North Pole had sub-tropical seas because of global warming
AFP on Yahoo ^ | 9/7/04 | AFP - Paris

PARIS (AFP) - The North Pole once had a balmy, sub-tropical sea
because of extreme global warming, according to European scientists
who have carried out the world's deepest drilling into ancient
sediment on the far northern seabed.

Cores retrieved from up to 430 metres (1,397 feet) below the seafloor
in waters 1,300 metres (4,550 feet) deep show that, for a brief period
which occurred around 55 million years ago, the Arctic Ocean was
around 20 C (68 F), compared with today's typical average temperature
of minus 1.5 C (29.3 F), they said on Tuesday.

"It occurred during a period called the Palaeocene-Eocene thermal
maximum, which was already known as a warm period," Andy Kingdon of
the British Geological Survey (BGS) told AFP.

"What no-one expected was how much warmer it really was. That is a
huge surprise."

The BGS joined other scientific agencies in a 12.5-million-dollar
(10.40-million-euro) initiative called the European Consortium for
Ocean Research Drilling (ECORD).

Under it, a Swedish-flagged, Norwegian-operated drillship ventured to
within 238 kilometers (148 miles) close to the North Pole, protected
by a Russian and a Swedish icebreaker, which broke up sea ice around
the vessel as it drilled into the sediment.

The evidence of big climate change comes in the form of fossilised
marine plants and animals which died out en masse within a relatively
short time because they could not cope with the surge in temperatures.

The cores also revealed a band of fossilised extinct algae that only
lived in sub-tropical conditions.

"The early history of the Arctic basin will be re-evaluated based on
the scientific results collected on this expedition," one of the
mission's chief scientists, Jan Backman, a professor at Stockholm
University, said.

The expedition returns to Tromso, Norway on September 14 and its
members will meet in Bremen, Germany, in November to assess the
results.

Although the data is only preliminary, the scientists "are absolutely
confident" in their conclusion about the massive temperature swing,
said Kingdon.

"This is convincing proof that global warming has a planetary-wide
effect, having a major impact on locations even as distant as the
North Pole."

As for what have caused the big warming during this period, two
theories are being aired, both based on the greenhouse principle in
which gases were released into the atmosphere, trapping the Sun's
heat.

One is that gigantic volanic eruptions disgorged billions of tonnes of
carbon dioxide (CO2) into the air; the other is that frozen methane,
held under layers of seabed sediment, was released and melted, also
causing a runaway greenhouse effect.