Fossil Arctic Animal Tracks Point to Climate Risks
COAL MINE SEVEN, Svalbard, Norway -- Fossils of a hippopotamus-like creature on an Arctic island show the climate was once like that of Florida, giving clues to risks from modern global warming, a scientist said.
Fossil footprints of a pantodont, a plant-eating creature weighing about 400 kg (880 lb), add to evidence of sequoia-type trees and crocodile-like beasts in the Arctic millions of years ago when greenhouse gas concentrations in the air were high.
"The climate here about 55 million years ago was more like that of Florida," Appy Sluijs, an expert in ancient ecology at Utrecht University in the Netherlands, said in Coal Mine Seven on the Norwegian archipelago of Svalbard.
"Where we are now was once a temperate rainforest," he said on Tuesday, at the end of a horizontal mine shaft 5 kms (3 miles) inside a mountain and 300 metres (600 feet) below the surface.
He pointed to a row of footprint impressions found in December in the roof of the mine north of Longyearbyen, the main settlement on the barren treeless Norwegian archipelago 1,000 km (600 miles) from the North Pole.
Sluijs said forests grew in the Arctic when carbon dioxide, the main greenhouse gas, was at about 1,000 parts per million in the atmosphere because of natural swings in the climate.
And he said such concentrations point to risks with surging modern emissions stoked by human use of fossil fuels -- greenhouse gas concentrations are at the highest in at least 650,000 years and rising fast.
"It's a worrying scenario for future global warming," he told a group of students studying climate change. The ancient warming was triggered by natural shifts, perhaps linked to volcanic activity and a thaw of frozen methane.
Sea levels 55 million years ago were about 100 metres higher than now -- Antarctica was free of ice.
"We are starting processes that will last for hundreds, perhaps thousands of years," he said of modern emissions from burning fossil fuels in power plants, factories and cars.
When Svalbard was hot -- the islands were also close to the North Pole 55 million years ago -- many parts of the globe near the equator would have been too hot for modern plants and animals that have adapted to a modern climate, he said.
Carbon dioxide levels are now at almost 390 per million in the atmosphere, up from 270 before the Industrial Revolution and rising fast. Sluijs said they could reach 1,000 parts per million by 2100 if not held in check.
The footprints were found by chance by two miners. "As far as we know there are only five pantodonts of this type found in the world," said Steve Torgersen, a mining expert.