The news this week about global climate change is NOT good. . .Anyone who is interested in environmental science knows that the clock has been ticking for quite a while on how long humans can go on destroying the planet before it becomes unlivable. . .Well, we are now at a point of a major crisis.

So what do we do? Wring our hands and exclaim, “The sky is falling!” OR change our habits?

For those of us who are walkers, using our cars less and our feet more is one way to do this. But when it is too hot or smoky to be able to walk, what then? Well, then we need to start advocating for change. . .and one idea that could really help our whole world is creating more cooling corridors.

What are Cooling Corridors?

Interestingly, they are a return to an age-old ideal . . . the tree-lined path, long held as the quintessential walking path.

And why are they important? Because under tree cover, temperatures drop up to fifteen degrees. Not to mention, trees create much-needed oxygen in polluted urban envirnoments.

Throughout this summer’s heatwaves, urban areas have particularly suffered — and the parts of urban areas that suffer most are the lower-income areas, where there is almost always less tree cover. A recent article in the Seattle Times points out the striking disparity between aerial photographs of wealthier North Seattle vs the South Side.

“If you look at aerial photographs, north Seattle looks like a forest,” said Washington state Rep. Bill Ramos, a suburban Democrat who sponsored a bill the legislature recently passed to help cities improve their tree canopy.

“On the south side, you see nothing but rooftops and asphalt and not a green thing anywhere. It’s strictly a matter of socioeconomics and race.”

The article goes on to reveal: “That disparity is not unique to Seattle. American Forests, a Washington, D.C.-based conservation nonprofit group, released a nationwide analysis last month showing that low-income neighborhoods and communities of color have significantly less tree canopy. Those areas also are more likely to suffer from the urban heat island effect caused by a lack of shade and an abundance of heat-absorbing asphalt. Heat islands can be as much as 10 degrees hotter than surrounding neighborhoods.

“We found that the wealthiest neighborhoods have 65 percent more tree canopy cover than the highest poverty neighborhoods,” said Ian Leahy, the group’s vice president of urban forestry. “As cities are beginning to heat up due to climate change, people are realizing that trees are critical infrastructure. I’ve never seen as much momentum toward urban forestry across the board.”

Now, throughout the country, there is an urgent attempt to change this. . .first by acknowledging how racist policies have almost always accompanied inequities in the urban tree canopy.

Trees are nature’s air conditioners and air purifiers. We need trees more than ever. This means not only do we need to plant more trees, but we need to prioritize their maintenance and the protection of existing trees.

Race and socioeconomic status are directly correlated to heat-related illnesses and fatalities.“The data shows that Latinos and African Americans have a higher likelihood of dying after five days of extreme heat, and that’s an injustice,” said Cindy Montañez, chief executive of Tree People, a nonprofit organization that works on planting and education projects near Los Angeles. “Planting trees is not about carbon reduction, it’s about saving lives.

“Nineteen percent of all the tree canopy cover in Los Angeles exists where 1 percent of our population lives, concentrated in these affluent areas,” Malarich said. “The conversation has changed, and there are more public officials recognizing that tree canopy is not a beautification measure, but a central piece of our infrastructure.”

Not to mention, trees also filter air pollution and storm-water runoff, as well as increase mental health and cognitive function. That’s why cities such as Phoenix are partnering with American Forests to create equitable tree canopy across all its neighborhoods as well as to create cooling corridors and pathways.

This won’t be easy — which is where we walkers come in. We can take action within our communities to advocate for more tree equity as well as to help maintain the growth of these trees. Trees can’t just be planted. They must be maintained. We, as walkers, often notice trees that haven’t been pruned or maintained. They’re the ones whose branches fall in our paths or under which we have to duck. This alone should inspire us to be a voice for tree maintenance in our communities — as well as for tree ordinances that will give these new tree initiatives the best chance to survive and flourish.

Kesha Braunskill, urban forestry coordinator with the Delaware Forest Service, said tree equity programs need to have a stronger workforce and a consistent presence in the areas they’re trying to reach.

“We need more of us, and more of us that look like the communities we serve,” she said. “We have to formulate relationships. We can’t just walk in, plant a tree and walk away.”

The Science of Cooling Corridors

In a recent study by Dr Umberto Berardi of Ryerson University in Canada, key components to creating cooling corridors were identified:

  • Reduced energy use: Trees and vegetation that directly shade buildings decrease demand for air conditioning.
  • Improved air quality and lower greenhouse gas emissions: By reducing energy demand, trees and vegetation decrease the production of associated air pollution and greenhouse gas emissions. They also remove air pollutants and store and sequester carbon dioxide.
  • Enhanced stormwater management and water quality: Vegetation reduces runoff and improves water quality by absorbing and filtering rainwater.
  • Reduced pavement maintenance: Tree shade can slow deterioration of street pavement, decreasing the amount of maintenance needed.
  • Improved quality of life: Trees and vegetation provide aesthetic value, habitat for many species, and can reduce noise.

This has been proven to great effect in Colombia’s second-largest city, Medellin, which has implemented the ‘Green Corridors’ project, transforming 18 roads and 12 waterways into lush, green havens of cool shade. These Green Corridors have helped to reduce the urban “heat island” effect—when pollution and high population density turn cities into urban heat islands, with significantly higher temperatures than the surrounding rural areas. The introduction of 8,300 trees and 350,000 shrubs has reduced the surface temperature in Medellin by up to seven degrees and has also improved air quality and biodiversity. Not to mention creating a more beautiful city where cyclist and pedestrians are encouraged to leave their cars behind.

Similarly, after the 2003 heatwave in Paris, France, which resulted in tens of thousands of deaths, Paris installed over 900 “cool islands” while Mexico City has created the Via Verde Project, turning over 1,000 highway pillars into vertical gardens.

As we all become increasingly affected by climate change, it is up to each of us to do our part to help future generations of humans, animals, birds and marine life survive!

As walkers, why not become more involved in helping our communities create cooling corridors and reducing heat islands? Let’s advocate for tree equity and education and do our part to combat climate change as we walk!