| Dear
EarthTalk: Is it true that the BP oil leak
is much more of an environmental threat than previous spills
from tankers, and if so why?
-- Nathan Gore, Pawtucket, RI
| |
The
National Oceanic and Atmospheric Administration recently
detected huge deepwater plumes of dispersed oil up
to 30 miles long, seven miles wide and hundreds of
feet thick. Pictured here: Workers clean off an oil-soaked
pelican at the Fort Jackson, Louisiana International
Bird Rescue Research Center.
© Lorna Baldwin, PBS NewsHour, Courtesy Flickr |
No
one knows for sure how the ongoing oil catastrophe in the
Gulf of Mexico will affect the deep sea ecosystem, but scientists
are not optimistic. Oil from what is now considered the
nation‘s second largest spill, 1989’s Exxon
Valdez mishap, slicked 11,000 square miles of ocean surface
and 1,300 miles of pristine Alaskan coastline while killing
hundreds of thousands of birds and marine mammals and untold
numbers of fish and fish eggs. But the impacts of the ongoing
Deepwater Horizon leak in the Gulf may be far worse given
that much of the loose oil is actually in the water column,
not on the surface. In fact, researchers from the National
Oceanic and Atmospheric Administration (NOAA) recently detected
huge deepwater plumes of dispersed oil up to 30 miles long,
seven miles wide and hundreds of feet thick.
Why
would an undersea spill be worse? One outcome could be the
expansion in size and extension in time of a seasonal “dead
zone” that already plagues the Gulf of Mexico as a
result of industrial pollutants and agricultural run-off
from the Mississippi River. While huge Gulf of Mexico algae
blooms help to naturally clean up the Midwest‘s factory
emissions and wasted fertilizer, such a process doesn’t
come without a cost to the ecosystem. Every spring, in a
condition known as hypoxia, this fast growing algae depletes
large sections of the Gulf‘s water column of the oxygen
crucial for other life forms to survive there. The BP oil
spill is likely to exacerbate this problem, as natural oil-eating
microbes swarming over undersea oil plumes could cause or
add to hypoxic conditions in otherwise teeming swaths of
the Gulf.
According
to NOAA researcher Samantha Joye, the undersea oil poses
a direct threat to large marine wildlife, such as fish,
sharks and cetaceans, and also to the tiny stuff, including
zooplankton, shrimp, corals, crabs and worms. By endangering
these latter populations, the foundation of the marine food
chain, the oil could have chronic long-term effects on the
wider Gulf ecosystem, including the industries—more
shrimp and oysters come from the Gulf than anywhere else
in the world—that rely on them.
Another
worry is how the chemical dispersants being used to break
up the undersea oil will impact the Gulf‘s ecosystems
and inhabitants. The dispersant‘s ingredients are
a trade secret closely held by the company that makes it,
and therefore have not been vetted by marine biologists
to determine their safety for use in such a large application.
It also remains to be seen what impact the tiny oil droplets
left in the dispersant‘s wake will have. It could
actually be worse for the undersea environment tobreak
the oil up into tiny droplets (which is done to try to make
it easier for microbes to digest them).
Beyond
all these undersea environmental effects, the oil is also
starting to wash up into coastal wetlands already besieged
by overdevelopment, pollution and the lingering effects
of Hurricane Katrina. If there can be any silver lining
to this catastrophe, it may be that it is the wake-up call
we‘ve needed to start moving more rapidly away from
fossil fuels to a clean, renewable energy future. For starters,
we can all begin to reduce our own oil consumption and opt
for clean and green energy sources whenever possible.
CONTACTS:
Deepwater
Horizon Response; NOAA.
Dear
EarthTalk: Where does ethanol as an automobile
fuel fit into the alternative energy mix? Is it better for
the environment than gasoline?
-- Donna Allgaier-Lamberti, Pullman, MI
| |
Some
eight million “flex-fuel” vehicles, which
can run on either regular gasoline or so-called E85,
a mix of 85 percent ethanol and 15 percent gasoline,
are now on U.S. roads. Unfortunately, most of them
are nowhere near an ethanol filling station, so they
are just running on conventional gasoline. Pictured:
an E85 pump in Parker, Arizona.
Chazz Layne, courtesy Flickr |
Ethanol—a
biofuel derived from corn and other feedstocks—is
already playing a major role in helping to reduce emissions
from many of the traditional gasoline-powered cars on the
road today. According to the U.S. Department of Energy,
nearly half of all the gasoline sold in the U.S. contains
up to 10 percent ethanol, which not only boosts octane but
also helps meet federally mandated air quality requirements.
By promoting more complete fuel combustion, this small amount
of ethanol mixed into gasoline reduces exhaust emissions
of carbon monoxide—a regulated pollutant linked to
smog, acid rain, global warming and other environmental
problems—by as much as 30 percent compared with pure
gasoline.
Also, a growing
number of so-called “flex-fuel” vehicles now
available can run on either straight unleaded gasoline or
so-called E85, a mix of 85 percent ethanol and 15 percent
gasoline. Ethanol proponents underscore emissions savings,
cost stability (ethanol is distilled from domestically grown
corn) and reduced reliance on (foreign) oil as benefits
of more drivers filling up their tanks with E85 instead
of gas.
But even though
some eight million flex-fuel vehicles are now on U.S. roads,
most of them are not near convenient ethanol refilling stations
and are therefore mostly running on regular gasoline. (The
U.S. Department of Energy website has a map-based listing
of E85 refueling stations across the country—most
are in the Midwest’s “corn belt.”) So
while the capacity and perhaps demand for a cleaner burning
fuel is there, supplies have not kept pace—some say
because the federal government has subsidized ethanol producers
only and not the distributors and retailers who get the
product to customers.
But this may
change. In May 2009 President Obama signed a Presidential
Directive to advance research into biofuels like ethanol
and expand their use. The resulting Biofuels Interagency
Working Group is developing a plan to increase flex fuel
vehicle use by making E85 and other biofuels more available.
While many environmental
advocates view increasing ethanol use as a promising development
(if drivers would actually fill up with it), others are
not so sure. Cornell agriculture professor David Pimentel
argues that producing ethanol actually creates a net energy
loss. His research shows that a gallon of ethanol contains
77,000 BTUs of energy for engines to burn but requires 131,000
BTUs to process into usable fuel, not including additional
BTUs burned from fossil fuel sources to power the farm equipment
to grow the corn, and the barges, trains and trucks used
to transport it to refineries and ultimately fueling stations.
Pimentel also
says that powering a car for a single year on ethanol would
require 11 acres of corn, which could alternatively feed
at least seven people. If we step up our use of ethanol
and begin putting our farmers’ yields into gas tanks
instead of on dinner tables, we could see a shortage of
domestically grown food and higher prices at the grocery
store. To address this problem, biofuels producers are researching
alternative non-food feedstocks such as algae, corn stalks,
wood chips and switchgrass, though they would still make
use of arable land that could grow food for human consumption.
CONTACTS:
U.S. Department
of Energy; Argonne
National Laboratory; E85
Fueling Station Locations. |
A
SYNDICATED COLUMN ONLY ON AMERICAJR.COM
|
