we have discovered here is
that the ocean has been doing its job for the past century in collecting most
of the surplus CO2 we have been producing.
It is very useful information.
We already know that excess CO2
in the atmosphere is largely a lagging response to a global warming trend
caused by the recovery from the little ice age.
I would go so far as to exclude it as a factor just to make the point
that any conclusions drawn from that can not be trusted.
The one CO2 sink available
happens to be the ocean and it can and will collect surplus CO2. Suddenly we have real confirmation that that
is exactly what is happening. It is also
not over and we will have a great deal of this extra CO2 to deal with for
another century at least. Recall that we
are about to completely exit the carbon economy over the next two decades as a
direct result of in place breakthroughs.
My guess and it is only a guess
is that almost all the CO2 produced by the burning of geological carbon ended
up in the Ocean.
The great oyster crash
written by Eric
Scigliano.
In the summer of 2007, something strange and troubling happened at the
Whiskey Creek Shellfish Hatchery on Netarts
Bay in Oregon ,
which raises oyster larvae for shellfish growers from Mexico to Canada . The hatchery's
"seed," as the oyster larvae are called, began dying by the millions,
for no apparent reason.
Disease isn't uncommon in a hatchery's tanks, but that same year, up
the coast in Washington , wild oyster larvae
also failed in Willapa Bay , which has been the heart of the Pacific Northwest 's oyster industry since the 1850s.
The Willapa
Bay growers scrambled to
replace their natural beds with farm-raised seed from Whiskey Creek and other
hatcheries. But there was very little of it to buy. Washington state's Taylor Shellfish
Farms, the Pacific Coast's largest grower, also lost most of its larvae
that year.
The situation was dire. Whiskey Creek and Taylor are key links in the nation's seafood
supply chain. They and another Washington hatchery provide nearly all the seed
for the West Coast's growers, who in turn produce more than a quarter of the
700 million or so farmed oysters that Americans slurp down every year.
Suddenly, it seemed, seafood lovers might have to do without their
slippery delicacies, or at least pay a lot more for them. Growers on the Gulf
and Atlantic coasts wondered if whatever was
striking the Pacific hatcheries might soon hit them. And when the culprit was
finally revealed, it provided the first example of how a worldwide crisis in
ocean chemistry could devastate coastal economies and change restaurant menus
across the country.
Whiskey Creek is owned by the husband-and-wife team of Sue Cudd and
Mark Wiegardt. Wiegardt grew up tending oysters on Willapa Bay, where his
family has been farming them since the late 1800s. Cudd, a fisheries biologist,
got a job at the Wiegardt operation in 1984 and married Mark in 1989. She began
managing the 33-year-old Whiskey Creek Hatchery in the mid-90s, and the couple took
over the business together in 2002.
At the sprawling, barn-like warren about two hours west of Portland , where
cylindrical plastic tanks serve as incubators for shellfish larvae and algae, a
big part of their job is to keep vigilant watch for infections. When the 2007
crisis hit, Cudd and Wiegardt set about solving it according to standard
industry practice: by looking for whatever pathogen might be making their
"babies" sick.
They eventually found a larvae-eating bacterium called Vibrio tubiashii raging through their tanks. Attacking
it with maximum force, they hired an engineer-turned-hatchery manager from Oregon State
University named Alan
Barton to build a $200,000 state-of-the-art system to filter and sterilize the
water they drew from the bay. It squelched the Vibrio but failed to
stop the carnage; the infestation, it seemed, was a symptom of some underlying
problem, rather than the cause. The larvae were still dying, and Cudd and
Wiegardt were facing ruin. So were many of the Pacific oyster farmers who
relied on them.
Wiegardt has a farmer's weatherbeaten face and stoic manner. Like all
farmers, he's used to boom-and-bust cycles. But even he started to despair.
"The frustrating thing is people in the industry saying, 'It's got to be
something you're doing wrong.'" His colleagues and competitors stopped
their scoffing as news of other die-offs began to trickle in. In 2008, in an
unprecedented cooperative effort for the industry, the Pacific Coast Shellfish Growers
Association declared a "seed supply crisis." It persuaded
its members to donate $40,000 so that Wiegardt and Cudd could keep Barton on
the payroll and on the hunt for the culprit, in hopes of helping eradicate it
elsewhere.
"We'd done everything we could to eliminate bacteria," Barton
says in his native Georgia
drawl. He began to wonder if something more fundamental might be amiss --
something in the makeup of the sea itself. "Shellfish hatcheries never
worried about chemistry, just infections. I was back to being a 14-year-old kid
with an aquarium, worrying about water chemistry."
Uncovering a killer
In July 2008, all of the remaining larvae at Whiskey Creek died
suddenly. At the same time, the water in Netarts Bay
(and hence in the hatchery's tanks) became noticeably more acidic -- an
indication that it had welled up from lower depths offshore.
This wasn't entirely unexpected: Each summer, the north wind periodically
pushes back the water along the Oregon
coast, allowing deep, cold offshore water to surge in toward land. Barton
checked federal
CoastWatch reports and confirmed that a strong upwelling had been
underway at the time the larvae died.
It was the breakthrough Whiskey Creek's operators had been waiting for.
The culprit behind their die-offs, it turned out, was part of a much bigger
change in oceans around the world. Called "ocean acidification,"
it results from too much carbon dioxide in the atmosphere. The sea is the
world's great carbon sink, holding about 50 times as much of the element as the
air. Phytoplankton at the ocean's surface absorb carbon dioxide for
photosynthesis, and when the tiny plants die, they sink and decompose,
releasing CO2 into the water column. Dissolved CO2 forms carbonic acid, the
same weak acid that gives soda water its tang. Cold water can hold more CO2, so
the frigid waters at the ocean bottom are more carbon-saturated, and more
acidic, than the warmer surface water above.
Some people think that's a good thing; scientists and engineers have
even proposed pumping CO2 into the deep ocean for storage, as a possible
strategy to slow global warming. Trouble is, that acidified water doesn't stay
down in the deep: It rolls back to the surface along the West Coast and other
upwelling zones.
These nutrient-rich upwellings, full of sunken organic matter and
minerals, support a famously rich marine food chain, from microscopic plankton
to eight-ton killer whales. But if the waters become too acidic, they're
lethal to many shell-building creatures -- including young clams and oysters,
whose formative coverings are uniquely vulnerable in their first week or two of
life.
Even as the hatchery folks were struggling with acidifying water
inshore, scientists from Mexico ,
Canada , and the United States
were documenting similar changes in the waters further out. They found that the
upwellings operated on a time lag: The water rising from the depths today holds
CO2 absorbed about 30 to 50 years ago, when expansions in transportation,
industry, and other human activities began pushing increased amounts of carbon
into the atmosphere.
Because carbon emissions have continued rising since, future upwellings
are sure to be even more acidic. "We've mailed a package to
ourselves," says Oregon
State oceanographer Burke Hales, one of the scientists who conducted the
offshore research, "and it's hard to call off delivery."
Adaptation in action
Sue Cudd and Mark Wiegardt didn't have time to worry about future
deliveries; they had to protect their oysters now. That meant rethinking their
operation from the sea bottom up.
"We used to think cleaner water was better," Cudd says, and
so they purified and filtered relentlessly. But seawater chemistry is
devilishly complex and hard to manipulate. Cudd and Wiegardt decided they had
to learn to make better use of the water the ocean was giving them, but to do
that they needed to know precisely what was in it. Unfortunately, their
monitoring gear, like that of most in the industry, was minimal and crude. "We
were driving down the road blind," sighs Wiegardt.
Hales turned on the lights. In 2010, he lent Whiskey Creek
a gizmo that looks like a hospital heart monitor, but is actually a seawater
monitor that he built in his lab at Oregon
State . The colored squiggles
snaking across its twin screens measure the vital signs of the incoming water:
temperature, salinity, and dissolved carbon dioxide.
Cudd and Wiegardt call their monitor "the Burkalator" and
watch it like day-traders tracking their stocks. Once, Hales tried to borrow it
back for a research cruise. "No, you can't!" Cudd exclaimed. "If
you take it, I'll go out of business!"
The Burkalator revealed a striking pattern: Carbon dioxide and
acidity levels tended to peak in early morning. They fell off through the day
as the algae in the bay did what green plants everywhere do when the sun
shines: take up CO2 for photosynthesis. When night fell, the
photosynthesis ceased and the pattern reversed itself. The readings often
varied dramatically in a single day, Wiegardt said, from the aquatic equivalent
of as many as 800 parts per million of CO2 to as few as 200 parts, and from a
lethal pH of 7.5 to a luxurious pH 8.5. (Because pH is measured on a
logarithmic rather than an arithmetic scale, 7.5 is 10 times as acidic as 8.5.)
Thus informed, Cudd and Wiegardt could time their draws to take only
sweet, low-CO2 water, avoiding the sour morning blend. This entailed
compromises; to draw less often they had to reduce production and recycle used
water. But as Cudd says, "It's worse to put in bad water than to reuse
mucky water."
Hales and his colleagues installed another Burkalator at the Taylor hatchery in Washington .
They found that pH and CO2 levels varied just as widely there, but by depth
rather than time of day. Taylor 's
hatchery sits on a deep bay whose waters are stratified like a layer cake.
Cold, sour upwelled water tends to slide under the warmer, sweeter surface
water. Again, the solution was simple: Taylor
now draws from a shallow pipe rather than from deep water.
A temporary reprieve
The results are bracing. After a dire 2008 and 2009, Taylor has had its best years ever in 2010
and in the first half of 2011. Whiskey Creek isn't out of the woods -- Cudd and
Wiegardt had to resume buffering their water this spring, and the upwellings
this August have again made it difficult for them to find times when the water
is suitable for incubating baby oysters -- but they are shipping seed again.
"Here's 2 million oyster larvae," Cudd says, showing me a
swatch of white muslin wrapped around a gob of what looks like black sand.
"I just shipped 40 million this morning." She has even volunteered to
send 10 million larvae to help replenish a Japanese hatchery ravaged by the
March tsunami. That same hatchery helped supply the West Coast oyster
industry's original seed decades ago.
The hatcheries crisis offers both a foretaste of how the seas are
changing due to acidification and a model for how industry and science can work
together to mitigate it, says Lisa Suatoni, a
National Resources Defense Council staff scientist working on the issue.
"It's our first good example of the potential economic impacts of ocean
acidification," she says. "And it's a perfect example of people adapting
to the crisis."
But even the scientists and hatchery operators who have collaborated in
this success admit that it's a stopgap. In the long run, only reducing carbon
emissions into the atmosphere will keep ocean acidification from getting worse
and threatening more shellfish.
Alan Barton, who diagnosed Whiskey Creek's chemistry problem, isn't
waiting around for that to happen. He wanted to get as far away from souring
seas as he could, so in late 2009 he left Oregon
to start an oyster hatchery on North Carolina 's
Intracoastal Waterway . "I looked at a map
of the world and tried to figure out where ocean acidification was least likely
to be a problem," he says. "I picked here -- and I was wrong."
Already, Barton sees the problems that nearly shut down the West
Coast's hatcheries settling in on the East, thanks both to local conditions
and, he believes, to bigger changes in the sea itself. That's good for his
business, at least in the short term; natural oyster beds have failed in many
East Coast estuaries, just as they did on Willapa Bay, and Eastern oystermen
are turning to hatcheries like his for seed.
But his current success will be cold comfort if carbon emissions don't
abate and the sea undergoes catastrophic change.
"I'm afraid the ocean will be dead long before we have to worry
about the other implications of global warming," Barton says quietly.
"I didn't believe any of this stuff three years ago. I was always
skeptical about our global models ... But ocean acidification is pretty cut and
dried for me now. You see it every day. You can't escape it."
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