Next, the results of periods of heat waves are compared with periods of normal environmental conditions during the summers of the years 2020 and 2021. The objective is to determine the possible impact of heat waves on environmental quality, as well as on the LST and SUHI of the investigated cities, which are located in an area identified as highly vulnerable to the effects of global warming. During the period of the heat wave and compared to the periods without a heat wave, a variety of environmental pollutants was found: SO2 (+165%), NO2 (+24%), CO (+8%), O3 (−4%) and aerosols (+193%). Both the LST and the SUHI suffered an average increase of 2.8 K. The results of this document can help to establish pollutant reduction mechanisms in periods prior to heat waves. This could minimize major effects on the population and provide sustainable development. © 2022 by the authors.

The growth of the population in cities and the increase in the use of construction materials caused the cities' internal temperature to increase, producing the effect known as urban heat island. For this reason, there is scientific interest in mitigation methods of adaptation to this effect in the construction area. The main objective of this research is to analyse the scientific articles published from 1990 to 2019 that relate to pavements and the urban heat island phenomenon, using the SciMAT tool for bibliometric analysis to evaluate the general evolution of this area of science. The analysis was carried out on 107 articles, and a clear evolution was found in the research methodologies of studies of pavements in urban heat island conditions. Until 2008, 73% used field or controlled field experiments. In 2019, this ratio had decreased to 36%, while investigations with laboratory experiments were the most prevalent, at 37% of all investigations. In recent years, interdisciplinary research has focused on the issues of mitigating the effects of urban heat islands together with improving the energy performance of dwellings. © 2020 Elsevier B.V.