Linking climate change to urban planning through vulnerability assessment: The case of two cities at the Mexico-US border

There is increasing evidence that climate change impacts have been particularly critical in the case of heat waves during the last years. Many cities around the globe have been affected by heat waves and their cascading effects, threatening public health and urban life and disrupting services and infrastructure. Unfortunately, cities in developing countries are not paying attention to heatwaves' impacts. This is the case in Mexico. Although there are studies on extreme heat exposure, there are no vulnerability assessments. The central research question of our study is the analysis of social vulnerability to extreme temperature and heatwaves in two Mexican cities at the U.S.- Mexico border, Tijuana, and Mexicali. Our results show that urban planning and state and municipal development policies in both cities have neglected the impact of heat waves despite their increasing frequency, intensity, and duration in the last two decades. The results also show significant differences in exposure, sensitivity, and adaptive capacity to extreme temperatures within each city. Areas with higher vulnerability in both cities are informal settlements and low-income neighborhoods. This information can support local governments in making sound use of scarce resources to create efficient responses to current impacts and future risks of climate change. •Risk of heat extremes in cities.•Difference in vulnerability within the city.•Neglected attention to heat extreme events in urban development plans.•Urgent need to adapt.