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The urban heat island (UHI) effect describes the phenomenon whereby cities are generally warmer than surrounding rural areas. UHI increases energy consumption, air and water pollution, and, in general, reduces the urban life quality. Consequently, UHI mitigation and adaptation is a priority in many cities around the world. Although the UHI effect can be perceived in the Aburra Valley, where the city of Medellin is located, it has been studied superficially and so far there are no prevention or mitigation measures at the regional scale. This paper presents an estimation of the UHI in the metropolitan area of the Aburra Valley. The UHI was estimated using Landsat TM, ETM+ and OLI/TIRS images acquired between 1986 and 2016. Results showed that the average surface temperature in the urban area was 4.81 oC warmer than in the rural surroundings.

UAV photogrammetry has simplified the measurement of the terrain's surface; however, the accuracy of the method is still a matter of research as it depends on multiple factors such as the UAV employed and the decisions made by the user during information acquisition and processing. This chapter analyses the accuracy of 27 digital elevation models (DEMs) built from the data acquired with a DJI Phantom 3 drone, which was flown at different heights and trajectories in a case study in the Colombian Department of Antioquia. The statistical analysis confirmed that the use of ground control points (GCPs) is fundamental to increase the accuracy of the map products. It also showed that accuracy, understood as the comparison between the coordinates of points measured in the field (CPs) with their corresponding values estimated in the orthophotomosaics, depends on the number of CPs and their location. An insufficient number of CPs or an inadequate distribution, for instance all or most of them located in a single land cover, will cause the accuracy to be overestimated.

One of the most commonly used forms of educational evaluation is by means of student surveys. In Colombia, as in all countries of Latin America, student course evaluations in higher education remain focused on teaching performance, while the results of these instruments are frequently used as an indicator (and in some cases the only indicator) of quality and effectiveness of both undergraduate and postgraduate programmes. This article argues that the teacher-centred evaluation provides insufficient information to improve the quality of higher education. Therefore, a process-based evaluation model (PBEM) is proposed for a Colombian university offering engineering programmes. The PBEM is intended to provide reliable information on teaching effectiveness, but also about other factors influencing teaching and learning such as course design. The PBEM was designed in accordance with the EIA University’s pedagogical model, which encompasses competencies, values, and key areas of transversal learning. The...

Thermal anomalies in built environments, known as Urban Heat Islands (UHI), are studied with satellite-derived data. However, this information is insufficient to examine regions such as the Aburra Valley, where the city of Medellin is located. In this valley, atmospheric interferences are common and the rugged terrain influences the amount of solar radiation reaching the surface, which hinders the analysis of the UHI. Unmanned Aerial Vehicles (UAVs) can be used to obtain the Land Surface Temperature (LST) at a time and location that is more convenient. In this project, a UAV was equipped with a thermal sensor to collect data on natural (ground vegetation and trees) and artificial (concrete, asphalt, and clay roof tiles) land cover types in Medellin, Colombia. The thermal information provided by the drone overcame the limitations of the satellite-derived data in terms of spatial, temporal, and radiometric resolution. This data enabled the study of specific land-cover types in different urban contexts, especially the influence of vegetation on LST. The findings suggested that the distribution of trees is crucial for UHI mitigation. Tree shading reduced the surface temperature of asphalt in average by 12 °C and by 5.7 °C for concrete. In addition, the presence of trees alongside streets reduced the maximum surface temperature of asphalt by 22.4 °C in the same neighborhood. These results contributed to the understanding of the influence of urban development on Medellin’s temperature.

Resumen El ambiente térmico en una edificación influye en la salud, el bienestar y la productividad de las personas, así como en el consumo energético. La importancia del confort térmico en las edificaciones se reconoce desde hace décadas, no obstante, este aspecto es aún incipiente en la industria de la construcción colombiana, sobre todo en proyectos de vivienda. En esta investigación se analizó el desempeño térmico de tres tipos de vivienda comunes en la ciudad de Medellín. Para ello se calculó la temperatura operativa, el voto medio estimado (PMV) y el porcentaje estimado de insatisfechos (PPD), de acuerdo con la norma ISO 7730:2005. Los resultados mostraron que la inercia térmica de dos de los tres tipos de vivienda examinados no es suficiente para ofrecer un confort térmico adecuado, a pesar del clima templado del Valle de Aburrá. Estos resultados alertan sobre la vulnerabilidad de la población urbana en Colombia ante fluctuaciones extremas de temperatura. Abstract The indoor thermal environment of buildings influences people's health, well-being and productivity, as well as energy consumption. The importance of thermal comfort in buildings has been recognized for decades. However, this aspect is still incipient in the Colombian construction industry, especially in housing projects. In this research, the thermal performance of three common housing types in the city of Medellin was analyzed. To do this, the operative temperature, the predicted mean vote (PMV) and the predicted percentage of dissatisfied (PPD) were calculated in accordance with ISO 7730:2005. The results showed that the thermal inertia of two of the three types of housing examined was insufficient to offer adequate thermal conditions, despite the temperate climate of the Aburra Valley. These results warn about the vulnerability of urban population in Colombia to extreme temperature fluctuations. Resumo O ambiente térmico em uma construção influencia na saúde, no bem-estar e na produtividade das pessoas, bem como no consumo energético. A importância do conforto térmico nas edificações é reconhecida há décadas, não obstante, esse aspecto ainda é incipiente na indústria da construção colombiana, sobretudo em projetos de habitação. Nesta pesquisa, o desempenho térmico de três tipos de habitação comuns na cidade de Medellín foi analisado. Para isso, calculou-se a temperatura operativa, o voto médio estimado (PMV) e a porcentagem estimada de insatisfeitos (PPD), de acordo com a norma ISO 7730:2005. Os resultados mostraram que a inércia térmica de dois dos três tipos de habitação examinados não é suficiente para oferecer um conforto térmico adequado, apesar do clima ameno do Valle de Aburrá. Esses resultados alertam sobre a vulnerabilidade da população urbana na Colômbia ante oscilações extremas de temperatura.

Environmental evaluation procedures like SEA have become a key component in development planning and decision making. With the aim to anticipate and mitigate its possible effects, the necessity for a better understanding of the environmental consequences created by the implementation of policies, plans and strategic actions has been recognized. The knowledge of environmental mechanisms has been developed gradually, through wide participation of stakeholders and the consideration of new evaluation criteria such as cultural impacts.