Measuring and Mitigating Urban Warming in a Northern Metropolitan Area
Department of Forest Resources
University of Minnesota
TCS Building 240
In the United States and much of the rest of the world, cities are warming at twice the rate of outlying rural areas and the planet as a whole. While the warming can be partially attributed to global climate change, it only accounts for a small fraction of the overall warming. More significant is the contribution of the built environment, which results from land use change whereby the natural background landscape is replaced by the gray infrastructure of cities.
With a population of more than 3.75 million over a seven-county area, the Twin Cities Metropolitan Area is used as an example of the challenges of measuring and mitigating urban warming and maintaining a sustainable environment for its citizens, economy, and urban ecosystems. Data from a dense network of temperature sensors is used to characterize the physical behavior of urban warming.
The economic, environmental, and human toll of urban warming in the Twin Cities is far-reaching and significant. The additional energy necessary to cool buildings burdened by urban warming amounts to tens of millions of dollars annually. Ground-level ozone, exacerbated by the additional warming has been directly linked to harming the cardiovascular health of Twin Cities residents, and the presence of urban warming has increased the population of invasive plants and animals, along with altering the mating habits of birds and the survival of pollinators. Some of these Impacts, especially social vulnerability factors that disproportionately impact underrepresented groups, and mitigation strategies are discussed.