This paper analyses Seville’s surface urban heat island (SUHI) phenomenon, comparing spatial and temporal patterns of land surface temperature (LST) during July 1987, 2000 and 2017. Landsat data captured throughout three July months were analyzed for the different years, techniques of geographic information systems, ecological variables and geospatial approaches and used to carry out the analysis. The results indicate that from 1987 to 2017, the averaged LST has increased by 9.1 °C in the studied area. The urban areas are colder than their surroundings, suggesting the role of baresoil and cultivated land in the reversal of the SUHI phenomenon. The results show that a fraction of green space has a high unstandardized coefficient (β) through the three time periods. A decreasing trend is also observed in the standardized β “fraction of impervious surface” in the three time periods. The linear regression analysis shows a negative relationship of mean LST with impervious surface fraction due to the presence of shadows projected by buildings, and a positive relationship with green space fraction caused by the influence of baresoil and cultivated land that inverts the LST behavior pattern. The study concludes that there is a need to implement SUHI mitigation strategies during the initial phases of engineering projects where the origin of this problem can be acted upon, since the process of creating streets and public space offers a valuable opportunity to restore the environmental quality and diminish the effects generated by climate change.

Recent research in the field of building materials has led to focus on phase change materials (PCMs). These materials allow the adjustment between energy demand and supply of the climate control systems by storing. Experiments were carried out to investigate the feasibility of using heat storage materials (with PCM addition), placed as one of the flooring layers over radiant floor heating system. In this study, paraffin wax ASTM D 87 (MP 53-57ºC) has been added directly during the mixing stage as a PCM, used in mixtures with various contents of paraffin (0,75%, 1,5%, 2,5% with respect to the weight of cement. It was also produced a none paraffin content specimen) and 0,45 water/cement ratio cement mortar. The experiments have been carried out inside of a completely isolated thermal box in which a heating system has been arranged and a measurement equipment for the temperature record. Every experiment consist on four stages that complete the full process of charging the energy storage mortar specimens, by heating the system fluid, and its subsequent progressive discharge after the heating source is off. While testing each specimen different temperatures have been collected: environment temperature outside the thermal box, indoor air temperature, surface temperature of each specimen with the corresponding PCM content, inlet and outlet fluid temperature inside heating system pipe. After carrying out every specimen test it is notice that PCM addition to cement mortar floor layer over the heating sys tem is effective, the more proportion of paraffin added the most appropriate, since it takes a longer period of time to release storage heat during the phase change. Paraffin is an organic material easy to add to the cement mortar porous composition not adversely affecting material resistance, and it has the power to store energy as latent heat by phase changing.

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