20:17 was the third hottest year on
record and based on recent trends it's
not getting cooler anytime soon some
researchers are asking how can we stay
cool especially in our cities they're
typically hotter than rural areas but
why you can thank the urban heat island
effect on hot summer days roofs
buildings and other urban surfaces can
heat up to 90 degrees hotter than the
air
this creates islands of heat one of the
biggest contributors to those islands
dark surfaces dark surfaces absorb all
wavelengths of light and converts them
to heat so the surface gets warm it's
why your mom told you not to wear black
during a heatwave surface temperatures
can reach up to 150 degrees and since
asphalt is an insulator it traps that
heat over the course of the day then at
night when the air is cooler the heat
radiates away lighter surfaces on the
other hand absorb fewer wavelengths and
reflect the rest that way all that
energy isn't absorbed and surface
temperatures won't rise as much
so what coating our streets white help
cool down our cities enter Jeff Lazar
he's the vice president of sales for
garde top a pavement company looking to
cool off la their solution coat the
streets white we're seeing temperature
difference right now of about you know
anywhere five nine to ten degrees but
again the temperatures are pretty cool
outside right now when it's hotter
though jeff says the pavement can be up
to 30 degrees cooler with the white coat
some of the pilot programs that we've
done last year with with bureau of
streets and services la city I know they
are as well as we are taking a look at
the surfaces making sure they're holding
up making sure they're still you know
doing what we said that we're going to
do and they are in some of the some of
the neighbors are saying it you know
they do feel a little different than
this and add now and if we can lower the
temperatures by you know the the ambient
temperatures outside by a degree or two
it means a lot that may not seem like a
lot but a report by the environment
Protection Agency suggests that a
one-and-a-half degree change can make a
huge difference
Los Angeles could save over a hundred
million dollars per year and energy
savings and smog reductions but what is
the coating made of most other pavements
use coal tar some studies have been done
on that where it's it's showing that it
could have some carcinogenic effects but
guard top says that its coating is made
from recycled materials that don't have
carcinogenic additives of course LA
isn't the only warm city in the world
other US cities are also considering
coating their streets like Las Vegas but
officials they are worried that it won't
stick due to an oily road mix it uses to
combat dry climate and in New York City
volunteers have painted 7 million square
feet of rooftops white but that's only
one percent of the potential roof area
it's clear that there's still a lot of
work to be done I was never a big
climate climate guy until we started
getting into this product but when you
see what differences one degree can make
in you know in climate change it it it
makes quite a bit of difference