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.

Related Links

A Bog’s Goodbye

  • Greg Seymour, with the Ohio Department of Natural Resources, walking through Cranberry Bog (Photo by Christina Morgan)

It’s normal to want to protect special
places in nature. But in some cases, these
places are disappearing simply because of nature.
Christina Morgan reports on an ancient spot that
might disappear in our lifetime. The people who
love it want to save it, but they might have to
let it go:

Transcript

It’s normal to want to protect special
places in nature. But in some cases, these
places are disappearing simply because of nature.
Christina Morgan reports on an ancient spot that
might disappear in our lifetime. The people who
love it want to save it, but they might have to
let it go:

For four generations, J-me Braig’s family has visited a rare
site, a bog left behind by glaciers thousands of years ago.

“As a child, I used to go out there and play on it, with my
grandmother, and we would pick cranberries; my brother and I would play on it. ”

Braig says her grandmother used to take a boat out to the bog
in a lake in Ohio. Her grandmother made pies and wine with
the cranberries.

Braig is a lake historian who’s worried about the bog. That’s
because it’s shrinking.

But before we talk about why it’s shrinking, though, it’s important
to know what makes this tiny area special.

Webster’s dictionary defines a bog as soft, waterlogged
ground. This bog, Cranberry Bog, is soft and waterlogged.
But it’s not ground. There’s no dirt. The bog is a 10 acre
patch of sphagnum moss.

Most bogs surround a glacial lake. Instead, Cranberry Bog is
surrounded by a lake, and floating. Here’s what happened.

Nearly 200 years ago, crews digging in an ancient river bed
created a reservoir to feed the Ohio and Erie canal. The
reservoir filled, the mossy bog floated to the surface. How or
why it stayed, no one knows.

“An absolute oddity. It shouldn’t be here.”

Greg Seymour is with the Ohio Department of Natural
Resources. He says the ancient bog is home to likely the only collection
of plants of its kind in the world.

More than 150 plants, a
handful native to Canada. Nudged southward by the glacier,
the plants are tricked by the cool bog mat into thinking they
never left home.

The bog is shrinking for several reasons. Waves from passing
boats loosen the bog mat. Storms topple trees
which rip out chunks of the mat. But Seymour says the biggest
threat is the bog’s chemistry, which makes the site its own
worst enemy.

“The number one factor is going to be the chemical reaction
between the alkaline lake waters and the acidic bog.”

The pH balance is off – way off. Cranberry Bog is doomed to disappear, probably within 30
years.

But area historian J-Me Braig remains upbeat, saying ever
since she can remember, someone has had a scheme to save
Cranberry Bog.

And sure enough, there is a new group determined to preserve the
ancient bog.

George O’Donnell leads Friends of Cranberry Bog. He and
others think one way to generate interest in the site, is to inventory of all that the bog has to offer.
Such an inventory is being done by the bog’s neighbor 8 miles
to the north, Dawes Arboretum.

Tim Mason is the manager of natural resources there. He says even
if the inventory and other efforts to preserve the bog fail, they
have a plan B. Dawes created a restoration area where pieces
of Cranberry Bog that break off are placed.

“We can just hold on to what’s there. It takes thousands of
years for the peat moss material to grow; so to create that is something we would certainly not see in
our life times.”

Saving the bog – or just preserving its pieces – are a long shot.
Yet the efforts persist. Historian J-Me Braig is one of many people
who hope for success. But even Braig admits, after more than
10,000 years, Cranberry Bog has had a pretty good run.

For The Environment Report, I’m Christina Morgan.

Related Links

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.

Related Links

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.