Poorer communities of color in Los Angeles have fewer trees, and as a result, less shade.
"The lack of tree canopy has many...public health effects, it's a public health crisis, really," said Ariel Lew Ai Le Whitson, the director of education and community at Tree People, an environmental nonprofit organization.
Less access to green spaces can cause "huge mental and physical issues" in communities, Whitson said.
She said green spaces can help people with mental health issues, but the biggest issue for her is urban heat.
Some studies show trees can cool air temperature by as much as 10% and surface temperatures by up to 45 degrees.
"Which is an incredible stat," Whitson said.
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For nearly two years, National Geographic environment Reporter Alejandra Borunda has been researching the shade divide in Los Angeles. Her findings appear in July's issue of National Geographic.
Borunda and her team drove along Vermont Avenue from South Los Angeles to Los Feliz and noted the stark differences, rooting out their discriminatory origins: red-lining.
"One of the things that have the clearest connection are these policies, these racist housing policies that the federal government enacted in the 1930s that we often refer to now as red-lining," said Borunda.
"They literally drew red lines around neighborhoods that were primarily inhabited by people of color and made it harder for those areas to get federally backed housing loans, and that set off this cycle of disinvestment that has really clear impacts on the shape of the neighborhoods as we see them today," she continued.
ABC7's own analysis of data from the California Health Places Index found that the cycle of disinvestment Borunda discussed still persists today.
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The HPI measures tree canopy weighted by population. In other words, it's measuring the average tree cover experienced by people near their home.
Census tracts where the median household income is less than $40,000 or $40,000 to $60,000 a year, tree canopy is about half of the tree canopy experienced by people living in census tracts where the median household income is more than $120,000 per year.
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ABC7 also found that in the city of L.A., census tracts with more trees correlate with cooler temperatures.
Those with more than 7% average tree cover experienced near their homes had surface temperatures that were at least three to four degrees cooler than census tracts with less than 7% tree cover, according to an analysis of HPI's tree cover data and temperature data from NASA's Landsat 8 satellite collected by NPR and shared via open source code.
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"There are solutions, proven solutions, data science-backed solutions," said Whitman.
"And those solutions are planting trees," she continued.
For years, Whitson and her team at Tree People have been working to engage communities to plant more trees, especially in low income communities of color in South L.A., Southeast L.A. and the San Fernando Valley. City leaders are now following their lead.
The City of Los Angeles is in the midst of planting 90,000 trees by the end of 2021.
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Burbank is also doing its part to maintain a rich tree canopy by giving residents three free trees a year and businesses 20 trees a year. They're also providing an arborist to oversee the process.
The Smith family is jumping at the offer.
"They already are starting to provide a lovely landscape to our backyard but also lower our energy bills," said Burbank resident Kristen Smith.
Burbank water and power had been sponsoring a similar program for some 10 years but the city council launched its own "plant for a greener Burbank" initiative in late 2020. The goal to plant 500 trees in 2021 already has already been surpassed.
"We're not stopping there, we're going to continue our efforts to help the greater Los Angeles area," said Grace Coronado, an administrative analyst for the City of Burbank.
National Geographic Environment Reporter Alejandra Borunda believes that more shade can help communities deal with the impacts of climate change.
"It's a piece in the puzzle that we can use to make people more resilient in the face of a problem that's only going to get harder for us to deal with in the future," she said.
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