A growing body of underreported
science shows that doubling carbon
makes many plants grow faster, but
apparently not better . . .
Doubled carbon dioxide could also be bad news for timber.
Tuchman explains that trees grow faster, but their cell walls are
elongated and thinner, translating into weaker lumber.
The science can’t be completely definitive. These effects have
been shown in controlled experiments, but it could look different
— for better or worse — in a complex, planet-wide system.
Tuchman explains that trees grow
faster, but their cell walls are elon-
gated and thinner, translating into
weaker lumber.
4. MOST AMERICANS WANT TO ADDRESS THE
PROBLEM, AT LEAST SOMEWHAT
Tony Leiserowitz, who works with Decision Research in
Eugene, has some good news: Most Americans believe global
warming is a problem and think the government should tackle it.
Armed with a grant from the National Science Foundation,
Leiserowitz surveyed Americans around the country about
global warming and policies to curb it.
“I found to my surprise that there was quite strong public
support for a variety of national policies,” he says. And that
support came from all points along the political spectrum.
Three quarters of respondents said they were concerned
about global warming, 90 percent said the U.S. should take
steps to lower greenhouse-gas emissions, and 71 percent
favored shifting the roughly $5 billion of annual fossil-fuel
subsidies to support renewable energy. Eighty-eight percent
favored signing the Kyoto protocol, which calls for reduc-
ing U.S. carbon emissions 7 percent by 2010, and 76 per-
cent favored reducing those emissions even if developing
nations such as China and India don’t — the major reason
the federal government withheld its support of the Kyoto
treaty.
But Leiserowitz found the same people balked when it
came to actions that would cost them more personally. He
found that 78 percent of respondents opposed a 60-cent gas
tax to discourage driving and cut emissions. Only 31 percent
were willing to support a business-energy tax that would cost
a family of four an extra $380 per year. A small majority, 54
percent, was willing to impose a gas-guzzler tax that would
add $1,000 to the cost of a $20,000 car or SUV with gas
mileage below 25 miles per gallon.
Despite strong general support, Leiserowitz concludes,
“People are a long way from being convinced that they need
to personally sacrifice to achieve those goals. I don’t think
people have a good sense yet of the scale of the problem, or
the kinds of commitments that will be required to solve it at
the societal level.”
His latest NSF grant is to study the effects of The Day
After Tomorrow on public perceptions of climate change.
3. MORE ATMOSPHERIC WARMING MAY HARM
TIMBER, AGRICULTURE AND ECOSYSTEMS
There’s little debate that carbon levels are expected to dou-
ble from pre-industrial levels by 2050. Many people see that
fact as the silver lining of global-warming scenarios because
extra carbon is thought to boost food production — commer-
cial greenhouses routinely pump in extra carbon dioxide to
make plants more lush for sale.
But a growing body of underreported science shows that
doubling carbon makes many plants grow faster, but appar-
ently not better.
Nancy Tuchman, a professor of stream ecology at Loyola
University of Chicago, has been studying the effects of doubled
carbon levels on the food quality of deciduous tree leaves. Those
leaves fall into streams, forming the base of the food chain there.
What she’s found is that the trees grow faster with more
carbon dioxide, but their nutritional value to the food chain
plummets.
The trees gorge on carbon, but they are limited by lower
levels of nitrogen in the soil. The extra carbon lets the plants
make more phenolics — undigestible compounds that serve as
a defense mechanism against leaf eaters. Also, less nitrogen
means less grist for making protein, so anything that relies on
these leaves for food has to eat more to gain less. Tuchman has
documented this diminished nutrition up the stream food
chain — from microorganisms and fungi to insects and fish.
This effect has been shown to include many of the foods
humans eat, including mainstays such as broccoli and Brussels
sprouts, carrots and potatoes, tomatoes and apples. (Wheat,
barley and many staple grains appear unaffected.) If carbon
levels keep rising, diminished nutrition will likely show up in
plant-eating animals as well, including those many animals
that humans depend on for food.
5. OREGON IS A LEADER IN BATTLING GLOBAL
WARMING
There’s more good news: Oregon is taking important and
ground-breaking strides to lower its contribution to climate
change.
In 1997, the Oregon Legislature unanimously required
new power plants to reduce carbon emissions 17 percent
below the best available technology — or help fund measures
to reduce carbon in other ways. The law was the first of its
kind in the U.S.; Washington state recently followed with its
own version. New power plants basically multiply their extra
carbon by a dollar figure set by law. All to date have given that
money to Climate Trust, a Portland-based nonprofit, which in
turn funds carbon-cutting projects on the ground.
Mike Burnett, Climate Trust’s executive director, says his
group has put $5 million into about 10 projects so far, includ-
ing stimulating wind power in Oregon and planting trees along
the Deschutes River. Many other projects are in the Portland
metro area, including low-income weatherization, timing traf-
fic signals to reduce idling at red lights and new green build-
ings. “Some of the most efficient buildings in the world are
being built in Portland under our program,” Burnett says.
These efforts don’t entirely do the job. In fact, Climate
Trust is only offsetting about one third of the carbon it’s paid
to offset, Burnett says, because these projects cost more than
the law requires power producers to pay.
Oregon also is participating in regional efforts, and in
September 2003 joined forces with the other West Coast states
to take combined action. The agreement among the three gov-
ernors is the second of its kind in the nation, following a 2001
action by governors in the Northeast and some eastern
Canadian provincial leaders to tackle climate change after
President George W. Bush backed away from his campaign
promise to regulate carbon.
Under the agreement, the three West Coast states could
begin to implement cap-and-trade schemes for carbon —
companies emitting too much carbon could buy credits from
companies emitting less. The states also could work together
to encourage development of renewable energy, and combine
vehicle purchases to green state fleets with hybrid cars and
tires that help vehicles use less fuel.
Cities are taking their own initiatives. Portland, Corvallis
and a number of Washington municipalities have joined Cities
for Climate Protection, committing to cleaning up their carbon
act. Eugene didn’t join when the opportunity came around
four years ago, but Councilman David Kelly says the city is
nevertheless doing what it can.
“If you want to start poking holes at this film with the science, you’re going to end up with Swiss cheese,”
says Tony Leiserowitz, a Eugene researcher who has focused on the issue of human-caused climate disruption
for more than a decade. But, he adds, “You’ll still have cheese; there’s still something there, even if there’s a lot
of holes in it.”
© TWENTIETH CENTURY FOX
In this still from the film The Day After Tomorrow, a tsunami floods New York City in the wake of a catastrophic climatic shift.
JUNE 10, 2004 13