Mysteriously warm times in Antarctica

Mysteriously warm times in Antarctica
Dr Robert Mulvaney cuts an ice core in the cold room at the British Antarctic Survey headquarters, Cambridge

(PhysOrg.com) -- A new study of Antarctica's past climate reveals that temperatures during the warm periods between ice ages (interglacials) may have been higher than previously thought. The latest analysis of ice core records suggests that Antarctic temperatures may have been up to 6°C warmer than the present day.

The findings, reported this week by scientists from the British Antarctic Survey (BAS), the Open University and University of Bristol in the journal Nature could help us understand more about rapid Antarctic climate changes.

Previous analysis of ice cores has shown that the climate consists of ice ages and warmer interglacial periods roughly every 100,000 years. This new investigation shows temperature 'spikes' within some of the interglacial periods over the last 340,000 years. This suggests Antarctic temperature shows a high level of sensitivity to greenhouse gases at levels similar to those found today.

Lead author Louise Sime of British Antarctic Survey said,

"We didn't expect to see such warm temperatures, and we don't yet know in detail what caused them. But they indicate that Antarctica's climate may have undergone rapid shifts during past periods of high CO2."

During the last warm period, about 125,000 years ago, sea level was around 5 metres higher than today.

scientist Eric Wolff of British Antarctic Survey is a world-leading expert on past climate. He said,

"If we can pin down how much warmer temperatures were in Antarctica and Greenland at this time, then we can test predictions of how melting of the large ice sheets may contribute to ."

More information: Evidence for warmer interglacials in East cores by Louise C. Sime, Eric W. Wolff, Kevin I. C. Oliver and Julia C. Tindall is published online this week in the journal Nature.

Provided by British Antarctic Survey (news : web)


Explore further

Old ice provides insights into major climate change

Citation: Mysteriously warm times in Antarctica (2009, November 18) retrieved 19 October 2019 from https://phys.org/news/2009-11-mysteriously-antarctica.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
0 shares

Feedback to editors

User comments

LKD
Nov 18, 2009
"Previous analysis of ice cores has shown that the climate consists of ice ages and warmer interglacial periods roughly every 100,000 years. ... During the last warm period, about 125,000 years ago, sea level was around 5 metres higher than today."

So we are 25,000 years late and this warming is completely natural and expected, and due to go up 6 more degrees. Where are the AGW experts to refute this article?

Nov 18, 2009
What sound does a house of cards make when it crumbles? *fwoosh* *pitter-patter* *clik-a-tat-ik-a-towi*?

Anyway, imagine that sound, because ANTHROPOGENIC Global Warming is bunk and the truth is arriving daily now it seems.

P.S. you still may want to sell your coastal property ;)

Nov 18, 2009
This comment has been removed by a moderator.

Nov 18, 2009
"We didn't expect to see such warm temperatures, and we don't yet know in detail what caused them. But they indicate that Antarctica's climate may have undergone rapid shifts during past periods of high CO2."

This obfuscation looks to me like an attempt to say nothing negative about a failed paradigm (CO2 based global warming) shot through and through with so many holes it can no longer float. It has been shown in study after study that past elevated CO2 levels FOLLOW warmings as the seas de-gas, never lead them. I have every confidence that closer analysis of the data recoverable from these cores will show exactly the same thing.


Nov 18, 2009
LKD - We are not 25k years 'late' for anything. Around 100k years is a very general statistical estimate and varies considerably. The chances of this having something to do with whats been happeing in the last 30-40 years is basically 0.

I have not seen any studies that show that CO2 levels follow warming. I certainly do agree that just because CO2 levels rise during warming periods doesn't mean that one causes the other.

On the other hand, greenhouse warming effects are pretty simple physics. Its really unlikely that high CO2 levels would not magnify any warming trend that was based on other causes considerably.

Why is it that people just cannot believe that human civilization could affect the world in this way? The rise in CO2 levels is easily measurable and real.

Nov 18, 2009
@Parsec If you look at the CO2 absorption bands in the IR they are about 95% saturated at ca. 300 ppm of CO2. In other words, 95% of the IR energy is already absorbed. That is why the Earth is nice and cozy. However, doubling the concentration from say 300 ppm to 600 ppm will only increase the overall absorption of the IR energy by a portion of the 5% remaining. That additional absorption is not enough to amount to a hill of beans and therefore CANNOT contribute more than a few percent to the overall observed global warming. Something else is driving the change and that is likely the suns output (search; Langscheit and solar cycles).

There are some excellent papers out there that show how warming precedes CO2 elevation. (Sorry I can't reference them for you. I lost them when I had to rebuild my computer recently.)

Nov 18, 2009
Might be the fact that we have less trees?

LKD
Nov 18, 2009
Parsec- No, not terribly late, an exaggeration I am sorry. But still, it is awfully coincidental. And it has not been happening for 30 years, more along the lines of 150 years, if not more, depending when the height of the little ice age was.

Does human kind effect the planet? On a small scale sure, on a large scale, that is impossible without nuclear Holocaust. We do too many contradictory things. If anything, the planet should be cooler as pollution, evidenced by volcanoes, shields the planet from the sun and blocks light, instead the opposite is happening.

The problem with crediting CO2 is that it is only 0.0383% of the earth's atmosphere. And also it hearkens back to the 70's global cooling idiocy.

So far, I don't think a single prediction has come true from the AGW side. New York is still above sea level. There are less hurricanes. The list goes on.

I believe that this has more to do with out movement in the Milky Way and solar flares, then it does with the amount of CO2.

LKD
Nov 18, 2009
Parsec- By the way, thank you for being sincere and honest with your responses. I hope mine are as well. Though likely I failed there. My apologies.

Nov 19, 2009
So. It will be just that much warmer in our near future and the oceans will be that much higher. Got waders?
Oh, and the increase in temperature/ocean levels will come that much faster too.
All due to the addition of carbon caused temperature rise in addition to that 'normal' increase.
What me worry? Nope. I live at 6000 feet asl.

LKD
Nov 19, 2009
DMCL-

Thank you. I just wish we could ALL have a discussion about this. I won't mind being wrong, but I can't handle when the insane stand up and proclaim that the global warming will get so bad, we will turn to cannibalism. (http://www.wnd.co...d=60581)

Nov 19, 2009
This comment has been removed by a moderator.

LKD
Nov 19, 2009
Dan Halen-
A 1% change would be astronomical, and is not physically possible! May I remind you there is not even 1/2 of 1/2 of 1% of Carbon-dioxide in the air. You can't make CO2 multiply itself 33 times to get your fictitious 1% change to justify the policy you wish to inflict on people.

Nov 19, 2009
LKD: Please view: http://www.youtub...j8sUybx0
Slides available at: Vhttp://mnfreemark...ntation/
with the video.

View this before you make a decision to join the "fools forum" of Climate Change.

Nov 19, 2009
One thing to watch out for.... Media covers the dramatic and exaggerates it for profit; then politicians and investors try to exploit it.

Second piece of reality.... the history of science is heavily ladened with evidence that "majority opinion" among "the experts" is NOT proof, and in fact is often proven wrong in the long run.

Third bit of reality.... Human nature is to inflate our own significance: a) to think that we are capable of causing huge changes; b) to think that a few feet of sea rise, ruining OUR beach front property, is consequential to Mother Nature.

The antidote to these flaws in humanity is a bit of humility, maturity, adaptability and a few grains of common sense. When applied, the AGW fears usually shrink in size to something we can talk about but not waste time and money on blindly.

Nov 19, 2009
One of the "debacles" of this decade is the discovery that our government and all the economic scientists... in spite of working with completely man made systems, functioning based upon business math (...no irrational numbers or singularities here!) was taken by surprise by last year's market crash. ...unleashing massive destruction downstream.

We deceived ourselves about something we had near total control over and complete visibility into.

And yet we have the timidity to think we understand what we're doing to the environment?

Nov 19, 2009
LKD, so a 1% change in the radiative transfer of heat is impossible? care to back that up with something more than rhetoric? I doubt it. Here's what's really going on and why the "saturation" argument is bullshit.

"What happens if we add more carbon dioxide? In the layers so high and thin that much of the heat radiation from lower down slips through, adding more greenhouse gas means the layer will absorb more of the rays. So the place from which most of the heat energy finally leaves the Earth will shift to higher layers. Those are colder layers, so they do not radiate heat as well. The planet as a whole is now taking in more energy than it radiates (which is in fact our current situation)."

http://www.aip.or...m#L_0141

Nov 19, 2009
This comment has been removed by a moderator.

LKD
Nov 20, 2009
Dan Halen-

You stated:

"Adding more greenhouse gas there will change the balance. Moreover, even a 1% change in that delicate balance would make a serious difference in the planet’s surface temperature."

That clearly refers to percentages of actual gas. Not IR absorption. Feel free to correct your statements.

Nov 20, 2009
there are several predictions that appear to be accurate to some degree

The whole point of this article is that the variations we see and that AGW proponents predict are completely within natural variability. This means anthropogenic CO2 has NOTHING to do with what is happening with the global temp. This study completely disarms AGW. Sell your coastal property, yes, but don't blame it on man or believe we can change where the global climate is going.
The planet as a whole is now taking in more energy than it radiates (which is in fact our current situation).

This demonstrates nicely how you have absolutely no understanding of the science. You can now stop posting like you know what you're talking about. Thank you.

Our planet has never had a negative net irradiance. If it did there would be no life on earth. Maybe you're not aware of this, but it is the sun and green house gases which make life on earth possible. Really, did you even think about what you typed there?

Nov 20, 2009
Dan Halen-

You stated:

"Adding more greenhouse gas there will change the balance. Moreover, even a 1% change in that delicate balance would make a serious difference in the planet�s surface temperature."

That clearly refers to percentages of actual gas. Not IR absorption. Feel free to correct your statements.


Read it again in context dumbass. The paragraph immediately above what you quoted makes clear the 1% is absorbance, not CO2.

Nov 20, 2009
The whole point of this article is that the variations we see and that AGW proponents predict are completely within natural variability.


No that is not the point. Just because natural forces in the distant past warmed Antartica does NOT mean that they are the most parsimonious explanation of the current warming.

Our planet has never had a negative net irradiance. If it did there would be no life on earth. Maybe you're not aware of this, but it is the sun and green house gases which make life on earth possible. Really, did you even think about what you typed there?


This is laughably stupid. Of course the net irradiance has been negative (and positive) in the past. If it hadn't, we would never have had ice ages or warm periods*. You don't have a clue what you're talking about. Just another scientific illiterate trying to sound erudite. Now go home and jerk off to the Glen Beck show.

Quiz question: When a chunk of ice is melted by the sun what is its net irradi

Nov 21, 2009
Certainly when ice has melted to water it no longer factors, but while it adds to height it also adds somewhat to width too.
Hence the sea moving inland and cutting roads.
However, the sea also reflects as well as being a heatsink, and unless you have some really impressive math to explain the rate of change and likely result of this you are just speculating and will have to wait and see like the rest of us.
It's still better to act defensibly now even if we are wrong than to sit back and do nothing.


No impressive math is needed. Imagine a cold planet, now imagine a warm one. The cold planet is at a low energy state, the warm one at a higher energy state. How do you get from cold planet to warm? You add energy. Where does that energy come from? It comes from radiating less energy into space than you absorb, hence a net negative irradiance for a time. Thus, defuncdeity is a defunctmoron. QED.

Nov 21, 2009
Just because natural forces in the distant past warmed Antartica does NOT mean that they are the most parsimonious explanation of the current warming.

Actually it does. Do you read your own posts? Do you realize how desperate you sound?
Of course the net irradiance has been negative...

Boy did you get defensive, quite characteristic of one who's been publicly embarrassed. Not that we needed your childish responses to know you have no clue what you're saying.

Again, so sorry friend, this isn't debatable, I suggest you read a book, though the wiki may be more your speed. Just because there's ice ages doesn't mean the globe has negative net irradiance. There are negative fluctuations, sure, but water has a high freezing point in degrees Kelvin, we ALWAYS have positive irradiance. You may apologize.

Again, stop pretending like you have any idea what you're talking about, it will only make you look more foolish, if that's possible. Which at this point, it probably isn't.

Nov 22, 2009
"The greenhouse effect will in fact operate even if the absorption of radiation were totally saturated in the lower atmosphere. The planet's temperature is regulated by the thin upper layers where radiation does escape easily into space. Adding more greenhouse gas there will change the balance. Moreover, even a 1% change in that delicate balance would make a serious difference in the planet’s surface temperature."

Stop using 19th century science

Nov 22, 2009
"The greenhouse effect will in fact operate even if the absorption of radiation were totally saturated in the lower atmosphere. The planet's temperature is regulated by the thin upper layers where radiation does escape easily into space. Adding more greenhouse gas there will change the balance. Moreover, even a 1% change in that delicate balance would make a serious difference in the planet’s surface temperature. The logic is rather simple once it is grasped, but it takes a new way of looking at the atmosphere — not as a single slab, like the gas in Koch's tube (or the glass over a greenhouse), but as a set of interacting layers. (The full explanation is in the essay on Simple Models, use link at right.)"
www.aip.org/histo.../co2.htm

Hope this post works

Nov 22, 2009
I think CO2 clouds the whole warming theme. CO2 levels are up by 30%, CH4 by 150%, N2O by 15% over the past three centuries. Bearing in mind CH4's greater propensity for warming, should we be more concerned about CH4? I have no training or background speciality in this, but took figures from IPCC.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more