Saturday, September 1, 2007

Ocean acidity--the next big climate thing


The next big thing in the
climate change debate is
the changing acidity of
the oceans.
Researchers in Hawai'i are
among scientists worldwide
who are tracking the slow
but apparently quite real
movement of the oceans from being slightly basic toward
being acidic.
The argument is that this is a direct result of the
increasing amounts of carbon dioxide in the atmosphere.
(This is going to get a little technical, but
essentially, carbon dioxide, which comes in part
from the burning of oil and coal, is a greenhouse gas.
It's a major cause of global warming. And while there
are still some folks out there debating whether 1. there
is global warming, or 2. whether that's a bad thing--there
is no real debate that 3. the percentage of carbon
dioxide in the atmosphere has increased dramatically
in the past century, and continues to rise.)
(When you mix carbon dioxide with water, you get a mild
acid. More carbon dioxide, a higher concentration of
acid. So at its simplest, that's what's going on with
the oceans—more carbon dioxide in the air, and the
oceans become more acid.)
The Center for Biological Diversity
(www.biologicaldiversity.org) has recently asked seven
coastal states, including Hawai'i, to act on this.
That's because these are the states most likely to
suffer from changing ocean acidity.
The organization has asked Alaska, Florida, Hawai'i,
Oregon, New Jersey, New York and Washington to declare
their coastal waters impaired under the Clean Water Act.
California was asked to do so earlier.
“Ocean acidification is quietly, lethally altering the
fundamental chemistry of the world's oceans. We must
act now to prevent global warming's evil twin, ocean
acidification, from destroying our ocean ecosystems,”
wrote Miyoko Sakashita, an attorney and head of the
center's oceans program.
Alkalinity or acidity is measured on a pH scale from
1 to 14, in which 1 is very acid and 14 is very
alkaline. Neutral is 7.

Lemon juice is quite acid, with a pH of 2.4, while
hand soap, which is alkaline, is about 9 or a little
more.

The oceans are slightly alkaline, at about 8. But with
the increasing carbon dioxide in the atmosphere,
oceanic pH has decreased by a little more than a tenth
of a point. It's not a lot, but nobody knows yet (lot
of research is getting started) at what point the
change begins causing reefs to decompose and sea
creatures' shells to stop forming.

Sakashita says the carbon dioxide is increasing so
rapidly that the oceans will change their pH faster
than species can evolve and adapt.
The Center for Biological Diversity hopes that the
Clean Water Act might be used as a lever to force
changes in the society's production of carbon dioxide.

“If ocean waters are listed (as impaired), the law would
require states to limit carbon dioxide pollution entering
the ocean waters under their jurisdiction,” Sakashita
said in a press release.


© 2007 Jan W. TenBruggencate

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