Urban Heat Island Effect
Urban heat island effect occurs when city temperatures run higher than those in rural areas because growing numbers of buildings have supplanted vegetation and trees, while human activity itself generates heat.

Macalester students are driving the clean-energy future

Alese Colehour '09
Minnetonka, Minnesota
Biology

What would you do with $10,000 from the U.S. Environmental Protection Agency? I installed a 1,600 square feet of green roof. A green roof is a planted space on a man-made structure. There are various types of green roofs, but they are all built by laying down careful waterproofing followed by drainage layers, spreading a growing medium and planting seeds. A green roof has potential to reduce "urban heat island effect," save heating and cooling costs and reduce storm water runoff.

Studies show that green roofing can double the lifetime of a roof's membrane and can even uptake particles and C02 from the atmosphere. This has enormous potential for urban areas like St. Paul.

A team of students from Macalester Conservation and Renewable Energy Society (MacCARES) wrote a grant proposal to the EPA for $10,000 through a campus sustainability competition, and we were one of the two liberal arts colleges to receive a grant. We strengthened connections Macalester already had with local businesses and forged some new and valuable partnerships. The Green Institute and Green Roofs for Healthy Cities were especially important.

Undertaking this project was a huge challenge. I learned how to be a project manager, community organizer, student leader and independent researcher. I also learned this type of activism is not just about the final result; it's also about the process of involving community partners and inspiring others to take action. I have had at least a dozen people ranging from students at the other colleges to members of the Algerian parliament contact me to ask about installing their own green roofs.