In 1995, Chicago experienced an extreme heat event that led to the deaths of several hundred people over the course of five days. Recognizing climate change will affect extreme heat events among many other weather events, Chicago decided to conduct a vulnerability assessment to better understand the threat. Chicago conducted a vulnerability assessment that projected future expected temperatures and estimated the magnitude of threat to future heat related mortality. In anticipation of these future threats, Chicago adopted a comprehensive Climate Change Action Plan. The city’s first priority under the Chicago Climate Action Plan: Adaptation Strategy Report is to adapt to extreme heat events.
Chicago’s approach assessed vulnerability to extreme heat and promoted resiliency and adaptation actions to reduce climate risk. Specifically, Chicago is promoting resiliency through emergency response procedures, specifically including it as a specific criterion within the county's (Cook County) Hazard Mitigation Plan and identifying that its Extreme Weather Operations Plans have scalability to deal with projected changes.
In order to adapt to future extreme heat events, Chicago is identifying urban heat areas ('heat islands') of concern and then adopting heat island reduction strategies through a variety of municipal programs including: building codes and green infrastructure projects. These green infrastructure strategies provide Chicago with mutual benefits including increasing extreme heat emergency preparedness and improving stormwater management for extreme precipitation events.