Street roots., September 02, 2016, Page 7, Image 7

Street Roots • Sept. 2-8, 2016
News
Page 7
With few shade trees and a lot of pavement, urban heat islands are
hotter than the average neighborhood, posing health risks for residents
BY AMANDA WALDROUPE
STAFF WRITER
ortland, unlike the rest of the nation,
has had a relatively cool summer this
year.
Even so, 2016 has so far been the hottest
year on record, according to the National
Oceanic and Atmospheric Administration. The
past three years rank among the five hottest
years since 1880,
"Urban heat islands completely when data collection
started.
overlap in many ways with
As climate change
those communities that have
quickens and its
the least resources."
effects increase,
VIVEK SHANDAS, Portland is expected
PSU PROFESSOR WHO
to have longer, drier
DEVELOPED A MAP CHARTING
PORTLAND'S URBAN HEAT ISLANDS
summers, more days
that are hotter on
average and more
heat waves that last longer.
During heat waves, like the one Portland
experienced in late August, nowhere is the
effect of hot days more pronounced than in
Portland’s urban heat islands.
Heat islands are places in a city as small as
a city block or as big as an entire
neighborhood that are hotter than average
recorded temperatures. The increased heat is
the result of few trees and other greenery to
provide canopy and shade, coupled with large
swaths of pavement, parking lots, black
rooftops and other materials that absorb and
P
slowly release heat
Heat islands are neighborhoodwide
broilers. During the recent mid-August heat
wave, according to the Weather
Underground, the temperature in the
Irvington neighborhood, on Northeast
Klickitat Street between 22nd and 23rd
avenues, was 100 degrees. The temperature
in the Lents neighborhood, east of Interstate
205 and between Southeast Holgate and
Powell boulevards, was nearly 105.
As climate change continues, the effect of
urban heat islands will only become more
pronounced — and more harmful to the health
of people living in those neighborhoods. The
city of Portland, Multnomah County and a
variety of nonprofits are beginning to take
steps to reduce the effect of urban heat
islands, both to improve environmental health
and to create equity throughout Portland.
“It is an increasingly big problem for us to
confront,” said Vivek Shandas, a professor in
Portland State University’s School of Urban
Studies who developed a map charting
Portland’s urban heat islands. “Heat waves kill
more people in the U.S. than all other natural
disasters. It is a silent killer. That’s the
concern. (We need to identify) what can we do
to help transition our neighborhoods and our
entire city to be climate resilient”
“With climate change, we really have a
timeline,” said John Wasiutynski, director of
Multnomah County’s Office of Sustainability.
“As the climate warms and we have these
hotter summers and more extreme weather,
it’s going to (be) hardest on the people who
are furthest on the margins. We have to get to
this right now.”
n 2015, Shandas, a group of researchers and
PSU graduate students, began mounting
small thermometers onto their cars and bikes.
The thermometers were connected to a global
positioning system, and as the researchers
drove throughout the city, the thermometers
recorded the temperature, down to the tenth
of a degree, each second.
Shandas mapped the composite data,
creating a map identifying the coolest and
hottest places in Portland. The hottest parts of
the city — Portland’s urban heat islands -
include areas along the Interstate 5, 84 and
205 corridors, parts of north and northeast
Portland, the central eastside industrial area,
parts of downtown, and almost all of Portland
east of 1-205.
Those parts of the city, Shandas and others
said, have more asphalt and parking lots,
which absorb and trap heat During heat
waves, those materials do not release the heat
quickly enough, which means that over a
period of days, the area can get — and feel —
hotter and hotter.
“That heat will actually get massed,
accumulate in those hard surfaces and radiate
I
See HEAT, page 12