Human induced climate change is a widely acknowledged phenomenon whose future impacts are not yet fully understood, given the complexity and unpredictability of the global climate system and our interdependency with it. Due to the scope and potential implications of climate change, the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) established the Intergovernmental Panel on Climate Change (IPCC) in 1988. The IPCC does not conduct research itself but, instead, ‘it assesses the most recent scientific, technical and socio-economic information produced worldwide relevant to the understanding of climate change’ (Intergovernmental Panel on Climate Change, n.d.).
The scientific nature of the work reviewed by the IPCC and the methods employed for that revision are meant to provide a neutral perspective on the challenges and opportunities posed by climate change. However, the IPCC work is meant to create an impact in decision making as its reports are policy-relevant while avoiding a prescriptive approach/narrative. The body of work produced by the IPCC in the last 30 years has been the foundation for countries to develop their own strategies and supporting policies to better deal with climate change in harmony with their unique conditions (environmental, geographic, demographic, cultural, economic, etc.) and development targets.
The prevailing climate change scenarios point to toward rising global temperatures leading to warmer winters, hotter summers, generalized reduction of fresh water supplies due to the melting of mountain ice caps which feed rivers, and variations in rainfall patterns. It is also expected an increase in the frequency and intensity of extreme weather phenomenon such as flash flooding, hurricanes, tornados, etc. However, the impacts of those phenomenon will be uneven all over the planet and thus it is necessary for each country to develop its own strategies for climate change adaptation.
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The building industry is a very particular business because buildings are part of larger urban socioeconomic, cultural and political systems embedded in geographic regions with unique climate and weather patterns. Also, most of the existing build stock was designed for the climate that existed when they were built (best case scenarios) and in most cases are not apt to cope with current and future climates. Hence, it is important for the construction sector to develop locally appropriate adaptation strategies given that buildings have a long life span (30-50 years minimum) which means that new build stock will have to cope with future weather scenarios of climate change. It is important to make a distinction between new buildings and existing ones (retrofitting) since each would require different type of
interventions. A finer sub-division is also necessary depending upon build typology and end use because energy requirements, occupancy patterns, and the intensity of resources consumption vary as a function of those; e.g. vertical or horizontal housing (single family, multi family, detached housing, row housing), commercial buildings, factories, hotels, offices, etc. this sub classification is especially relevant for sectorial policy making.
As mentioned before, current efforts in sustainable construction in Mexico have focussed on GHG emissions reductions in the social housing sector through the Green Mortgage
programme (introduction and dissemination of eco-technologies for the social housing sector) and, most recently, through the housing NAMA, incorporating energy efficiency, thermal comfort, and water consumption with a technical approach supported by the Passivhaus Institute through the whole building approach.
On the other hand, international experience shows that countries such as the UK (Gething, 2010), and Australia (Australian Sustainable Built Environment Council, 2012) have
developed general adaptation strategies focused on three main aspects:
• Designing for comfort. Building design, open and urban design, thermal comfort (heating and cooling)
• Construction. Structural stability above and below ground, weather proofing, detailing and construction materials
• Water managing. Water conservation (efficiency), drainage and flooding prevention/management
From an architectural perspective, design for comfort, and construction are closely intertwined given that both aspects are interdependent since architectural design and construction materials selection will impact on thermal comfort and the overall energy efficiency of a building (orientation, window sizing, materials specification, etc.). Water management on the other hand, is quite complex and strongly depends on local water supply, distribution, and management at regional and urban level and all the way down to
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building level in which efficiency can be achieved through the implementation of water saving/efficient fixtures (toilet, shower, zinc, etc.). Alternatively, strategies such as rain water harvesting, are strongly dependent on rain availability, which varies by region.
From an economic perspective it is also widely acknowledged that the implementation of mechanisms that increase resilience are more cost-effective when implemented early (through planning, design, or policy) than through subsequent retrofit interventions
(Australian Sustainable Built Environment Council, 2012, p. 16). This is particularly relevant for the Mexican context with a growing population that is expected not to stabilize until 2050. With increasing urbanization rates that are expected to reach 83% of the population by 2030 with almost 50% of that population living in poverty. Hence, the relevance of developing low- cost energy efficient and climate change resilient design alternatives for the Mexican low income social housing.
Recent research in different geographic locations such as Mexicali City, Mexico (Gutierrez, et al., 2014), San Juan City, Argentina (Alvarez, et al., 2017) and from an evolutionary perspective of bioclimatism (Nguyen & Reiter, 2017) had focussed on testing the present and future effectiveness of bioclimatic design strategies as a cost-effective and locally appropriate climate change adaptation strategy for the construction sector (Beccali, et al., 2018). This is particularly relevant for naturally ventilated buildings whose thermal comfort parameters are closely related to outdoor temperatures and for which a closer look at present weather conditions as wells as future weather scenarios can provide with general strategies that might generate thermal comfort climate change resilience for the housing sector.