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Ian McColgin
04-08-2010, 10:23 PM
An important set of observations.

Published on Thursday, April 8, 2010 by CommonDreams.org

The Last Oyster Haul?

by Brendan Smith

Thanks to greenhouse gas emissions, it's looking like my days as a commercial fisherman are numbered.

I've been working the sea on-and-off my whole life. At 15 years old I quit high school to work the lobster boats out of Lynn, MA; later I fished cod and crab boats on the Bering Sea. As over-fishing decimated the cod stocks, I headed back home to Newfoundland to try my hand as a fish farmer growing halibut and salmon.

Now I'm an oyster man, growing 100,000 organic oysters a year on a 40-acre plot in the Long Island Sound. I see myself as a new breed of green fisherman, who have shifted from hunter-gatherers trolling the seas in search of declining fish stocks, to ocean-based farmers, sustainably growing shellfish on small plots of ocean acreage for local markets. (Oysters rank as one of the top "super green seafoods" by the Environmental Defense Fund.)

But now, just as I've regained my green sea legs, scientists tell me that in the coming decades I won't be able to make a living growing oysters anymore. They tell me greenhouse gas emissions from burning fossil fuels are turning the oceans acidic, and oysters, already fickle little creatures, are likely to be the first victims.

Here's how the marine biologists tell me the process works: Oceans absorb about 25 percent of the world's greenhouse gases from human activities. The problem is that too much CO2 absorption also raises water's acidity. Increased acidity reduces carbonate -- the mineral used to form the shells and skeletons of many shellfish and corals. The effect is akin to osteoporosis, slowing growth and making shells weaker. If pH levels drop enough, the shells will literally dissolve.

The acidification of the ocean today is larger and faster than anything scientists can find in the fossil record over the past 65 million years. According to a recent study in the journal Natural Geoscience , current ocean acidification is taking place at ten times the rate that preceded the mass marine extinction 55 million years ago.

Oysters and other shellfish are expected to be some of the first victims of ocean acidification. Researchers at Stony Brook University's School of Marine and Atmospheric Sciences found that even minor increases in ocean acidity have significant, detrimental effects on the growth, development and survival of hard clams, bay scallops and oysters. Scientists already suspect that acidic water is responsible for killing several billion oyster, clam and mussel larvae that were being raised at the Whiskey Creek Shellfish Hatchery on the Oregon coast in the summer of 2008.

But it's not just my oysters and livelihood that are imperiled. Shellfish and other vulnerable species function as crucial links for entire ecosystems in the ocean. According to the NRDC :

The new chemical composition of our oceans is expected to harm a wide range of ocean life. The resulting disruption to the ocean ecosystem could have a widespread ripple effect and further deplete already struggling fisheries worldwide... A more acidic ocean could wipe out species, disrupt the food web and impact fishing, tourism and any other human endeavor that relies on the sea.

Commercial fishermen have conflicted hearts. We're famously independent, often wary of government regulation. We have traditionally had a complex, often combative relationship with the environmental movement. But at the same time, we also have a deep respect and love for the sea. Our lives, our livelihoods, are held at the mercy of natural forces more than almost any other occupation.

Politicians try to cast workers as not caring about protecting ocean resources and the perilous effects of greenhouse gases. They say the coming crisis is too far off and we're more fearful about environmental policy destroying jobs. Exactly the opposite. Protecting my life and livelihood requires protecting the oceans and planet.

# # #

Brendan Smith is an oysterman and labor activist. He is co-founder of the Labor Network for Sustainability and Global Labor Strategies , as well as a consulting partner with the Progressive Technology Project .

skuthorp
04-08-2010, 10:32 PM
I keep remembering that quote about the world ending "not with a bang, but with a whimper".

LeeG
04-08-2010, 11:21 PM
maybe in 500yrs the human population will have settled down to a sustainable number since most of the oil and coal will be used up.

Kaa
04-09-2010, 12:25 AM
Scientists already suspect that acidic water is responsible for killing several billion oyster, clam and mussel larvae that were being raised at the Whiskey Creek Shellfish Hatchery on the Oregon coast in the summer of 2008.

That sounds like bull**** to me.

http://tillamookheadlightherald.com/main.asp?SectionID=8&SubSectionID=8&ArticleID=9550

Kaa

Phil Heffernan
04-09-2010, 12:46 AM
Am I right in assuming, Kaa, that this is another example of the charade of global climate change?

PH

seanz
04-09-2010, 01:27 AM
What do the Walrus and the Carpenter have to say for themselves now?

Kaa
04-09-2010, 02:10 AM
Am I right in assuming, Kaa, that this is another example of the charade of global climate change?

I don't know -- to me it looks like an example of discussing a real process (oceans do acidify) but in deliberately vague and scary terms. Check the article -- he doesn't actually say *when* all these bad things will happen. He says "coming decades" which could mean anything from 20 to 200 years.

The larvae die-off in Oregon is one of hard facts in this article, and guess what -- he gets it wrong.

Kaa

shamus
04-09-2010, 03:27 AM
Win some lose some: good for lobsters prawns and various other crustaceans.
http://www.whoi.edu/page.do?pid=11636&tid=282&cid=52990

Ian McColgin
04-09-2010, 07:13 AM
Actually, the die-off in Oregon is not perfectly understood but the larvae cause was disproven a couple years before the rather obscure tourist rag picked up the story.

From the Seattle Times, June 15, 2009

(picking up a couple paragraphs into the story)

Researchers at first blamed an explosion of Vibrio tubiashii, an ocean-borne larvae-killing bacteria. When researchers sampled the marine waters that get sucked directly into the hatcheries from the sea, they found bacteria counts nearly 100 times above normal. Even after installing extensive microbe-killing ultraviolet water-treatment systems, larvae died.
Then they noticed the water's pH — the scale measuring acidity and alkalinity — sometimes dropped below normal, becoming more acidic.
Seawater typically is slightly alkaline, but when oceans absorb carbon dioxide from the atmosphere — as they have by the hundreds of billions of tons since the Industrial Revolution — they become more corrosive.
Climate modelers predicted greenhouse gases would make marine waters more acidic by century's end. They expected to notice it first in deep water, some of which hasn't circulated to the surface in 1,500 years and has therefore accumulated more atmospheric carbon dioxide. And deep waters already run higher in carbon dioxide because dying plants, animals and fish sink and decay.
But two years ago, oceanographers Richard Feely and Chris Sabine, both with the National Oceanic and Atmospheric Administration's Pacific Marine Environmental Laboratory in Seattle, found more acidified waters already reaching the surface.
The north winds that blow off Washington's coast push marine surface waters off shore. Those waters are replaced by the icy-cold, more corrosive seawater welling up from hundreds of meters below.
Throughout 2008, researchers at Oregon's Whiskey Creek Shellfish Hatchery noticed a trend: Their die-offs tended to come after north winds pushed those very same deep waters into the pipes that feed the hatchery.
"There seems to be a strong correlation," Feely said.

http://seattletimes.nwsource.com/html/localnews/2009336458_oysters14m.html

Kaa
04-09-2010, 12:17 PM
Actually, the die-off in Oregon is not perfectly understood but the larvae cause was disproven a couple years before the rather obscure tourist rag picked up the story.

From the Seattle Times, June 15, 2009

(picking up a couple paragraphs into the story)

Researchers at first blamed an explosion of Vibrio tubiashii, an ocean-borne larvae-killing bacteria. When researchers sampled the marine waters that get sucked directly into the hatcheries from the sea, they found bacteria counts nearly 100 times above normal. Even after installing extensive microbe-killing ultraviolet water-treatment systems, larvae died.
Then they noticed the water's pH — the scale measuring acidity and alkalinity — sometimes dropped below normal, becoming more acidic.
Seawater typically is slightly alkaline, but when oceans absorb carbon dioxide from the atmosphere — as they have by the hundreds of billions of tons since the Industrial Revolution — they become more corrosive.
Climate modelers predicted greenhouse gases would make marine waters more acidic by century's end. They expected to notice it first in deep water, some of which hasn't circulated to the surface in 1,500 years and has therefore accumulated more atmospheric carbon dioxide. And deep waters already run higher in carbon dioxide because dying plants, animals and fish sink and decay.
But two years ago, oceanographers Richard Feely and Chris Sabine, both with the National Oceanic and Atmospheric Administration's Pacific Marine Environmental Laboratory in Seattle, found more acidified waters already reaching the surface.
The north winds that blow off Washington's coast push marine surface waters off shore. Those waters are replaced by the icy-cold, more corrosive seawater welling up from hundreds of meters below.
Throughout 2008, researchers at Oregon's Whiskey Creek Shellfish Hatchery noticed a trend: Their die-offs tended to come after north winds pushed those very same deep waters into the pipes that feed the hatchery.
"There seems to be a strong correlation," Feely said.

http://seattletimes.nwsource.com/html/localnews/2009336458_oysters14m.html

Color me not impressed.

First, "There also isn't sophisticated enough equipment in place to get precise pH readings." So, um, you don't even know whether the ocean water coming in is acidified or not -- but you're claiming GW-caused acidification caused the larvae die-off..? :D

Second, "...deep water, some of which hasn't circulated to the surface in 1,500 years and has therefore accumulated more atmospheric carbon dioxide." Come again? So, there's been more CO2 in the atmosphere for the last few decades -- and because of that deep water "which hasn't circulated to the surface in 1,500 years" is more acidic? Someone's brain switched off -- or maybe it wasn't on to start with :-)

So let me see. The bacteria counts are 100 times more than normal. There's a low-oxygen dead zone nearby. And there's correlation with upswellings of deep water which hasn't been in contact with the atmosphere for centuries and which is also low in oxygen. Now, what do we blame for larvae die-off?

Correct! We blame anthropogenic global warming :D

Kaa

Ian McColgin
04-09-2010, 12:34 PM
Firstly, I was wrong about the date of the article Kaa cited in post #4. It was May 20, 2008.

At that time it was thought that a bacterium was killing the shellfish larvae. One had to parade past a good number of more recent stories from more reputable newpapers to find this. At any rate, the article’s hope that a filtration system that kept the bacteria out was developed and the shellfish larvae still died.

That’s one of several reasons I looked to a more up to date source, no matter what it said, rather than plundered to the past to find a source that agreed with my assumptions.

Changes in the ocean, current flows due to more cold water entering as the ice cap melts shifting the behaviors of the Japan and Bermuda currents and all that, are part of the complexities of global climate change. Keeping an open mind is part of the scientific process. Since knowledge is always in some - actually many -respects incomplete, we are always in some ways wrong. Just as the theory that bacterium were killing the shellfish larvae proved wrong.

Kaa
04-09-2010, 02:13 PM
The deep water being referred to here is more acidic, but ain't nobody trying to claim that present levels of CO2 are the cause.... that's was a little bit of misinterpretive sleight of hand, on your part.

Wouldn't it be useful to, y'know, read the article in question before pronouncing judgments on sleight of hand...


They suspect water that rises from deep in the Pacific Ocean — icy seawater that surges into Willapa Bay and gets pumped into seaside hatcheries — may be corrosive enough to kill baby oysters. If true, that could mean shifts in ocean chemistry associated with carbon-dioxide emissions from fossil fuels may be impairing sea life faster and more dramatically than expected.and

Climate modelers predicted greenhouse gases would make marine waters more acidic by century's end. They expected to notice it first in deep water, some of which hasn't circulated to the surface in 1,500 years and has therefore accumulated more atmospheric carbon dioxide.So yeah, the article *is* trying to claim that AGW is making deep waters more acidic. No, that doesn't make sense. No, that didn't stop the author.


You might do well to switch on the rest of yours. A few lobes are apparently unpowered.

Haven't felt the need so far :-P



However, I do know this: when you struggle hard to find reasons to dismiss the possibility of global warming, you're not merely contesting the notion, you're actually stepping outside the bounds of science. You can join SamF and the other scientific reprobates in the corner now :)

Um, are you talking to yourself again?

Oh, and do tell what the bounds of science are and how do you know where they are located... :-)

Kaa

Ian McColgin
04-09-2010, 02:27 PM
Ummmm Kaa, before you embarrass yourself further read up a little on how climate change relates to shrinking ice caps relates to ocean current changes.

Kaa
04-09-2010, 02:29 PM
Ummmm Kaa, before you embarrass yourself further read up a little on how climate change relates to shrinking ice caps relates to ocean current changes.

I'm OK with embarrassing myself :-)

Do you have some specific statement of mine in mind..?

Kaa

Ian McColgin
04-09-2010, 02:49 PM
Kaa, I already mentioned that the tourist rag you cite in post #4 was not only out of date but is not even on the first page of any way I could google up Whiskey Creek die-off, etc. Perhaps you used a different search term to go right to outdated information about the cause. But let’s start there. Do you still figure it’s the bacteria?

If yes, there’s little I can do for you. If no, do you see that the pH issue as reported is due to changes in ocean currents?

If yes, then do these changes have aught to do with climate change? Personally I find it hard to call massive ocean current changes anything other than climate change. Perhaps you believe that climate change is not caused or accelerated by human industrial actions. Maybe Three Gorges won’t tip Earth a degree either.

GIven the way Smith wrote, one might conclude that the acidification of Long Island Sound and of the ocean waters of the eastern North Pacific both have one cause - acid rain. Well, we know that in the Sound that is a cause that is above the acidification of the general North Atlantic. I don’t know how much the petro-pollution falling in the Pacific with China’s industrialization is contributing compared with the changes in ocean currents. Smith’s summary could have clarified the relative roles of these two human driven causes in a way that did not confuse people determined to drink with the petro-industry.

Kaa
04-09-2010, 02:58 PM
But let’s start there. Do you still figure it’s the bacteria?

Um, how would I know? I haven't studied the issue. All I claim is that attempts to pin the blame on AGW look ridiculous to me.


If no, do you see that the pH issue as reported is due to changes in ocean currents?

That's not what the article in the Seattle Times says.


GIven the way Smith wrote, one might conclude that the acidification of Long Island Sound and of the ocean waters of the eastern North Pacific both have one cause - acid rain.

There is NO mention of acid rain in Smith's article. Why might one conclude that?

You do understand the difference between acid rain and CO2-driven acidification of the oceans, don't you?

Kaa

LeeG
04-09-2010, 03:31 PM
the oyster population in the Chesapeake has plummeted long before global warming had an impact on the water. Maybe global warming will be as good as any other condition that helped trip an extinction event.

Ian McColgin
04-09-2010, 03:37 PM
kaa is correct. Acid rain was not mentioned. I understand how complex and dynamic CO2 oceanic absorption and emission can be, all depending on latitude and depth etc. I recalled all on my own a bit about the interplay of acid rain affecting the carbon cycle and managed to rumble it all together. I apologize. I am still having double vision and so squint briefly and depend more on an often faulty memory.

My simplest central point is that Kaa dismissed Smith’s essay with a cite to a disproved cause for the shellfish die-offs in the Pacific Northwest. The later studies tie the problem to changes in the great oceanic carbon sink.

Every resourse depletion takes individual analysis. Some are due to upland pollution. Some to over-extraction. Some, like the Chesapeake, to both. Given that Bay’s water flow, one would expect oceanic pH changes to be a secondary later effect.

I guess the disagreement comes down to whether the phenomena in that set of issues is human affected or not. On that matter, Kaa has shown himself as willing to change his mind on that as I am now.

shamus
04-09-2010, 04:02 PM
I notice that surface testing at Mauna Loa has shown an annual change in pH of about -0.00186 mean over the last 20 years.
Article here http://www.nrdc.org/oceans/acidification/figures.asp

Kaa
04-09-2010, 04:09 PM
Thank you, Ian.


I notice that surface testing at Mauna Loa has shown an annual decrease in pH of about -0.00186 mean over the last 20 years.
Article here http://www.nrdc.org/oceans/acidification/figures.asp

Interesting article.

I wonder if there's any justification to modeling pCO2 and pH by linear models. My eyeball mark I sees a kink or a curve in the scatterplot.

http://www.nrdc.org/oceans/acidification/images/figure2.gif

Kaa

shamus
04-09-2010, 04:17 PM
CO2 absorption at the surface is affected by temperature and pressure too. ljb once gave a good explanation of this. I presume the R^2 of 0.2654 indicates that the pH is weakly correlated with atmospheric CO2, probably because of the temperature and pressure effects. Don't shoot me- it's a presumption- I'm willing to learn otherwise.