A University of Wisconsin researcher is studying how urban land patterns can reduce residents’ exposure to extreme weather events

A University of Wyoming researcher was part of a recent study that examined how changes in urban land and population might affect future residents’ exposure to extreme weather events at the end of the 21st century.

Melissa Bukowski, an associate professor at the University of Wisconsin’s Haub School of Environment and Natural Resources, teamed up with Jing Gao, an assistant professor of geospatial data science at the University of Delaware, to look at urban areas — including large and small cities — across the world. Continental United States, with different development densities and in different climate zones.

Intuitively, when an extreme weather event hits a city, the larger the city’s population, the more people are likely to be affected. Currently, 83% of the US population lives in urban areas, according to the US Census. This number is expected to grow over the coming decades, making urban climate resilience extraordinarily important. As a result, many people perceive that increasing city sizes make extreme weather conditions worse for the people who live there.

However, cities are designed and built by people. Therefore, it stands to reason that if some land development approaches increase residents’ exposure to extreme weather conditions, others may hold the potential to mitigate or even reduce residents’ exposure as climate changes over the coming decades.

“This finding contradicts the common belief that population exposure to extreme events increases when urban land area increases,” says Bukowski, who is also the Dericho Professor at the University of Wisconsin School of Computing. “Our work suggests that development patterns can be identified that can reduce exposure, or at least do not double exposure, to extreme weather events, and in the long term, these patterns can help guide more resilient development in the face of increasing instances of extreme weather.”

Bukowski was the second author of a paper titled “Urban land patterns can mitigate population vulnerability to climate extremes during the 21st century” which was published on October 26 in Nature Communications, an open-access, interdisciplinary journal dedicated to publishing high-quality research in all fields. . Fields of biological, health, physical, chemical, earth, social, mathematical, applied and engineering sciences.

Gao, who is also a resident faculty member at the Data Science Institute at the University of Delaware, was the lead author of the study. During the study, which was conducted from late 2020 through August 2022, Bukowski was a research scientist at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado.

The two used a data-driven model developed by Gao to predict — based on development trends observed over the past 40 years — how urban areas across the country would grow by 2100. The research team looked at how these changes in urban land would affect the weather. Extremes, including heat waves, cold waves, heavy rains, and severe thunderstorms. They then analyzed how many people would be exposed to these extreme conditions under different climate and urban development conditions at the end of the century.

Computer simulations conducted by the research team showed that at the end of the 21st century, how a city is laid out or spatially organized – often called urban land pattern – has the potential to reduce residents’ exposure to extreme weather events in the future, even for heat. Waves at very high rates of urbanization. Moreover, how the urban landscape is designed—how buildings are grouped or dispersed and how they fit into the surrounding environment—seems to matter more than just the size of the city.

Even while climate change increases residents’ vulnerability, the two found that this applies to all cities—from large urban areas, like New York City, to small cities in rural contexts, like Newark and Del.

“Regardless of the size of a city, well-planned urban land patterns can reduce residents’ exposure to extreme weather extremes,” says Gao. “In other words, cities, large and small, can reduce risks from extreme weather events by better arranging the development of their land.”

“We found that the spatial pattern of urban development on the landscape can mitigate the exposure of people living in urban areas to extreme weather events, including extreme heat events,” Bukowski adds.

The study findings differ from current common perceptions from the existing research literature in this area which has focused almost exclusively on reducing the amount of urban land development.

In turn, the new findings of this research encourage researchers and practitioners from a wide range of related fields to reconsider how cities are designed and built so that cities are in harmony with their regional natural surroundings and more resilient to potential long-term climate risks. Being.

Gao likens the effects of climate change and urban land patterns on the risk of extreme weather to the effects of a person’s diet and activity level on the risk of health problems. Properly designed urban land patterns are like physical exercise that counteracts poor dietary choices, she says, contributing to a reduced risk of disease while helping a person become fitter overall.

“Carefully designed urban land patterns cannot completely eliminate residents’ increased exposure to extreme weather events caused by climate change, but they can lead to a measurable reduction in increased risk,” says Gao.

The two are working to identify specific characteristics about the city’s spatial arrangement that could make it more – or less – resilient to future climate extremes. Identifying these patterns can help guide more sustainable development in the face of increasing instances of extreme weather. Through their efforts, Bukowski and Gao hope to provide actionable suggestions on how to design and build urban areas that reduce their residents’ exposure to extreme weather events over the long term.

Gao and Bukowski stress that these characteristics are likely to vary from one region to another, now and with climate change. For example, what might work in arid Phoenix, Arizona, may not work in humid New Orleans, Louisiana. Likewise, as climate conditions evolve, what works today in a city may differ from what works in the same city. In the future.

According to the paper, future research will investigate the mechanisms that lead to reduced vulnerability to climate change. These include physical factors—changes in evaporation, albedo, and sea breezes—and population and territory dynamics, including crowd development and migration.

“Ultimately, we want our work to directly benefit urban design and planning efforts, and provide insights and tools for decision-makers to impact long-term social and environmental well-being at scale,” Bukowski says. “But first, we need to identify development patterns that can improve cities’ resilience to climate change in the long term. We will continue to cooperate in the future.”

The current study was funded by the National Science Foundation, NCAR and the US Department of Energy.