No. 84: Nov-Dec 1992
"An in situ Upper Permian fossil forest in the central Transantarctic Mountains near the Beardmore Glacier includes 15 permineralized trunks in growth position; the paleolatitude of the site was approximately 80° to 85° south. Numerous leaves of the seed fern Glossopteris are present in the shale in which the trunks are rooted. The trunks are perminealized and tree rings reveal that the forest was a rapidly growing and young forest, persisting in an equable, strongly seasonal climate -- a scenario that does not fit with some climate reconstructions for this time period."
Some models of the Permian climate, based on astronomical and meteorological parameters, have winter temperatures at the site averaging -30° to -40°C, with the average summer temperature at merely 0°C. This fossil forest is clearly at odds with these models.
(Taylor, Edith L., et al; "The Present Is Not the Key to the Past: A Polar Forest from the Permian of Antarctica," Science, 257:1675, 1992.)