Green Roofs in Hot Arid Climates

Green roofs are living systems designed to provide multiple ecological and resource benefits. Municipalities in the United States and abroad are using green roofs to enhance urban sustainability. Yet, they have not been widely researched in arid climates. This research fills that gap in our knowledge by using a case-control research design to quantify the performance of green roofs in hot arid urban climates. The green roof study is a ten-month (from June 2015 – March 2016) pilot on the Design School roof at ASU to quantify the ecological services of green roofs in hot arid environments. I examine how green roofs impact 1) urban heat islands (a key component in air pollution and increased energy consumption), 2) stormwater, and 3) ecological health and biodiversity. The anticipated outcomes include 1) reducing urban heat islands during the daytime, 2) reductions in daytime heating will likely contribute to lowered energy cost at the time of day it is the most expensive, 3) reduction in stormwater runoff, and 4) providing enhanced ecological habitat over conventional roof surfaces. The outcomes of this project will provide researchers and practitioners a better understanding of the opportunities and obstacles to using green roofs in desert climates to address urban heat islands, energy consumption, stormwater flooding, and biodiversity.