Through the Looking Glass: Scientists Peer Into Antarctica's Past to See Our Future Climate

Apr 29, 2010 by Will Ramos
Physical Properties Specialist Travis Hayden of Western Michigan University takes measurements from a core section in one of the labs onboard the JOIDES Resolution. Credit: John Beck, IODP/TAMU

In response to growing concerns about our planet’s changing climate, rising global temperatures and sea levels, and increasing concentrations of atmospheric carbon dioxide (CO2), scientists are looking to the planet’s past to help predict its future. New results from a research expedition in Antarctic waters may provide critical clues to understanding one of the most dramatic periods of climatic change in Earth's history - and a glimpse into what might lie far ahead in our climate’s future.

The poles control much of our global climate. Giant ice sheets in Antarctica behave like mirrors, reflecting the sun's energy and moderating the world's temperatures. The waxing and waning of these ice sheets contribute to changes in sea level and affect , which regulates our climate by transporting heat around the planet.

Despite their present-day , the poles were not always covered with ice. New climate records recovered from Antarctica during the recent Integrated Ocean Drilling Program (IODP) "Wilkes Land Glacial History" Expedition show that approximately 53 million years ago, Antarctica was a warm, sub-tropical environment. During this same period, known as the "greenhouse" or "hothouse" world, atmospheric CO2 levels exceeded those of today by ten times.

Then suddenly, Antarctica's lush environment transitioned into its modern icy realm. In only 400,000 years - a mere blink of an eye in geologic time - concentrations of decreased. dropped. Ice sheets developed. Antarctica became ice-bound.

How did this change happen so abruptly and how stable can we expect ice sheets to be in the future?

The JOIDES Resolution passed icebergs such as this one during its recent expedition to Wilkes Land, Antarctica. Credit: Rob Dunbar & IODP

To answer these questions, an international team of scientists participating in the Wilkes Land Glacial History Expedition spent two months aboard the scientific research vessel JOIDES Resolution in early 2010, drilling geological samples from the seafloor near the coast of Antarctica. Despite negotiating icebergs, near gale-force winds, snow, and fog, they managed to recover approximately 2,000 meters (over one mile) of sediment core.

"These sediments are essential to our research because they preserve the history of the Antarctic ice sheet," observed Dr. Carlota Escutia of the Research Council of Spain CSIC-University of Granada, who led the expedition, along with co-chief scientist Dr. Henk Brinkhuis of Utrecht University in the Netherlands. "We can read these sediments like a history book," Brinkhuis explained. "And this book goes back 53 million years, giving us an unprecedented record of how ice sheets form and interact with changes in the climate and the ocean."

Wilkes Land is the region of Antarctica that lies due south of Australia, and is believed to be one of the more climate-sensitive regions of the polar continent. The new core samples collected during IODP's Wilkes Land expedition are unique because they provide the world's first direct record of waxing and waning of ice in this region of Antarctica.

Combined, the cores tell the story of Antarctica's transition from an ice-free, warm, greenhouse world to an ice-covered, cold, dry "icehouse" world. Sediments and microfossils preserved within the cores document the onset of cooling and the development of the first Antarctic glaciers and the growth and recession of Antarctica's ice sheets. Cores from one site resemble tree rings - unprecedented alternating bands of light and dark sediment preserve seasonal variability of the last deglaciation that began some 10,000 years ago.

With cold hands, paleomagnetist Saiko Sugisaki of the Graduate University of Advanced Study in Japan prepares a core for sampling. Credit: John Beck, IODP/TAMU

Understanding the behavior of Antarctica's ice sheets plays a fundamental role in our ability to build robust, effective global climate models, which are used to predict future climate. "These models rely on constraints imposed by data from the field," the co-chiefs pointed out. "Measurements of parameters such as age, temperature, and carbon dioxide concentration provide invaluable inputs that help increase the accuracy of these models. The more we can constrain the models, the better they'll perform - and the better we can predict ice sheet behavior."

What's next? The science team now embarks on a multi-year process of on-shore analyses to further investigate the Wilkes Land cores. Age-dating and chemistry studies among other analyses are expected to resolve changes in Antarctica's climate over unprecedented short timescales (50-20,000 years). Data collected from the Wilkes Land expedition will complement previous research from drilling operations conducted elsewhere in the Antarctic over the last 40 years. Together, this research will provide important age constraints for models of Antarctic ice sheet development and evolution, thereby forming the basis for models of future behavior and polar climatic change.

Explore further: NASA sees last vestiges of Tropical Depression Jack

Provided by Integrated Ocean Drilling Program Management International

4.2 /5 (5 votes)

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User comments : 8

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LuckyBrandon
1 / 5 (5) Apr 29, 2010
How cna you get information about the climate from ice that is supposedly from a period when there was no ice? Thats like catching a fly on fly paper even though the fly was never there...
JayK
4 / 5 (4) Apr 29, 2010
Sediment cores. Not ice, sediment.
jcrow
2.7 / 5 (3) Apr 29, 2010
Here come the trolls. Its funny how some people are programmed to respond to anything about the climate like its some kind of lie.
CWFlink
not rated yet Apr 30, 2010
So this may answer a question I've asked in a couple of other forums about the impact of a major volcano in the vacinity of an oil field.... possible scenario:

1) earthquake spawns volcano in/near ancient oil and/or coal field;
2) huge quantities of CO/CO2, methane and particulate carbon (smoke) released into atmosphere;
3) blocked sunlight kills vegitation and cooling surface leading to ice age;
4) CO2 levels rise to over 10 times greater than now, augmented with methane due to rotting vegitation;
5) hot-house effect defrosts antartica, turning it into a garden paradise ... and lifeboat for the planet.

Is this what this (and other) research is saying?

Can someone put the pieces together and see if the time-line works?

If so, it would substantiate the theory behind global warming, but undermine the hype that this has never happened before and would lead to the end of life on this planet.

Some science "facts" plese... we have had enough political hype from both sides.
Skeptic_Heretic
not rated yet Apr 30, 2010
So this may answer a question I've asked in a couple of other forums about the impact of a major volcano in the vacinity of an oil field.... possible scenario:

Not really geologically possible.

In order to develop an oil field you need an area of intense pressure at a level heat for an extended period of time in order to convert from kerogen to petroleum. Most theories state that volcanism would disrupt this process and instead oxidize the kerogen into asphaltines, resulting in tar volcano or asphalt domes as we've recently discovered off the coast of California.

Now assuming that an oil field could come in contact with active volcanism, ie plate shift, etc, the oil would be burned up and produce the same gases we already note in emission from volcanos. CO2, H2O, CH4, CF6, etc.

As to your paradise statements, we can't really state that would be the case as the wind and ocean currents have greatly changed from 53mil years ago.
JayK
1.5 / 5 (2) Apr 30, 2010
If so, it would substantiate the theory behind global warming, but undermine the hype that this has never happened before and would lead to the end of life on this planet.

Extinction events are sort of unpleasant for the larger life forms during any age. You know, that whole death of humankind thing that really ruins your day?
LuckyBrandon
3 / 5 (2) Apr 30, 2010
jayK-ah yes, I was for some reason thinking is said ice cores, but you are indeed correct, it says sediment cores. thank you for the correction there, and that makes much more sense :)

jcrow, and whoever voted him the 5-your an idiot, assuming you were pointing that at me. It's funnier that people would make a retarded statement like that. For the record, I think climate change is real, but isn't man made to the extent that its spouted off all the time. I happened to misread, and you happened to make an assumption.
JayK
1.5 / 5 (2) Apr 30, 2010
Given the amount of concern trolling that has been on this site lately, I can understand jcrow's reaction. If I hadn't known your history, LuckyBrandon, I would have probably assumed the same about your comment.

Of course, jcrow could also be preparatory for the eventual entrance of the professional denialism of dachypolypass and his kind.

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