Our urban climate research team is investigating how land cover traits, such as vegetation and building density, affect the local climate, and how the local climate subsequently influences quality of life.Cities are often warmer than their rural surroundings, a phenomenon known as the urban heat island effect. High building density and paved surfaces cause cities to retain more heat than open, natural areas.

Virtually every city experiences a heat island effect, but the larger the city, the larger the effect. Typically, cities can be 3 to 7 degrees warmer at night and 1 to 3 degrees warmer in the day, as compared to rural areas. Clear and calm weather conditions can make the temperatures even higher. Heat islands can have significant impacts on human health, energy demands for heating and cooling, local ecosystems, and the water cycle.

We quantified Madison’s heat island effect with 150 temperature and humidity sensors installed on streetlights and utility poles across the metropolitan area.* Since March of 2012, the sensors have continuously recorded local temperature and humidity every 15 minutes.  The following questions guide our heat island research.

• How and why do temperature and humidity vary across the Madison region?
• What effects does the urban climate have on human health, quality of life, local ecosystems, and the water cycle?
• How can weather forecasting be improved by using information about the patterns and behavior of the Madison UHI?

Lead Scientists: Jason Schatz (alumnus), Chris Kucharik, Meirah Williamson

*We partnered with local governments and utilities to make this research possible: Madison Gas & Electric, Alliant Energy, the City of Madison, Madison Parks, Sun Prairie Utilities, Waunakee Utilities, the UW-Madison Arboretum, the City of Fitchburg, and Dane County.