New research out of the University of Colorado Boulder indicates that the average summer temperatures during the last 100 years in the Eastern Canadian Arctic are the warmest of any century dating back 44,000 years.
The team of scientists, lead by Professor Gifford Miller of the department of geological sciences used dead moss clumps from receding ice caps on Baffin Island as their tiny clocks. Radiocarbon dating showed that the mosses had not been exposed to the elements since at least 44,000 to 51,000 years ago.
The results of this study offer the first, direct evidence that the present warmth in this region is greater than that from the early Holocene period (17,000 years ago) when the amount of the sun's energy reaching the Northern Hemisphere in the summer was 9% higher than today.
Key excerpts from the University of Colorado Boulder report......
Since radiocarbon dating is only accurate to about 50,000 years and because Earth's geological record shows it was in a glaciation stage prior to that time, the indications are that Canadian Arctic temperatures today have not been matched or exceeded for roughly 120,000 years, Miller said.
"The key piece here is just how unprecedented the warming of Arctic Canada is," said Miller, also a fellow at CU-Boulder's Institute of Arctic and Alpine Research. "This study really says the warming we are seeing is outside any kind of known natural variability, and it has to be due to increased greenhouse gases in the atmosphere."
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