Palms grew in ice-free Arctic 50 million years ago: study

By Alister Doyle, Environment Correspondent

OSLO (Reuters Life!) - Palms flourished in the Arctic during a brief sweltering period about 50 million years ago, according to a study on Sunday that hints at big gaps in scientific understanding of modern climate change.

The Arctic "would have looked very similar to the vegetation we now see in Florida," said Appy Sluijs of Utrecht University in the Netherlands who led an international study. Evidence of palms has never been found so far north before.

The scientists, sampling sediments on a ridge on the seabed that was about 500 km (300 miles) from the North Pole 53.5 million years ago, found pollens of ancient palms as well as of conifers, oaks, pecans and other trees.

"The presence of palm pollen implies that coldest month mean temperatures over the Arctic land masses were no less than 8 Celsius" (46.40F), the scientists, based in the Netherlands and Germany, wrote in the journal Nature Geoscience.

That contradicts computer model simulations -- also used to predict future temperatures -- that suggest winter temperatures were below freezing even in the unexplained hothouse period that lasted between 50,000 and 200,000 years in the Eocene epoch.

Palms are quickly killed by frost.

Sluijs said that it was also striking that palms, which do not lose their leaves in winter, grew in an area where the sun does not shine for about five months. Experiments with modern palms indicate that they can survive prolonged darkness.

SURPRISES