29 July 2019

Evolution of Extreme Heat Risk in Cities: Interacting implications of climate change, population dynamics, and urban heat mitigation

Urban micro-climate modeling is used to investigate future exposure to heat extremes and associated energy demands at neighborhood scale.

Science

High-resolution regional climate simulations coupled with a satellite-driven urban canopy model are used to investigate the interacting effects of climate change, population growth, and urban heat mitigation measures on exposure to extreme heat events and associated energy demands.

Impact

This study sheds light on the relative importance of climate change and population dynamics in driving the evolution of extreme heat risks and associated energy demands in the cities across California by the mid-century as well as  the potential for heat mitigation measures to push them back.

Summary

Climate change projections suggest that, over the next few decades, extreme heat events will become more frequent and their impacts can be especially large in cities due to a high concentration of people and preexisting urban heat islands (UHIs).  Here we use California as a testbed where we employ a suite of high-resolution future regional climate simulations coupled with a satellite-driven urban canopy model and a spatially explicit population projection to investigate the interacting effects of climate change, population growth, and urban heat mitigation measures, such as cool roofs, on exposure to extreme heat events. We find that climate change and population growth reinforce one another to drive substantial increases in future exposure to heat extremes and associated energy demands for cooling buildings.  We further find that heat mitigation measure such as widespread adoption of cool roofs can substantially reduce these impacts in urban areas.

Contact
Andrew D. Jones
Lawrence Berkeley National Laboratory