Image copyrightJANE FRANCIS/BASImage captionA message from the Pliocene: A warmer world that saw plants persist in the Antarctic interior
Scramble across exposed rocks in the middle of Antarctica and it's possible to find the mummified twigs of shrubs that grew on the continent some three to five million years ago.
This plant material isn't much to look at, but scientists say it should serve as a warning to the world about where climate change could take us if carbon emissions go unchecked.
The time period is an epoch geologists call the Pliocene, 2.6-5.3 million years ago.
It was marked by temperatures that were significantly warmer than today, perhaps by 2-3 degrees globally.
These were conditions that permitted plant growth even in the middle of the White Continent. Higher, too, were sea-levels. It's uncertain by how much, but possibly in the region of 10-20m above the modern ocean surface.
What's really significant, though, is that the amount of carbon dioxide in the atmosphere was very similar to what it is today - at around 400 CO2 molecules for every million molecules of air.
Indeed, the Pliocene was the last time in Earth history that the air carried this same concentration of the greenhouse gas.
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And it tells you where we're heading if we don't get serious about addressing the climate problem, cautions Prof Martin Siegert from the Grantham Institute at Imperial College London.
Media captionProf Jane Francis: "The polar regions are the regions on Earth most sensitive to change"
Temperatures may currently be lower than in the Pliocene, but that's only because there is a lag in the system, he says.
"If you put your oven on at home and set it to 200C, the temperature doesn't get to that level immediately; it takes a bit of time," he told reporters.
"And it's the same with Earth's climate. If you ratchet up the level of CO2 at 400 parts per million (ppm), it won't suddenly get to an equilibrium overnight. It will take maybe 300 years or something.
"So, the question to us is: what is the equilibrium state; what is Earth's climate going to look like with 400ppm, all things being settled?"
These experts want to see much more research into the parallels between then and now.
Image copyrightT.RONGE/AWIImage captionProf van De Flierdt (left): Much of what we know currently comes from ocean sediments
A lot of the knowledge we have presently about the epoch comes from ocean sediments.
These muds, drilled off the coast of Antarctica, contain fossil organisms whose geochemistry can be used to reconstruct ancient temperatures and the corresponding likely volume of ice on the planet.
If, as the scientists suspect, sea-levels were 10-20m higher in the Pliocene, it indicates the ice sheets must also have looked very different.
"The Greenland Ice Sheet holds about 7m (equivalent of sea-level rise). That was probably gone," said Imperial's Prof Tina van De Flierdt.
"In Antarctica, we have the smaller West Antarctic Ice Sheet which holds about 5m. That was probably gone, too.
"And then we have the big chunk in East Antarctica. There are certain parts of that which people have believed to be stable for a very long time. But that kind of doesn't work with the numbers. If we need more than 10m of sea level rise, we need East Antarctica to be unstable as well."
This could certainly explain the presence of plants in the middle of a continent where today only lichens and mosses can survive.
Image copyrightJANE FRANCIS/BASImage captionThese rocks, which hold fossil plants from the Pliocene, are just 500km from the South Pole
Prof Jane Francis, the director of the British Antarctic Survey, pulled her fossilised shrub material from rocks just 500km from the South Pole.
"These are twigs similar to southern beech," she told BBC News. "I like to call them the remnants of the last forests of Antarctica.
"They're probably Pliocene in age. What we're looking at is a time when the glaciers retreated and we were left with areas in front of those glaciers where tiny little shrubs could grow. It wouldn't have been a nice place to live; it would have been a tundra kind of environment, but with enough sunshine in summer and temperatures (able to rise) up to about 5C."
A key unknown is how much, how soon. How fast could Antarctica retreat in the modern era if the global climate responds to the warming forced by 400ppm?
Image copyrightEMPICSImage captionIt's not clear how fast the glaciers of Antarctica can respond to the warming in-built in 400ppm
Conceivably very fast, is the answer from Prof Rob DeConto from the University of Massachusetts-Amherst.
He runs computer models which incorporate physical processes in the ice that can result in the rapid collapse of cliffs at the front of Antarctic glaciers terminating in the ocean.
"Today we are measuring sea-level rise in millimetres per year. So, a little more than 3mm per year right now," he explained.
"But these new processes imply the potential for centimetres per year. But we're looking to the geologists for guidance about rates. Maybe, it takes 10,000 years to get to 20m. We've still got a lot more work to do."
For Prof Siegert, the imperative is to bring carbon emissions under control very quickly and then reverse the concentration.
"Can we restrict temperature rise to 1.5 degrees this century? Can we do that? It's possible," he says.
"We've got to bring CO2 levels down to 40% of what they are today by 2030, or so. And then to zero by 2050, and then negative after that. That's a massive undertaking but it's possible."
Keep these in mind as you contemplate the direction of the American government over the past 50 years and especially since the Obama election.
The Goals of Communism
(as read into the congressional record January 10, 1963, from "The Naked Communist" by Cleon Skousen)
1. U.S. acceptance of coexistence as the only alternative to atomic war.
2. U.S. willingness to capitulate in preference to engaging in atomic war.
3. Develop the illusion that total disarmament of the United States would be a demonstration of moral strength.
4. Permit free trade between all nations regardless of Communist affiliation and regardless of whether or not items could be used for war.
5. Extension of long-term loans to Russia and Soviet satellites.
6. Provide American aid to all nations regardless of Communist domination.
7. Grant recognition of Red China. Admission of Red China to the U.N.
8. Set up East and West Germany as separate states in spite of Khrushchev's promise in 1955 to settle the German question by free elections under supervision of the U.N.
9. Prolong the conferences to ban atomic tests because the United States has agreed to suspend tests as long as negotiations are in progress.
10. Allow all Soviet satellites individual representation in the U.N.
11. Promote the U.N. as the only hope for mankind. If its charter is rewritten, demand that it be set up as a one-world government with its own independent armed forces. (Some Communist leaders believe the world can be taken over as easily by the U.N. as by Moscow. Sometimes these two centers compete with each other as they are now doing in the Congo.)
12. Resist any attempt to outlaw the Communist Party.
13. Do away with all loyalty oaths.
14. Continue giving Russia access to the U.S. Patent Office.
15. Capture one or both of the political parties in the United States.
16. Use technical decisions of the courts to weaken basic American institutions by claiming their activities violate civil rights.
17. Get control of the schools. Use them as transmission belts for socialism and current Communist propaganda. Soften the curriculum. Get control of teachers' associations. Put the party line in textbooks.
18. Gain control of all student newspapers.
19. Use student riots to foment public protests against programs or organizations which are under Communist attack.
20. Infiltrate the press. Get control of book-review assignments, editorial writing, policymaking positions.
21. Gain control of key positions in radio, TV, and motion pictures.
22. Continue discrediting American culture by degrading all forms of artistic expression. An American Communist cell was told to "eliminate all good sculpture from parks and buildings, substitute shapeless, awkward and meaningless forms."
23. Control art critics and directors of art museums. "Our plan is to promote ugliness, repulsive, meaningless art."
24. Eliminate all laws governing obscenity by calling them "censorship" and a violation of free speech and free press.
25. Break down cultural standards of morality by promoting pornography and obscenity in books, magazines, motion pictures, radio, and TV.
26. Present homosexuality, degeneracy and promiscuity as "normal, natural, healthy."
27. Infiltrate the churches and replace revealed religion with "social" religion. Discredit the Bible and emphasize the need for intellectual maturity which does not need a "religious crutch."
28. Eliminate prayer or any phase of religious expression in the schools on the ground that it violates the principle of "separation of church and state."
29. Discredit the American Constitution by calling it inadequate, old-fashioned, out of step with modern needs, a hindrance to cooperation between nations on a worldwide basis.
30. Discredit the American Founding Fathers. Present them as selfish aristocrats who had no concern for the "common man."
31. Belittle all forms of American culture and discourage the teaching of American history on the ground that it was only a minor part of the "big picture." Give more emphasis to Russian history since the Communists took over.
32. Support any socialist movement to give centralized control over any part of the culture--education, social agencies, welfare programs, mental health clinics, etc.
33. Eliminate all laws or procedures which interfere with the operation of the Communist apparatus.
34. Eliminate the House Committee on Un-American Activities.
35. Discredit and eventually dismantle the FBI.
36. Infiltrate and gain control of more unions.
37. Infiltrate and gain control of big business.
38. Transfer some of the powers of arrest from the police to social agencies. Treat all behavioral problems as psychiatric disorders which no one but psychiatrists can understand.
39. Dominate the psychiatric profession and use mental health laws as a means of gaining coercive control over those who oppose Communist goals.
40. Discredit the family as an institution. Encourage promiscuity and easy divorce.
41. Emphasize the need to raise children away from the negative influence of parents. Attribute prejudices, mental blocks and retarding of children to suppressive influence of parents.
42. Create the impression that violence and insurrection are legitimate aspects of the American tradition; that students and special-interest groups should rise up and use united force to solve economic, political or social problems.
43. Overthrow all colonial governments before native populations are ready for self-government.
44. Internationalize the Panama Canal.
45. Repeal the Connally reservation so the United States cannot prevent the World Court from seizing jurisdiction over nations and individuals alike.
JANE FRANCIS/BAS
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