Climate Change Alters Ocean Chemistry

( -- Researchers have discovered that the ocean's chemical makeup is less stable and more greatly affected by climate change than previously believed. The researchers report in the December 12, 2008 issue of Science that during a time of climate change 13 million years ago the chemical makeup of the oceans changed dramatically. The researchers warn that the chemical composition of the ocean today could be similarly affected by climate changes now underway – with potentially far-reaching consequences for marine ecosystems.

"As CO2 increases and weather patterns shift, the chemical composition of our rivers will change, and this will affect the oceans," says co-author Ken Caldeira of the Carnegie Institution's Department of Global Ecology. "This will change the amount of calcium and other elements in ocean salts."

The research team, which included Caldeira, Elizabeth M. Griffith and Adina Paytan of the University of California, Santa Cruz, plus two other colleagues, studied core samples of deep oceanic sediment recovered from the Pacific Ocean Basin. By analyzing the calcium isotopes in grains of the mineral barite in different layers, they determined that between 13 and 8 million years ago the ocean's calcium levels shifted dramatically. The shift corresponds to the growth of the Antarctic ice sheets during the same time interval. Because of the huge volume of water that became locked up in the ice cap, sea level also dropped.

"The climate got colder, ice sheets expanded, sea level dropped, and the intensity, type, and extent of weathering on land changed," explains Griffith.

"This caused changes in ocean circulation and in the amount and composition of what rivers delivered to the ocean," adds Paytan. "This in turn impacted the biology and chemistry of the ocean."

Calcium-bearing rocks such as limestone are the largest storehouse of carbon in the Earth's carbon cycle because they are primarily made up of calcium carbonate. "The ocean's calcium cycle is closely linked to atmospheric carbon dioxide and the processes that control seawater's acidity," says Caldeira. Acidification of seawater is already a growing threat to coral reefs and other marine life.

"What we learned from this work is that the ocean system is much more sensitive to climate change than we have previously appreciated," says Griffith. "We thought that the concentration of calcium, which is a major element in seawater, would change slowly and gradually over tens of millions of years. But what our data suggests is that there could be a more dynamic relationship between climate and ocean chemistry, which can sometimes result in rapid biogeochemical reorganization."

"We see here how dynamic the climate-ocean system is and that the responses to change are not always what we would expect" says Paytan. "We need to keep this in mind when considering future climate and other anthropogenic changes, like ocean acidification, and their impact on the ocean and ocean resources."

Article: A dynamic marine calcium cycle during the past 28 million years. Elizabeth M. Griffith, Adina Paytan, Ken Caldeira, Thomas D. Bullen and Ellen Thomas. Science (December 12, 2008)

Source: Carnegie Institution

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Dec 11, 2008
Blah Blah Blah, Climate change, give me money. State a few common sense facts, attribute it to climate change, blame the change on people and collect money.

What did they do that's worth money?

First person to say make awareness needs to be hit. We all know what you think. If I wanted to hear problems I'd hang out at the homeless shelter. If no one can think of a real solution it's irrelevant whether I agree with the BS that's piled up or not. OK, CO2 is killing everything I agree, now name 1 real solution, something everyone is willing to accept, no cars is not acceptable, no heat, lights, hospitals? I can't find enough unicorns to fart to drive my windmill. That being said, if the Earth has done this before it can probably survive this again, and was probably already headed that direction.

The hot button of the day seems to be acidification of the oceans. can someone point me to some factual numbers not skewed by overfishing, wastewater pollution, trashdumping, or other source of more probable contamination? Seriously, if I run over a pedestrian and he dies and I blame it on AGW then please lock me in jail, but your giving hundreds of polluters an easy out. It's not my trash/wastewater/overfishing/killing off of sealife that is causing this, everyone else is causing it by driving their cars 10,000 miles away from here. I'm waiting for someone to blame Darfur on AGW.

Dec 11, 2008
Roach, your attitude is all wrong. Linking ones research to the problem of the day is common practice in all areas of science. You'd realise that if you were a scientist.

Dec 11, 2008
It was natural 13 million years ago and it would be natural if it happens now, so what's the buzz?

Dec 11, 2008
Roach: You are a real defeatist if you think that we can't work our way out of this problem.

If you don't think there is a problem, go look at the plot of measured CO2 in the atmosphere over the past 30 years.

If you still don't think we have a problem then you don't understand radiative heat transfer and it just doesn't matter what anyone thinks, you will just continue your ranting no matter what evidence is in front of you.

For those of you who don't understand why a change of a few ppm of CO2 can make a difference, I will go over it. The major greenhouse gas that keeps us from being a frozen ball of ice is water vapor. Water vapor has raised the temperature of the earth, most of the way, from the a temperature below zero to that which we live in. However, water vapor absorbs lines/bands of the spectrum and there is room between some of those lines/bands. It just happens that CO2 absorbs in some of the vacant bands in the water vapor spectrum. So, it fills in the areas of the near/mid infrared where water vapor does not. There is plenty of room in those bands for CO2 to increase the absorption since it is at ppm levels. That was predicted more than 100 years ago and has proven to be correct. We can watch the CO2 in the atmosphere go up and anyone with a first course in radiative heat transfer can calculate the effect. That is not a matter of conjecture, it is heat transfer. What is a matter of conjecture is how the increase in temperature that we are causing by burning fossil fuels is going to affect the weather and climate. That issue is still an evolving area of scientific research.

Dec 11, 2008
Climate Change Alters Ocean Chemistry..

How do you know that the oceans chemistry isnt driving climate change??

"If you don't think there is a problem, go look at the plot of measured CO2 in the atmosphere over the past 30 years. "

Ahhh, CO2 lags temperature.......

Dec 12, 2008
Mr. Thermodynamics, Once you leave your junior level heat transfer class where you can perfectly calculate everything, you generally go to a senior level systems class where they tell you that your heat transfer class is practically worthless. While heat transfer theory can give you an idea about what will happen, it cannot do so with any accuracy in a real system. Even something so (relatively) simple as a fluidized bed reactor is completely unmodelable due to the complexities. Small changes can change everything (my catalyst professor loved this story where the night janitor improved the reactor efficiency by 5% by urinating in the reactor). The problem is that we aren't increasing CO2 in isolation. We are increasing and decreasing every variable by varying amounts. While we know that in isolated air of current composition, doubling CO2 leads to a ~0.6C increase in temperature. However, we are unsure even of the direction of the multiplier. The IPCC's number is little better than a random guess as the major player are clouds, which can both warm and cool in various circumstances.

In short, the problem is one of magnitude. To use your heat transfer class, one item is significantly hotter than the other. This is like high school physics where you can ignore air resistance on falling objects. This leads to the relative error being small. However, in miniscule changes to systems, the error is the same but the change is very small. That's the problem with current climate change models and and numbers, the error is larger than the change. The error bars go both positive and negative at a margin so wide that the tiny changes in the average become rapidly meaningless. Now, if you think that 1.5C /-20C of warming (sorry for the lack of reference, I can't remember where I found this) makes a decent case for massive interventions, then you need to go back to freshman statistics.

Dec 12, 2008
How do you know that the oceans chemistry isnt driving climate change?

How do we know that your preconceived conclusion(s) isn't(aren't) determining your premise(s)?

Dec 13, 2008
BenD said "Mr. Thermodynamics, Once you leave your junior level heat transfer class where you can perfectly calculate everything, you generally go to a senior level systems class where they tell you that your heat transfer class is practically worthless. While heat transfer theory can give you an idea about what will happen, it cannot do so with any accuracy in a real system."

Ben: You have missed the point. I am not in disagreement that real systems get messy. That is why I limited my writing to a simple radiative example. The example should make it clear why the addition of CO2 to the existing atmospheric mix raises the temperature of the globe. The ugly part comes in when you try to predict the local effects of the overall change. You have all four phases of matter interacting including plasma in the upper atmosphere, gases in the atmosphere, liquid in the oceans and solids on land. I didn't even try to address that distribution of extra energy because it takes books, thousands of research projects, and millions of lines of computer code. It is the simple trapping mechanism I described. It is the interaction of the excess energy I described above that is the tough part that requires a lot of work.

The point is that people are working on it and giving it an honest effort. The idea of ridiculing a model that is not good at certain aspects of global weather modeling is not looking at the bigger picture of that being the way we make better estimates.

Yes, the example was simple. However, it is one of the issues that no one is saying is incorrect because it is so simple and basic. Just think about it. Increasing CO2 traps more IR. More trapped IR means the Earth heats up (with all of the other signals imposed on the monotonic heating).

So, if you want to use the information from the second course in radiant heat transfer you will have to start building your computer models. If you just want to understand why the earth can be heated by a small increase in CO2 you can do it with a spreadsheet.

I hope you understand the difference between CO2 radiation trapping (a first course mechanism) and the changes in weather/climate (which is not even touched until you are working on a thesis).

Dec 13, 2008
Right, CO2 is growing at an astounding rate!!!

Dec 14, 2008
So Let me get this right, Because I want to see people present solutions not waste my money on pointless research I'm the defeatist? Are you people so stupid as to honestly believe that you can study your problems away?

It doesn't matter whether we can fix the problem or not or even if there is one, which by the way thermo, we need to see this CO2 meter you've been using for the past 30 years, because I'm guessing a 30 year old meter has a larger margin of error than the one that plugs into my Fluke Meter. The fact that everone who is so worked up about AGW also doesn't want to see any solutions tells me how much you belive in it.

Jan 29, 2009
Glad you're still reading, Roach, 'cause here's a solution for you: Use the same economic incentives that subsidized the release of the CO2 up to now, to close the resource loop. More explicitly: Enforce an auction/market in Carbon Credits where the "grandfathered in" allocation diminishes to zero. And then only count Credits that actually involve sequestering Carbon out of the biosphere, not just reducing emissions. The free market would fund a sequestration industry with all the alacrity for which it is rightly esteemed and the problem would be removed, with any kind of unmitigated coal-fired plant going the way of buggy-whip factories of yore.

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