Paving the Way for Climate-Resilient Infrastructure - UN CC:Learn

Chapter 6: Internalization of Climate Risks in the Context of Planning and Urban DevelopmentPART IITechnicalPresentation 1Figure 6.7: Population growth in Mexico City in the last century (population in thousands [x 1000])What a Country ShouldThink About andThen Do to AddressClimate Change andInfrastructure RisksTechnicalPresentation 2Internalization ofClimate Risks in theContext of Planningand Urban DevelopmentSource: Aguilar (2004).Other problems also affect Mexico City’s water supply: limited options for importing water from otherbasins, water leaks (25–30 percent leakage), high per capita consumption, imbalances in water consumptionbetween social groups, water quality, future increases in demand, poor collection service, and aninadequate legal framework. In addition, Mexico City has problems protecting the main area of rechargeof the aquifer. This is a forested area in the South and West part of the Federal District declared protectedarea. However, local authorities have had problems controlling illegal and informal settlements in thatarea jeopardizing the recharge of the vital aquifer for Mexico City (Schteingart y Salazar, 2002, Ruiz-Gomez,2006). Recent studies have documented other threats to the protected area. Fires threaten the stability ofthe forest ecosystem (Vazquez (2010) documents 2,772 fires between 2008 and 2010 in this area). Acidrain caused by air pollution in Mexico City also weakens the forest ecosystem, making it vulnerable to theattack of pests (Bauer and Hernandez-Tejeda, 2007). The loss of forest in this area will dramatically affectthe recharge of the aquifer.The impacts of climate change are predicted to further exacerbate Mexico City’s water problems. Theapplication of models to analyse climate change and water supply for Mexico City show that water availabilitycould decrease by at least 10-16 percent (see Figure 6.8). The actual impact of climate change willlikely be even higher due to the monthly distribution of changes, including more intense periods of rain,minor infiltration and increased erosion. The scenarios also show a potential increase in temperatureduring the dry season. This would likely aggravate ozone pollution in Mexico City and the number andintensity of fires in the forest area south of Mexico City, accelerating the death of trees and further compromisingthe recharge of the aquifer mentioned above. Climate change will increase the demand of water inthe urban area at the same time.TechnicalPresentation 3A Framework forRisk Assessmentand Risk-InformedDecision-Making forInfrastructureDevelopmentTechnicalPresentation 4Probabilistic RiskModeling: BasicPrinciples andApplicationsTechnicalPresentation 5An Economic Frameworkfor Evaluating ClimateProofing Investmentson InfrastructureTechnicalPresentation 6Supporting ElSalvador to ReduceInfrastructure Riskswithin a Green, Low-Emission and Climate-Resilient Frameworkfor DevelopmentPaving the Way for Climate-Resilient Infrastructure: Conference Proceedings 75