Environmental design solutions for existing concrete flat roofs in low-cost housing to improve passive cooling in western Mexico

The development of real estate in Mexico has largely ruled out the comfort of users that focused on economic matters and made it difficult to make substantial progress in adopting measures to improve indoor environmental quality. Current research projects in Mexico found that roof construction in low-cost housing struggles to meet the requirements of the indoor climate. Passive cooling strategies are techniques to control heat gain and heat dissipation in buildings to maximise the comfort and health of building users while minimising energy use. Passive cooling systems recognize climate conditions and utilise renewable sources of energy such as the sun and wind to provide cooling and ventilation. Therefore, this study aims to develop a green and sustainable solution for existing concrete flat roofs with no major interventions and investments to save energy. The design of a passive device was tested to assess its effectiveness to protect flat roofs from shortwave radiation and to allow for heat dissipation in Mexican buildings. The study used a quantitative approach based on experiments and simulation tests to evaluate design efficiency. The results showed that a perforated device with an opening percentage of 88% and a cavity of 0.05m between the roof and the device provided effective protection. Also, the device with blinds of 45° showed lower operative temperatures within a range of mean values between 0.8°C and 0.9°C compared to a roof with a full shade cover in the hot and humid season. However, the perforated device with blinds of 90° in black colour delivered the best performance compared to other models and recorded a mean value of 1.13°C in the hot sub-humid season. The results revealed the efficiency of the proposed device that can be observed within different geometric configurations, surface properties as well as the use of the nocturnal radiative cooling potential in blocking solar radiation in Mexican buildings

Relative vulnerability to hurricane disturbance for endangered mammals in Mexico: a call for adaptation strategies under uncertainty

Most climate change vulnerability assessments of species focus on characterizing the degree to which species are likely to be affected by changes in mean climatic conditions. Yet, there has been little progress in the explicit assessment of species vulnerability to extreme climatic events (ECEs) which have the potential to cause substantial environmental disturbance and potentially catastrophic declines of wildlife populations. Using a trait-based approach, we assessed the relative vulnerability of populations of wild animal species to hurricanes, focusing on 25 terrestrial mammals at high risk of extinction in Mexico. Our assessment uses biological traits associated with heightened sensitivity (low vagility and territoriality) and low adaptive capacity (restricted diet and habitat specialization) in relation to their predicted exposure to hurricanes, based on records of occurrence of hurricanes in their geographical range over the past 45 years. We found that territoriality was present in most of the species assessed (n = 20) followed by habitat specialization (n = 6), low vagility (n = 6) and diet specialization (n = 3). Two subspecies of spider monkeys Ateles geoffroyi vellerosus and A. g. yucatanensis, two howler monkeys Alouatta pigra and Alouatta palliata mexicana and the silky anteater Cyclopes didactylus all emerged from this assessment as highly vulnerable to population declines from exposure to hurricanes. In the absence of any robust predictive framework for assessing risk to species from ECEs we suggest that the integration of data on hurricane exposure and species’ intrinsic biology, as presented here, represents a coherent and informative basis for risk evaluation and the design of possible mitigation strategies

Analysis of the social and environmental economic sustainability in the territory of Yucatan (Mexico)

This research focuses on the state of Yucatan, Mexico, and provides evidence of unsustainable performance of the local economy: the local economic structure and income distribution widens the gap between rich and poor households. A constructive policy towards sustainable development would place greater emphasis on productive restructuring the agricultural sector, road transport and electric power generation, in designing actions of technological change and sustainable natural resource management. An exhaustive hybrid environmental social accounting matrix (ESAM) and linear multipliers models are used to analyse the interactions of the local economy with the use of resources, the environment and income distributio