So the latest Awake mentions the following:
Fossilized pollen and spores recovered from seabed sediment reveal that the Antarctic once supported palms and near-tropical forests. During the so-called “Eocene greenhouse period,” winters were mild and “essentially frost-free” and temperatures at the poles were not vastly different from those at the equator.
I suspect this is referring to the following research:
http://www.bbc.co.uk/news/uk-scotland-glasgow-west-19080850
I also suspect the Watching The World snippet is implying that the world used to have a more constant temperature as per the Witness myth re the pre flood water canopy. It's a shame therefore that the samples they refer to are 50 million years old. I guess they assume that few people will actually bother typing "Eocene greenhouse period" into google....