Page 28 - ARUBA TODAY

A28 SCIENCE
Wednesday 2 May 2018

America's air isn't getting cleaner as fast as it used to

By SETH BORENSTEIN, AP but that has been delayed
DENVER (AP) — For de- once already. More than
cades America's air was 170 counties in the United
getting cleaner as levels States are already exceed-
of a key smog ingredient ing the older clean air stan-
steadily dropped. That dard for smog, according
changed about seven to the EPA. Worden and
years ago when pollution colleagues tried to figure
reductions leveled off, a out what was happening,
new study found. ruling out the flow of the
This means when tighter smog ingredient from Chi-
federal air quality stan- na since levels in that coun-
dards go into effect later try went down since it tight-
this year, many more cities ened its air quality rules.
may find themselves on the While the 2008 recession
dirty air list. There are sev- may have played a role
eral reasons for the flatten- in the slowdown, Worden
ing of nitrogen oxide levels said there were other big-
including hard-to-reduce ger factors at play. The big-
industrial and truck pollu- In this March 19, 2015, file photo, a thick haze of smog looms over the skyline of Chicago. gest and easiest pollution
tion, said study co-author Associated Press reductions have already
Helen Worden, a scientist been achieved, leaving
at the National Center for gredient in smog. Levels models overestimate how come from cars, trucks, smaller, more difficult cuts,
Atmospheric Research in fell 7 percent from 2005 to clean the air really is, said power and industrial plants. Worden said. University of
Boulder, Colorado. 2009, but only dropped 1.7 University of North Caro- In 2015, the EPA proposed Maryland air scientist Ross
The study, in Monday's Pro- percent from 2011 to 2015. lina's Jason West, who new air quality standards Salawitch said exposure to
ceedings of the National "We can't say anymore it's wasn't part of the study. limiting smog levels to 70 elevated ozone can lead
Academy of Sciences, going down," Worden said. Smog is created when ni- parts per billion, down from to coughing and difficulty
used satellite and ground The results also show the trogen oxides and volatile the current 75 parts per bil- breathing, and make re-
measurements to track ni- U.S. Environmental Protec- organic compounds cook lion. Those rules are slated spiratory diseases such as
trogen oxides, a major in- tion Agency's computer in sunlight. Those chemicals to go into effect this fall, asthma worse.q

Scientists hope bug experiment

fattens Colorado River fish

Researchers with the U.S. in black flies and midges die, said Jeff Muehlbauer,
Geological Survey are by next summer, and the a research ecologist with
hoping a months long ex- eventual return of bigger the Geological Survey.
periment to release low, bugs seen in other stretches The so-called bug flows are
steady flows of water from of the Colorado River that part of a larger plan ap-
Glen Canyon Dam will give largely have disappeared proved in late 2016 to man-
the eggs that bugs lay just from a prized fishery known age operations at Glen
below the water's surface a as Lees Ferry. When insects Canyon Dam, which holds
better chance at survival. It thrive, so do fish, bats, birds back Lake Powell. The plan
This undated photo shows an adult midge, about ¼ inch (6 mil-
limeters) long, the most common type of aquatic insect found in starts this weekend. and other predators, scien- allows for high flows to push
the Colorado River ecosystem. "For whatever reason, tists say. sand built up in Colorado
Associated Press downstream of Glen Can- Insects attach their eggs River tributaries through the
yon Dam really lacks diver- to hard surfaces like rocks, Grand Canyon as well as
By FELICIA FONSECA anglers have been pulling sity," said Scott VanderKooi, wood or cattails near the other experiments with the
FLAGSTAFF, Ariz. (AP) — out long, skinny trout that who oversees the U.S. river's shore. Fluctuations in flow that could help non-
Any great fishing hole de- don't give up much of a Geological Survey's Grand the water for hydropower native trout.
pends on the health and fight with a hook in their Canyon Monitoring and create artificial tides that "It's an ongoing endeavor
well-being of its bugs. mouths. Research Center in Flag- can expose the eggs and to understand first, what's
In a key stretch of the Colo- Turns out, they don't have staff. dry them out. the status of all these dif-
rado River below a dam on enough to eat, scientists Scientists are anticipat- If they're not back under- ferent resources — the
the Arizona-Utah border, say. ing a 26 percent increase water within an hour, they fish, the sandbars, the cul-
tural resources — and then
making adjustments based
on how the ecosystem is
changing," John Hamill
said, a volunteer with Trout
Unlimited who helped work
on the plan.
The flows won't change
the amount of water the
U.S. Bureau of Reclamation
must deliver to three states
and Mexico.q