In the northern United States, weatherizing programs have
historically focused on the colder months of the year, and the word
itself likely conjures thoughts of long and frigid winters.
But warming temperatures from climate change mean the concept
increasingly pertains to the other end of the calendar too: the summer
months, which are getting hotter and putting more people at risk of
potentially deadly heat-related illnesses.
With even New England cities like Boston expected to see as many as
42 days a year when temperatures crest 90 degrees Fahrenheit by 2050, it
and others around the world are developing new approaches and adapting
old ones to help people cope.
The need is great.
Extreme heat kills more people each year than any other type of
weather-related event. Last year when the Biden administration launched a
federal plan to address the problem, White House climate advisor Gina
McCarthy called extreme heat a “silent killer.”
Statistics show that annual heat-related deaths in the United States
surpass mortalities from tornadoes, hurricanes, flooding, and cold
winter weather combined, though the problem gets much less attention.
Those risks can be amplified in “heat islands” — urban areas where
temperatures can be 10 or 20 degrees Fahrenheit hotter than in other
parts of the same city. Disasters of our own design, they occur in
places with few shade-supplying trees and a lot of buildings and
pavement.
Climate change is making heat islands worse. And it’s a problem that extends well beyond Boston and the Northeast.
“Urban heat islands are a phenomenon that we’re seeing occurring
pretty much in every city across the globe,” says to Yusuf Jameel,
research manager at Project Drawdown, an international organization
working on solutions to climate change.
The danger
Heat waves — and the concentrated effects of heat islands — pose
grave health risks like dehydration, mental stress and even death. Last
summer about 800 people died in Oregon, Washington and British Columbia
when a heatwave hit the Pacific Northwest.
Experts say the true death rate associated with heat emergencies may in fact be even higher than reported,
since exposure to heat extremes can precipitate medical emergencies in
people with conditions including diabetes and heart, respiratory and
kidney ailments. These health events aren’t always included in official
statistics of heat-induced emergencies.
The very young and very old, pregnant women, and people who spend a
lot of time in the heat — such as people who work outdoors, the
unhoused, and people who can’t afford to cool their homes — also face
higher risks than people who spend all their time in air-conditioned
homes, offices and cars whenever temperatures spike.
“We have to take little breaks to get out of the sun,” says a
building custodian in D.C.’s Columbia Heights neighborhood — one of the
hottest places in the city — who asked to remain anonymous. “I get
dizzy,” she adds. “Sometimes I feel like I’m going to vomit,” due to
exposure to too much heat.
Some medications can also increase heat sensitivity,
and extreme heat can amplify drug side effects. Exposure to heat can
also diminish cognitive function, even in healthy young adults, according to researchers, which could cause life-long consequences by limiting academic and professional achievement and earnings potential.
It’s also an environmental justice issue.
A growing body of research
shows worldwide urban heat islands are predominantly located in
low-income neighborhoods. In the United States, those neighborhoods are
overwhelmingly home to people of color and immigrants.
Compounding matters, these same low-income areas tend to have higher
percentages of people with medical conditions that make them
particularly susceptible to heat-related illness.
Research has also linked heat islands to the country’s history of
discriminatory lending practices and a past federal housing policy known
as “redlining,” which led to much less public and private investment
and access to home loans in many communities of color over the last
century.
While redlining was outlawed in 1968, the past policies, experts say,
continue have negative consequences in these communities today. In the
past few years, scientists have published multiple studies
documenting the heat islands that exist today in formerly redlined
areas of more than 100 U.S. cities, even while adjacent neighborhoods
remain much cooler.
A global issue
It’s not just communities in the United States that are feeling the heat — or the inequity.
Poorer countries, says Jameel, have huge challenges for people living in heat islands, particularly those who work outdoors.
“The stakes are very, very high,” he says. For example, heat waves in India and Pakistan earlier this year saw temperatures as high as 122 degrees Fahrenheit
and claimed at least 90 lives. “People were unable to work. There was a
higher incidence of people being hospitalized. Kids were unable to go
to school.”
He also notes that children going to school in consistently hot
indoor spaces can end up with both health problems and long-term
economic impacts if the heat impairs their ability to learn and
function.
As heatwaves become more severe and more frequent with climate warming, the economic toll can be high, as well.
“Right now, it’s happening maybe two weeks a year, where the
temperatures are so high that people are unable to work outside,” he
says. “But in five to 10 years, if it becomes a month [per year], that
will affect the economic growth of the country.”
Those days, however, may already be here. In Delhi, the heatwave this
spring resulted in nearly 100 days with temperatures breaking 100
degrees Fahrenheit.
That’s why climate change — and the associated heat risks — are
“fundamentally an issue of justice and equality,” he says. “Children
born in sub-Saharan African countries in 2020 are projected to
experience six times more extreme climate events compared to those born
in the 1960s.”
The countries that will be hardest hit by climate change are also among those that have contributed least to the problem.
Finding solutions
Work has begun in some places to tackle the heat.
Ahmedabad, India has been leading this work in South Asia, with the first Heat Action Plan
established in 2013. It includes a citywide Cool Roof program that uses
light-colored roofing materials or paints to reflect the sun’s rays
rather than absorb them.
Retrofitting solutions are good. But longer term, Jameel says, cities need to prioritize green space, not just more buildings.
Such urban-planning solutions are challenging in developing
countries, he says, where new urban neighborhoods often spring up
spontaneously, without formal planning.
Nevertheless, the Global South has one advantage over the North: long
experience with the heat. One place to look for solutions, Jameel says,
is local knowledge passed down for generations. For example,
traditional building designs strategically placed windows to allow
indoor heat to escape outdoors and encourage cross ventilation.
But while these types of traditional building designs may continue to
get built one at a time, Jameel said such projects are not being built
“at scale” by real estate developers, who could have a greater impact.
He and other experts say much more needs to be done to raise general
awareness about heat and health, help vulnerable residents, and spark
building-code changes to address the leading cause of weather-related
deaths.
The U.S. response
In the United States, the federal government and some cities have begun to act, too.
In Boston’s Heat Resilience Solutions Plan,
90% of respondents to the city’s online survey said it’s too hot in
their homes during very hot summer days. The plan, published in April
after more than a year of citywide public consultations, also found that
42% of Black and 36% of Latino residents reported that it was “always”
too hot at home, compared to 24% of white residents.
In response to these risks, government authorities are adapting
programs originally created to help low-income residents keep the heat
on during the winter months.
The Mayor’s Office on Housing is considering providing
“income-qualified residents” not just with air-conditioning units, but
with summer utility bill subsidies, too — similar to what’s already
available to help heat homes in the winter. That proposal is an
acknowledgment that paying the higher monthly bills for running those
ACs has become a bigger barrier to household cooling than just acquiring
an air conditioner.
Boston is not alone. After deadly heat waves last year in the Pacific Northwest, Oregon passed new legislation that will direct $5 million toward purchasing air-conditioning units for vulnerable residents.
At the national level, the Department of Health and Human Services this spring announced plans to send states an infusion of $385 million
in new funds from the Low Income Home Energy Assistance Program. A
portion of the funds were to cover utility payments, “including summer
cooling” for households that need help catching up on unpaid bills.
City, state and federal governments
are also starting to roll out new weatherizing assistance and
interest-free home-improvement loan programs to help residents pay for
adding or upgrading air conditioning.
A comprehensive approach
More air conditioning, however, is hardly a long-term solution, since
the exhaust from indoor climate control heats up the air outside and
the electricity needed to run them fuels more climate change. Experts
say we need to redesign our homes, offices and entire cities, a costly
undertaking that is still in its incipient stages even in the
resource-rich Global North.
Some of that work is underway.
Many U.S. cities, such as New York, Chicago, Portland and Los
Angeles, are adding “cool roof” or “green roof” programs to bring down
indoor temperatures and decrease air-conditioning costs by using
reflective roofing materials or planting vegetation on roofs.
Some cities are going even further. In 2018 Washington, D.C., passed
tougher new standards to increase building energy performance in an
effort to reduce greenhouse gas emissions and energy consumption by 50%
by 2032.
Meanwhile Boston is spending $20 million on a retrofit pilot that
focuses on providing owners of multifamily buildings with affordable
help to upgrade their cooling and heating systems. The program is
expected to fund “deep energy retrofits” designed to improve efficiency
for about 300 “housing units” in public housing buildings or those
otherwise deemed “affordable” by the city.
The city’s heat plan also calls for the formation of a task force to
address the immediate problem, as well as developing “the broader heat
relief strategy,” with long-term solutions.
Working with nonprofit partners, it’s providing households and small
businesses in the city’s low-income areas with help paying for equipment
upgrades and retrofits. The plan details 26 strategies it plans to
implement, working through community organizations and directly with
city residents. The strategies include grant programs to help building
owners afford energy efficient heat pumps and cool roofs, as well as
planting trees and adding awnings to provide shade at bus stops.
Assisted by new data analysis and mapping technology, many cities are
homing in on urban heat islands to better understand the history and
historic discrimination that has led to dramatically higher temperatures
from neighborhood to neighborhood — and to tailor solutions to local
realities.
King County Metro Transit, in the Seattle area, is using heat-mapping data
to guide bus stop design and amenities with consideration to extreme
weather — especially in communities most acutely affected by climate
change.
And Chelsea, Massachusetts, has launched a “Cool Block”
project that involves planting trees, repaving dark asphalt streets in
lighter gray material, and revamping sidewalks with white concrete,
porous pavers and planters.
It’s possible to address climate-related health threats and historic
wrongs at the same time, says Jeremy Hoffman, the David and Jane Cohn
scientist at the Science Museum of Virginia,
who has lead heat islands studies in several U.S. cities and worked on
research studies linking redlining and historic discrimination with the
locations of today’s heat islands in cities across the country.
“These decisions that were made a century ago by a few people have
affected a ton of people in the present day,” he says. “Collectively we
still have a long way to go, but if communities and local governments
work together, we can make decisions that will have positive impact for
the next century or beyond.”