UCSD Study Finds Some Urban Neighborhoods Are Hotter Than Others
A pair of new studies out of UC San Diego finds that minority neighborhoods in the nation’s cities are significantly hotter than white neighborhoods and cities tend to be hotter than rural areas.
The research published in the journal Earth’s Future looked at more than a thousand counties in the United States.
It found that Black, Hispanic and Asian neighborhoods experience more heat in their neighborhoods than predominantly white neighborhoods.
And it is not just because white neighborhoods are more affluent.
“Even when you adjust for income, so now say, I’m going to look at neighborhoods with different racial and ethnic compositions that have the same average household income and you still see this race and ethnicity gradient," said Jennifer Burney, the endowed chair in Global Climate Policy and Research at the School of Global Policy and Strategy.
"So even when you’re thinking about normalizing out incomes, putting that bit equal, you still see this race gradient."
Burney says there are many factors that explain the temperature difference, but she said it is consistent across the country. The disparity exists in cities like New York, Minneapolis, and Chicago, among others.
“We were nevertheless pretty surprised to see it was ubiquitous across the United States. In places with very different geographies and histories and racial and ethnic compositions,” said Burney.
The hotter neighborhoods are typically denser and have fewer trees.
When researchers compared neighborhoods with similar economic means, the racial minority neighborhoods were still about seven degrees hotter.
Post Doctoral Researcher Susanna Benz said the difference in temperature has an impact on productivity, school test scores, premature births, and overall health linked to more intense heat.
That takes on even more importance as the climate warms.
In a complementary study published in the journal, Environmental Research Letters, Benz and Burney expanded their analysis on a global scale.
They found that cities are typically hotter than the rural areas around them, unlike San Diego where the city is cooler because it is close to the coast and surrounded by hotter desert climates.
“Seventy-five percent of people living in these cities live in these so-called urban heat islands,” Benz said. “So really 75 percent of urban inhabitants experience this urban heat at day and at night.”
The study concluded that vegetation and urban density are the two biggest drives of urban warming.
The research suggests urban planners will have to change the way they think about designing cities to make them more resilient to climate change.