Tag: acidity

Acidic Oceans Dissolving Shellfish Industry

  • Oceanographer Richard Feely says the shellfish industry is suffering in part because the more acidic seawater encourages the growth of a type of bacterium that kills oyster larvae.(Photo courtesy of the NOAA)

When carbon dioxide is released into the atmosphere, about a third of it absorbs into the ocean. That creates carbonic acid—the stuff in soda pop that gives it that zing.

That means seawater is becoming more acidic.

Scientists say this ocean acidification is starting to cause big problems for marine life. And Ann Dornfeld reports that could affect your dinner plans.

Transcript

When carbon dioxide is released into the atmosphere, about a third of it absorbs into the ocean. That creates carbonic acid—the stuff in soda pop that gives it that zing.

That means seawater is becoming more acidic.

Scientists say this ocean acidification is starting to cause big problems for marine life. And Ann Dornfeld reports that could affect your dinner plans.

Taylor Shellfish Farms has been growing oysters for more than a
century. And shucking them, one by one, by hand.

“An old profession. Y’know, they’ve tried for years to
find a way to mechanize it. There’s no way around it. Every oyster is
so unique in its size and shape.”

Bill Dewey is a spokesman for Taylor. The company is based in
Washington state. It’s one of the nation’s main producers of farmed
shellfish. Dewey says if you order oyster shooters in Chicago, or just
about anywhere else, there’s a good chance they came from Taylor.

But in the past couple of years, the company has had a hard time
producing juvenile oysters – called “seed.”

“Last year our oyster larvae production was off about 60
percent. This year it was off almost 80 percent. It’s a huge impact to
our company and to all the people that we sell seed to.”

Shellfish growers throughout the Pacific Northwest are having similar
problems with other kinds of oysters, and mussels, too. They suspect a
lot of it has to do with ocean acidification.

Richard Feely is a chemical oceanographer with the National Oceanic
and Atmospheric Administration. He says when the pH of seawater drops
too low, it can hurt marine life.

“What we know for sure is that those organisms that
produce calcium carbonate shells such as lobsters, and clams and
oysters, and coral skeletons, they generally tend to decrease their
rate of formation of their skeletons.”

Feely says it looks like acidified waters are affecting oysters
because their larvae build shells with a type of calcium carbonate,
called aragonite, which dissolves more easily in corrosive water.

The more acidic seawater also encourages the growth of a type of
bacterium that kills oyster larvae.

Feely says the changes in the ocean’s pH are becoming serious. He
recently co-published a study on the results of a 2006 research cruise
between Hawaii and Alaska. It was identical to a trip the researchers
took in 1991. They found that in just 15 years, the ocean had become
five to six percent more acidic as a result of man-made CO2.

“If you think about it, a change of 5% in 15 years is a
fairly dramatic change. and it’s certainly humbling to see that in my
lifetime I can actually measure these changes on a global scale. These
are very significant changes.”

A couple years ago, Feely gave a talk at a conference of shellfish
growers. He explained the impact ocean acidification could have on
their industry. Bill Dewey with Taylor Shellfish Farms was there.

“All these growers were walking around with all these
really long faces, just very depressed. I mean it was a very eye-opening presentation and something that’s definitely had growers
paying attention since, that this could be a very fundamental problem
that we’re going to be facing for a long time to come.”

Dewey calls shellfish growers the “canary in the coalmine” for ocean
acidification.

Scientists say if humans don’t slow our release of CO2 into the
atmosphere, shellfish may move from restaurant menus into history
books.

For The Environment Report, I’m Ann Dornfeld.

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CO2 Eats at Ocean Creatures

  • Healthy Reef Systems May Be a Thing of The Past(Photo courtesy of Mikael Häggström)

Some scientists think we might be headed for a mass extinction event
in the oceans. When carbon dioxide gets released into the atmosphere,
a lot of that CO2 soaks into the oceans. That makes the water more
acidic. When the pH gets too low, it dissolves the skeletons of
animals like coral and mussels. Ann Dornfeld reports:

Transcript

** The story as originally broadcast incorrectly referred to the publication as “Natural Geoscience.” It should be “Nature Geoscience.”

Some scientists think we might be headed for a mass extinction event
in the oceans. When carbon dioxide gets released into the atmosphere,
a lot of that CO2 soaks into the oceans. That makes the water more
acidic. It can dissolve the skeletons of
animals like coral and mussels. Ann Dornfeld reports:

Fifty-five million years ago, a mass extinction happened when the
oceans became too acidic.

Richard Feely is a chemical oceanographer for the National Oceanic and
Atmospheric Administration. He says that today’s ocean acidification
is happening too quickly for many species to adjust.

“Over the last 200 years we’ve seen a 30-percent increase in acidity
of the oceans, and about six percent of that increase of acidity of
the oceans has been in the last 15 years.”

Researchers at the University of Bristol in England ran simulations of
the acidification processes 55 million years ago and today. They found
that acidification is happening ten times faster these days than it
did before the prehistoric mass extinction.

That could mean that if we don’t slow our release of CO2 into the
atmosphere, life in our oceans could crash within a century or two.
The study is published in the journal of Nature Geoscience.

For the Environment Report, I’m Ann Dornfeld.

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Clearing Up Cap-And-Trade

  • In cap-and-trade, businesses can purchase the right to pollute from other companies that reduce their emissions more than they need to. (Photo courtesy of the US EPA)

Congress is considering restricting
carbon emissions causing climate
change with a cap-and-trade scheme.
But, recent polls show only a handful
of people have heard of cap-and-trade.
Even fewer understand what it is.
Lester Graham reports cap-and-trade
is not new:

Transcript

Congress is considering restricting
carbon emissions causing climate
change with a cap-and-trade scheme.
But, recent polls show only a handful
of people have heard of cap-and-trade.
Even fewer understand what it is.
Lester Graham reports cap-and-trade
is not new:

We’ve been using the market-based tool to reduce other pollution.

Frank O’Donnell is with the environmental group Clean Air Watch. He says ‘remember acid rain?’ The government ‘capped’ the pollutants causing acid rain. And then came the ‘trade’ part.

“Sources can either reduce their emissions further or purchase the right to pollute from other companies that reduce their emissions more than they need to.”

O’Donnell says that cap-and-trade was cheaper than anybody predicted, and it reduced acid rain. But it didn’t eliminate it.

“And the reason is that the cap-and-trade target was essentially a politically-driven target. It was not one based fully on science.”

In fact, the US EPA is now proposing cutting acid rain pollutants more.

O’Donnell thinks a cap-and-trade scheme for carbon emmissions could be far more susceptible to political maneuvering.

For The Environment Report, I’m Lester Graham.

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Oceans Getting More Acidic

  • The research team collects several samples from each stop along the route to measure the chemical composition of the ocean water. (Photo by Ann Dornfeld)

We hear a lot about carbon dioxide in the atmosphere. But half of all man-made CO2 is stored in the world’s oceans. When CO2 mixes with water, it increases the oceans’ acidity. As Ann Dornfeld reports, that acidification is moving closer toward the oceans’ fragile coastal areas:

Transcript

We hear a lot about carbon dioxide in the atmosphere. But half of all man-made CO2 is stored in the world’s oceans. When CO2 mixes with water, it increases the oceans’ acidity. As Ann Dornfeld reports, that acidification is moving closer toward the oceans’ fragile coastal areas:


If you’ve ever wondered why sparkling water tastes tangy, instead of just bubbly – it’s because of carbonic acid. That’s what’s produced when carbon dioxide is added to water. Some of the CO2 in the world’s oceans is natural, from things like decaying algae. But the oceans also soak up CO2 produced by cars and factories. Once CO2 is absorbed into the ocean, it sinks to the coldest, deepest water for long-term storage.

Chemical oceanographers at Oregon State University are monitoring the chemical composition of the Pacific Ocean to see where the carbon is being stored. On a research vessel several miles off the coast, they lower a series of bottles down to the ocean floor on a winch.


(sound of winches)


Scientists have expected that upwellings would eventually bring some of that CO2 to the coastal zones that are home to a huge array of marine life. They thought it would take a century or more. But a recent study, published in the journal Science, found acidic water fewer than 20 miles off the Pacific Coast.

Grad student Rachel Holzer says that’s alarming.


“The ocean is normally at a very stable pH. It is a buffered system, which means it is not very easy for the pH to change. But recently there’s been evidence that ocean acidification is happening, meaning that the pH is dropping. And that can be very harmful to biological life of all different types.”


Corrosive water can dissolve the calcium carbonate shells of barnacles, mussels, oysters and clams. Coral reefs are also calcium carbonate. So are a lot of planktonic species, including terrapods. Those make up about half of the diet of young salmon.

Burke Hales co-authored the latest study. He’s an Associate Professor of Chemical Oceanography at Oregon State.


“The question is how are these organisms going to respond, you know? Do their shells dissolve, do they just not grow as quickly? If their shells are negatively impacted, are the organisms themselves negatively impacted? And if the organisms are negatively impacted, how does that cascade through the food web?”

Hales says stopping ocean acidification would be extremely difficult, if not impossible.


“There are people who have talked about going out in the ocean and spraying sodium carbonate pellets into the water, which would dissolve and neutralize some of the carbonic acid. Sort of like when you take a Tums, that’s the active ingredient in Tums is calcium carbonate. That’s one idea that’s been proposed. It’s really, really speculative that that would work.”


What’s more, Hales says the process of hauling all of that ocean antacid out to sea and dispersing it could produce as much CO2 as it would neutralize.


“It is depressing. We wish things weren’t this way and moving sort of irreversibly towards worse conditions. But we also know that the oceans do have a lot of ability to adapt. And what we don’t know yet is exactly how this is gonna play out.”


One thing scientists do know is that the acidification has just begun. The corrosive water they found right off the Pacific Coast was from carbon dioxide released about 50 years ago. And over the last half century, CO2 production has only increased.


For the Environment Report, I’m Ann Dornfeld.

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Co2 Turning Ocean Acidic

  • Researchers have found that the Pacific Ocean is becoming increasingly acidic as a result of CO2 emissions (Photo by A. Kalvaitis, courtesy of NOAA)

The Pacific Ocean is becoming more acidic.
The corrosive water could start dissolving shells
and coral. The problem is largely caused by carbon
dioxide emitted by cars and power plants. As Ann
Dornfeld reports, researchers say the problem is
happening faster than they expected:

Transcript

The Pacific Ocean is becoming more acidic.
The corrosive water could start dissolving shells
and coral. The problem is largely caused by carbon
dioxide emitted by cars and power plants. As Ann
Dornfeld reports, researchers say the problem is
happening faster than they expected:

Scientists have known for a long time that the world’s oceans are becoming corrosive
from so much man-made CO2. Carbon dioxide dissolves into the ocean, and forms
carbonic acid.

The corrosive water is concentrated in deep, cold parts of the ocean. Scientists had
predicted it would approach the vulnerable coastal zones in about a century. So they
were alarmed to find the acidity just a few miles off the California coast.

Burke Hales is a chemical oceanographer. He says this corrosive water could break
down the calcium carbonate in coral and shells.

“So we’re talking about things like barnacles and oysters and mussels and
clams. And some planktonic organisms form calcium carbonate shells, as well.”

Researchers say the acidification approaching the coasts is from CO2 that was emitted
50 years ago. That means we’re just at the start of increasingly acidic oceans.

For The Environment Report, I’m Ann Dornfeld.

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Major Dock Corrosion Stumps Officials

  • The Duluth Seaway Port Authority's bulk cargo dock is typical of many in the port. Officials are troubled by corrosion appearing on the docks in the harbor - the steel is corroding much faster than normal. (Photo by Bob Kelleher)

Corrosion is eating away at the steel walls that hold one of the Great Lakes’ busiest harbors together. The corrosion is unlike anything known to be happening in any other Great Lakes port. But other port officials are being encouraged to take a closer look at their own underwater steel. The Great Lakes Radio Consortium’s Bob Kelleher reports:

Transcript

Corrosion is eating away at the steel walls that hold
one of the Great Lakes’ busy harbors together. The
corrosion is unlike anything known to be happening in
any other Great Lakes port. But other port officials
are being encouraged to take a closer look at their own
underwater steel. The Great Lakes Radio Consortium’s
Bob Kelleher reports:


Some kind of corrosion is eating away at the Duluth
Seaway port’s docks. The docks are those long
earth-filled metal rectangles where ships from around
the world tie up to load and unload. Those docks are
lined with sheets of steel, and the steel is rusting
away. Jim Sharrow is the Duluth
Seaway Port Authorities Facilities Manager.


“It’s corroding quickly – much faster than people expect
in fresh water. And our main concern is that we’ll lose
the integrity and the strength of the dock long before
expected, and have to do steel replacement at $1,500 or
more per lineal foot, much earlier than ever would have
been expected.”


Corrosion should be a slow process in Duluth’s cold
fresh water. But, Sharrow says, there’s evidence it’s
been happening remarkably quickly for about thirty years.


“What we seem to see here is corrosion that started in
the mid 1970s. We have steel that’s 100 years olds
that’s about as similarly corroded to steel that is 25
to 30 years old.”


It’s a big problem. There’s about thirteen miles of
steel walls lining docks in the harbor that serves
Duluth, Minnesota and Superior, Wisconsin. There’s half
again as many feet of wooden docks, held together with
steel pins. There’s corrosion on the legs of highway
bridges and the giant
steel ore docks that ship millions of tons of taconite
– a type of iron shipped to steel mills in Gary,
Indiana and Cleveland, Ohio.


“We characterize this as a 100-million dollar problem in
the harbor. It’s a huge problem, and what is so odd
about this is that we only see it happening in the
navigational area of the Duluth-Superior Harbor.”


The harbor links the St Louis River with Lake Superior.
Go a few miles up the river and there’s little corrosion
. So it doesn’t seem like the problem’s there. But, back
in the harbor, at the current rate of corrosion, Sharrow
says, the steel will fail quickly.


“I figure that in about 10 years at the current rate,
we will have to start replacing steel.”


“Particularly marginal operators could decide rather
than repair their docks it would be better for them to
go out of business, and we’re hoping that that isn’t
the case here.”


While the cause is a mystery, there’s no shortage of
theories. It could have something to do with stray
electrical voltage; water acidity; or the kinds of
steel manufactured in recent years. Chad Scott
discovered the corrosion in the late 1990’s. He’s an
engineer and a diver. Scott suspects
a micro-biological connection. He says there might be
something growing in small round pits that form on the
steel.


“We cleaned up the water. That’s the main thing –
that’s one of the main changes that’s happened since
the 70s, is we’ve cleaned up our water. We’ve cleaned
up our harbor, which is a good thing. But, when we
cleaned things up we also induced more dissolved oxygen
and more sunlight can penetrate the water, which tends
to usually promote more growth – more marine
microbiology growth.”


A team of experts met in Duluth in September to share
ideas. They came from the U.S. Navy, The Army Corp of
Engineers, and Ohio State University. And they agreed
there’s something odd going on – possibly related to
microbes or water chemistry. They also recommend that
other Great Lakes ports take a closer look at their
underwater steel. Scott says they at least helped
narrow the focus.


“We have a large laundry list right now. We want to
narrow that down and try to decide what is the real
cause of this corrosion. And these experts, hopefully,
will be able to get us going on the right direction,
so we can start doing testing that will identify the
problem.”


With the experts recommendations in hand, port
officials are now planning a formal study. If they
do figure out the cause, then they’ve got to figure
out how to prevent it. They’re in a race with
something, and right now they don’t even know with
what.


For the Great Lakes Radio Consortium, I’m Bob Kelleher.

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Study: Acid Rain Depletes Soil Nutrients

Acid rain isn’t a new threat to the environment. But its effect on trees and soils has been a point of debate. Now, a new study supports the theory that acid rain can deplete nutrients in forest soil. The Great Lakes Radio Consortium’s Corbin Sullivan has more:

Transcript

Acid rain isn’t a new threat to the environment. But its effect on trees and soils has
been a point of debate. Now, a new study supports the theory that acid rain can
deplete nutrients in forest soil. The Great Lakes Radio Consortium’s Corbin Sullivan
has more:


Acid rain is caused by emissions mostly from coal-fired power plants. It’s linked to “dead”
lakes and streams that have become too acidic for fish and other organisms.


But a new study published in the Soil Science Society of America Journal says the
addition of even a small amount of acid to forest soils can deplete minerals needed for
plant and animal survival.


Ivan Fernandez is the lead author of the study. He says the study showed the loss of
several nutrients, but he’s most concerned with calcium loss.


“Calcium both reduces the toxicity of bad things as well as being a required essential nutrient.
If you lose too much calcium, you can have direct nutrient deficiencies.”


Fernandez says when minerals like calcium and magnesium are lost the result is
slower plant growth. He also says the loss of these minerals can lead to poor water quality.


For the Great Lakes Radio Consortium, I’m Corbin Sullivan.