seawater along West coast getting more acidic
Last updated May 27, 2008 5:17 p.m. PT
Rising acidity of seawater could disrupt NW food chains
SEATTLE -- Puget Sound faces an
uncertain future due to the increasing acidity of seawater, a panel of
marine scientists said Tuesday. The changes are coming more rapidly
than expected, and could disrupt food chains and threaten Washington's
The acidic seawater is moving closer to
shallow waters containing the bulk of marine life, according to an
article this month in the journal Science. The increasingly corrosive
water threatens the survival of many organisms, from microscopic plants
and animals at the base of the food chain to shellfish, corals and the
young of some marine species.
The latest research indicates acidic water is appearing along the Pacific Coast decades earlier than expected.
The research involved experts from Oregon, California and Canada.
The acidified water does not pose a threat to humans, but it could dissolve the shells of clams, oysters and other shellfish.
of the article's authors, Christopher Sabine, told Sen. Maria Cantwell,
D-Wash., - who convened Tuesday's hearing - and Rep. Jay Inslee, also
D-Wash., about watching small marine snails placed in water of similar
acidity to that recorded last summer off the northern California coast.
"We actually saw the shells dissolving off these living organisms. They
were dissolving off the terapods as they were swimming around," Sabine
said. Such creatures comprise as much as 40 percent of the Pacific king
Global ocean currents make the Pacific
Northwest's coastal ecosystems particularly vulnerable to
acidification's effects, Sabine said. A worldwide "conveyor belt" very
slowly carries colder water from the North Atlantic to the North
Pacific. Along the way, the water accumulates carbon dioxide from dead
organisms, so it naturally has a higher carbon dioxide concentration
before man-made carbon dioxide is added. A process known as
'up-welling' drags this water into shallower, coastal areas.
long as CO2 continues to increase in the atmosphere, the oceans will
continue to absorb that," Sabine said. "What we're seeing is only going
to get worse."
The panel members said they did not know exactly how acidification will affect Puget Sound and other Northwest coastal waters.
know very little about the biological effects of acidification on the
West Coast," said Terrie Klinger, of the University of Washington's
School of Marine Affairs. However, research has demonstrated that there
will be early and strong effects in Northwest coastal ecosystems, she
"We won't see a total collapse in food chains, but we
will see substitutions," Klinger said. "We may end up with food chains
or food webs that are highly undesirable and not productive for the
means that we use them today."
Corrosive water could be
disastrous for Washington state's shellfish industry, noted one panel
member, Brian Bishop, owner of Little Skookum Shellfish Growers in
Shelton, Wash. Washington state produces 85 percent of all shellfish on
the West Coast, Bishop said.
"This acidity dissolves calcium
carbonate, which is the thing that shells are made out of. If diatoms,
corals, clams and oysters succumb to this it not only wipes out the
shellfish industry but potentially the entire marine food chain," said
Bishop, a fifth-generation shellfish harvester.
His family-owned farm has 27 year-round employees and around $2.8 million in annual sales.
"If we can't grow our shellfish, the bank will foreclose on the mortgage. We'll lose our farm, our homes," Bishop said.
Koenings, director of Washington's Department of Fish and Wildlife,
called for "precautionary resource management," such as the recently
renegotiated Pacific Salmon Treaty. Current management schemes rely on
historic trends that are not applicable, given changing climate
conditions, Koenings said.
"In light of all this uncertainty
we just need to cool; we need to cut the harvest on certain species
down to a level that we think is sustainable," Koenings said. Previous
rates of harvest for some species, such as some salmon, are not
sustainable now because of decreased productivity, he noted.
Inslee stressed that ocean acidification is different from climate change.
are people who still want to argue about climate change. Let them have
that argument, but there's no argument about ocean acidification,"
Inslee said afterward.
Congress has taken small steps toward
reducing carbon production, Inslee said. But a carbon cap-and-trade
system - which allows companies or other groups to emit a certain
amount of carbon and trade any excess allowance with other carbon
producers - is Inslee's goal.
"At least by next fall I believe we'll have a cap and trade system in place," he said.
hearing was not part of any upcoming legislation, but rather designed
to raise awareness of the issue in the Senate, said Ciaran Clayton, a