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  (Source: Travelvivi)
But scientists say it did not contribute to global warming today

Lawrence Livermore National Laboratory (LLNL) scientist, along with his team, recently used radiocarbon dating to trace carbon dioxide released to the atmosphere from the deep ocean at the end of the last ice age.

Radiocarbon dating employs the use of radioisotope carbon-14 to figure out the age of ancient and prehistoric carbonaceous materials. This process can be used on materials as old as 62,000 years old. 

Tom Guilderson, a scientist at the LLNL's Center for Accelerator Mass Spectrometry and an author of the study, found that an increase in atmospheric CO2 concentrations corresponded with a decreased amount of carbon-14 relative to carbon-12 in the atmosphere. 

"This suggests that there was a release of very 'old' or low 14/12CO2 from the deep ocean to the atmosphere during the end of the last ice age," said Guilderson. He noted that CO2 release may increase the rate at which ice melts after an ice age. 

Ocean circulation regulates radiocarbon in the atmosphere, and in turn, this regulates the sequestration of carbon dioxide in the deep ocean by atmosphere-ocean carbon exchange. Around 110,000 to 10,000 years ago when the last ice age occurred, lower atmospheric carbon dioxide levels coincided with increased atmospheric radiocarbon concentrations, which have been "credited to great storage of CO2 in a poorly ventilated abyssal ocean." The circulation of the ocean was drastically different back then, and Guilderson admits that he and his team do not fully understand the manner in which carbon was stored in deep ocean at that time. 

The team dated two sediment cores from the subtropic South Pacific near New Zealand and the sub-Antarctic to be approximately 13,000 and 19,000 years old. Guilderson was able to determine when the large CO2 release occurred using the carbon-14 in the cores. Also, he was able to determine the ocean pathway by which it escaped. 

"In this case, the absence of a signal is telling us something important," said Guilderson. "Deeper waters substantially depleted in carbon-14 were drawn to the upper layers and this is the main source of the CO2 during deglaciation. Data suggests that the upwelling of this water occurred in the Southern Ocean, near Antarctica. In our cores off New Zealand, which lie in the path of waters which 'turn over' in the Southern Ocean, we don't find anomalously low carbon-14/12 ratios.

"This implies that either water which upwelled in the Southern Ocean, after 16,500 years ago, had a vigorous exchange with the atmosphere, allowing its 14C-clock to be reset, or the circulation was significantly different than what the current paradigm is. If the paradigm is wrong, then during the glacial and deglaciation, the North Pacific is much more important than we give it credit for."

This carbon dioxide release sped up the melting, but when asked about CO2's contribution to

global warming today, Guilderson said this release of CO2 from the last ice age "is not relevant." But he did mention that he has used radiocarbon dating on CO2 in the atmosphere today, and that isotopic signature shows that use of fossil fuels is what is causing global warming. 

The study was published in the August 26 edition of Nature



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RE: Slow news day
By mdogs444 on 8/30/2010 3:32:14 PM , Rating: 2
You really need to read up on the subject if you have this many questions. I'll give you a hint - it was started by the United Nations in 1988 with the nudge from a European politician who publicly stated that we needed a way to make the UN the new global government of all countries.


RE: Slow news day
By PaterPelligrino on 8/31/2010 1:12:06 AM , Rating: 2
And this is what passes for intelligent dialogue in the United States: two camps convinced that the other side is stupid and evil.

The left thinks conservatives are all small-town, know-nothing racists, who barely made it out of high school, have never been more than 20 miles from where they were born, and haven't a thought in their heads that wasn't put there by Fox News. For a conservative, if it wasn't invented in America and isn't written in English, it can't be trusted. Liberals see simple-minded, mean-spirited dupes who have been completely hoodwinked by the rich into supporting policies that benefit only the rich. It sees Glenn Beck and Sarah Palin as just another iteration of Jim Bakker and Tammy Faye. It sees a crowd of mindless and scared sheep just one rabble rouser away from picking up their torches and marching off to burn the heathens and the commies to the ground. Most of all, it sees people too dumb to know what's good for them. Liberals think that if a conservative would just read the right books and watch The Daily Show he'd come round to the liberal point of view.

The right thinks liberals are all closet-commies who want to destroy capitalism and give away all our wealth to the undeserving poor. It sees people who hate god and hate America. It sees people who want government to control everything. Conservatives think liberals don't want to have to work for a living, that they want to sit around all day in coffee shops sipping espresso, reading the New York Times, and telling each other how much better life would be if they only lived in Paris. They see a vast conspiracy of European socialists - Jews, yes we know they're all Jews, or even worse French! - who created the World Bank and the UN to subvert freedom-loving, god-fearing Americans who just want to be left alone and make their way in this world by the honest sweat of their brows. It thinks all problems are created by government, that if the environmentalists and tax-and-spenders would just stop harassing people, all of life's problems would go away. It thinks America is being dragged down the wrong path by liberal do-gooders.

Most people really do look at the world as a Dr Strangelove battle between good and evil. How is this any different than a place like Pakistan where everything that goes wrong in life is automatically assumed to be the result of a CIA conspiracy? Life isn't a battle between good and evil, it's a struggle between competing views of the good.


RE: Slow news day
By Ammohunt on 9/1/2010 2:44:20 PM , Rating: 2
Hardly, its about those that are hyper informed and those that are not. Most people judge others by their actions and can easily distill motivations from an established pattern of said actions. Its much easier to figure out what Leftists are about since after they are confortable enough to feel they will come out on top openely discuss their motivations and brag about it every chance they get. Its not rocket science its simple observation coupled with a basic yet accute understanding of human nature.


RE: Slow news day
By PaterPelligrino on 9/2/2010 12:22:08 PM , Rating: 2
Let me see if I follow you here.

You're saying that conservatives like yourself, who claim that AGW was thought up by the left "to ban Capitalism outright in Rich Western countries", are "hyper-informed", while your liberal opponents don't share your grasp of the issues.

Then in the 2nd sentence you state that because liberals are confident of the correctness of their position, and certain that they'll prevail in the end, they openly admit what they're after, and therefore it's easy to figure out what they want - which is, as you previously stated, the "outright banning of capitalism in the rich West".

Have I got that right?

Odd, though, that I've never heard an AGW proponent admit to wanting to ban capitalism in the West, let alone brag about it, but let's not quibble about details.

All in all, a very convincing argument you have there. I feel I should apologize. I clearly did you a disservice when I lumped you in with all those other conservatives who distort and misrepresent your opponents' positions.

It's not often that one encounters a guy with such an "acute understanding of human nature". Hats off to you bro.


RE: Slow news day
By Ammohunt on 9/2/2010 2:16:44 PM , Rating: 2
Reading comprehension not one of your strong points I see. Sorry i don’t have the patience to day to dumb it all down for you rest assured it will all come clear to you eventually.


RE: Slow news day
By PaterPelligrino on 9/2/2010 3:41:17 PM , Rating: 2
quote:
rest assured it will all come clear to you eventually.


I wouldn't count on it Ammohunt; after all, not everyone possesses your "hyper-informed" knowledge of the issues, and "acute understanding of human nature".


"It's okay. The scenarios aren't that clear. But it's good looking. [Steve Jobs] does good design, and [the iPad] is absolutely a good example of that." -- Bill Gates on the Apple iPad














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