"You OK in here?"
We all know what it feels
like to be too hot.
"Why is it so hot in here?"
"(Sigh) Man, is it hot!"
And it's not your imagination. [Washington Post headline: Summer in America is becoming hotter, longer and more dangerous]
Summers in the U.S. are getting hotter. [Washington Post headline: Summer in America is becoming hotter, longer and more dangerous]
Since the 1960s, heat waves
have become more and more frequent.
And when they happen, they last longer.
Compared to hurricanes, floods
and tornadoes, heat is invisible.
Yet in the U.S., it's the number one
weather-related cause of death.
So heat is a big problem.
But there are things we can do right now
to protect ourselves from extreme heat.
"In California, there are cities
where a third of the year,
it's going to be over 100 degrees outside
and that's going to be sort of
the new normal."
This is V. Kelly Turner.
She's co-director of UCLA's Luskin Center
for Innovation and she
studies urban heat.
Trees and plants
naturally cool the air,
but cities are covered
with materials like asphalt
that absorb heat during the day
and then slowly radiate it back out.
Wide streets, parking lots —
all of it heats up the air.
And then human activity like car
emissions also creates heat.
Take a look at this map
created by researchers at
UC San Diego.
It tracks surface temperature
and if you look at the cities,
you see these big spikes in temperature.
We haven't done ourselves
any favors in the way we plan
and build cities.
It's causing cities
to be hotter and it's a problem
that's particularly acute in
low-income and communities of color
because of ways
we've invested
in those communities and built them.
A study out of UC Davis
found that on extreme heat days,
California's poorest
neighborhoods were on average
five degrees hotter
than the wealthiest ones.
Look at this surface temperature
map of L.A.
and then look at this
map of tree coverage.
The areas with fewer trees
have the hottest daytime temperatures.
In a paper called "Trees Grown On Money,"
researchers found that
the amount of trees in a neighborhood
strongly correlates with median
household income.
This is especially true in arid cities
like L.A.
Trees need water
and care to survive —
and that means investment.
"And the most important thing
we can do to cool people
when they're outside
is to provide more shade.
My close colleague
and collaborator, Ariane Middel,
just published a paper called
'50 Grades of Shade.'
She comes up with the best titles."
Ariane found that on a
hot and sunny day,
shade can reduce the heat load
on your body by 50 degrees.
That makes a huge difference.
My team looked at municipal plans
from the 50 largest cities in the U.S.
and we found that the overwhelming
majority don't even include shade
in any of their heat planning documents
and if they do, they only include trees.
Trees are great,
but they don't work in every situation.
Things like bus shelters
and sunshades
are all great ways
to quickly address shade deserts.
Think about a playground
in the sun on a hot day.
This slide has a surface temperature
around 120 degrees Fahrenheit.
Something like a sunshade
could make it safe to use.
Cities are beginning
to test out solutions.
The Cool Streets Initiative in L.A.
focuses on the most
vulnerable neighborhoods in the
city by planting trees
and adding cool pavement,
which is this special material
that stays cooler than
traditional asphalt.
But we'll also have to
think beyond outdoor interventions.
"During extreme heat,
people need to get
their core temperatures down,
and they can't get it down
low enough
unless they're inside a cool shelter."
Nearly a quarter of California households
don't have air conditioning.
And while it's illegal for a landlord
to rent an apartment
without heat in the winter,
it's perfectly legal
to rent a unit that's too hot to live in.
But a growing number of cities
are starting to take urban heat seriously.
L.A. has just established
a chief heat officer,
so the issue doesn't fall
through the cracks
like it has in the past.
And once you begin thinking about
what it will be like
to live in a world where it's regularly
over a hundred degrees,
it's easy to see how this issue
connects to so many others —
like vulnerabilities in our energy grid.
"State officials
warning rolling blackouts
may be in our future"
People's working conditions.
"We're learning more about that
alarming video of a UPS guy in
distress, overwhelmed by the 110 degree
temperature in Arizona"
And our food system.
"This puts a little strain both on
our people and our crops."
Good urban planning
and protection from heat
can no longer be treated as luxury items.
For our cities to function in the heat,
we all need cooler
homes and streets and schools.
If you want to learn more about
cooling down during a heat wave,
check out our story
at universityofcalifornia.edu/fig1.
We've also got links to the studies
we mentioned in the video description.
If you found this video
useful, give us a like.
It will help other people find us.
And let us know in the comments
if there are other topics
you want us to cover in the future.