One aspect of this problem suggests itself to me. It is that the
elimination of sea ice will allow a robust growing season as both the
surface water could quickly warm and the atmosphere as well. It is
quite different that the actual tree line controlled by elevation.
The fact remains that warm conditions must be available for long
enough, yet twenty four hour sunlight picks it up pretty quick. It
also sounds like this all occurred pre Ice Age so no significant ice
may even have existed.
Certainly we have evidence of that and migration could deal with the
critters involved as we are then describing a seasonal influx of warm
water. What we think we know today could well be badly of the mark.
Nunavut’s
mysterious ancient life could return by 2100
Posted by TANNAncient
Environment
Global climate change
means that recently discovered ancient forests in Canada's extreme
north could one day return, according to Alexandre Guertin-Pasquier
of the University of Montreal's Department of Geography, who is
presenting his findings at the Canadian Paleontology Conference in
Toronto today.
"According to
the data model, climate conditions on Bylot Island will be able
to support the kinds of trees we find in the fossilized forest
that currently exist there, such as willow, pine and spruce. I've
also found evidence of a possible growth of oak and hickory near the
study site during this period," Guertin-Pasquier said.
"Although it would of course take time for a whole forest to
regrow, the findings show that our grandchildren should be able to
plant a tree and watch it grow."
The fossilized forest found on Bylot Island in Nunavut is between 2.6 and 3 million years old according to estimations based on the presence of extinct species and on paleomagnetic analyses. Paleomagentic analysis involves looking at how Earth's magnetic field has affected the magnetic sediment in rocks -- like a compass, they turn to follow the magnetic poles. Scientists can use this information to date rocks as the history of the movement of the magnetic poles is relatively well known.
Wood samples in the ancient forest have been preserved throughout the eons in peat and by permafrost. "We studied the sediments in the forest and discovered pollen that are usually found in climates where the annual average temperature is around 0 degrees Celsius or 32 Fahrenheit," Guertin-Pasquier said. By comparison, current average conditions on Bylot Island are around -15°C ( 5°F). The samples were taken from few drill holes 10 cm in diameter of one to two metres deep. The harshness of the Arctic winter and the remoteness of the forest mean that scientists have very little opportunity to delve into its secrets.
Even during the summer, the Guertin-Pasquier and his colleagues had to endure extreme conditions such as 80 km/h winds. "There is so much mystery that surrounds this forest -- for example, how these trees managed to survive the relentless dark of the Arctic winter," he said, adding that the next steps for this line of research could include looking more closely at other plant remains in order to get a better understanding of what the local flora was.
This research was financed in part by the Polar Continental Shelf Program, Fonds de recherche du Québec -- Nature et technologies, and the Natural Sciences and Engineering Research Council of Canada programs.
Source: Universite de Montreal via Newswise [September 21, 2012]
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