Econintersect: No, this is not a report of some global warming research projection. It is a fact that more than 50 million years ago the climate of earth was much warmer but more moderate than today and the poles saw temperatures that were very similar to the equator, with temperatures ranging from 50 – 77 degrees F (10 – 25 degress Celcius), according to research published last week in Nature. The period, known as the early Eocene has been referred to as the Eocene greenhouse, a warm analogue to the current earth. One characteristic of the period was that CO2 levels were 2-3 times as high as in the modern day. The entire Eocene period covered the time from about 56 million years ago up to about 34 million years ago and is the period in which the first modern mammals begain to emerge.
Click on picture to see enlarged view of Antarctica’s coast. See if you can spot the palm trees.
New findings by researchers drilling in the ocean floor off East Antarctica have revealed pollen and spores associated with near-tropical forests that included palm trees. One remarkable finding is that the temperature profile that is defined by the research does not go below about 50 degrees F (10 degrees C) during the long polar “winter” night. The researchers indicate that their findings may be valuable in interpretign what future climates may be like for earth. From the abstract:
The warmest global climates of the past 65 million years occurred during the early Eocene epoch (about 55 to 48 million years ago), when the Equator-to-pole temperature gradients were much smaller than today1, 2 and atmospheric carbon dioxide levels were in excess of one thousand parts per million by volume3, 4. Recently the early Eocene has received considerable interest because it may provide insight into the response of Earth’s climate and biosphere to the high atmospheric carbon dioxide levels that are expected in the near future5 as a consequence of unabated anthropogenic carbon emissions4, 6
An article at the BBC has an interview quote from one of the study’s co-authors:
“There are two ways of looking at where we’re going in the future,” said a co-author of the study, James Bendle of the University of Glasgow.
“One is using physics-based climate models; but increasingly we’re using this ‘back to the future’ approach where we look through periods in the geological past that are similar to where we may be going in 10 years, or 20, or several hundred,” he told BBC News.
Previous research had found that the Arctic Ocean was once a subtropical shallow sea in the same early Eocene period.
- Persistent near-tropical warmth of the Antactic continent during the early Eocene epoch (Jorg Pross, et al, Nature, 02 August 2012)
- Palm tress ‘grew on Antarctica’ (Jason Palmer, BBC, 01 Aiugust 2012)
- North Pole ‘was once subtropical’ (Alex Kirby, BBC, 07 September 2004)
Hat tip to Naked Capitalism.