Using a coring sampling technique similar to the way they determine the age of different types of rock, scientists have now been able to estimate the Arctic summer temperatures for the last 2,000 years. They also used data garnered from tree rings and other glacial ice. By plugging the collected temperature data into a computer simulation, they were able to see a 2,000 year trend showing that the Arctic temperatures would actually be decreasing, were it not for the greenhouse gases we are producing.The reason for this cooling stems from the Earth’s axis and it’s relativity to how close the planet gets to the Sun during an orbit. The amount of sunlight that reaches the Arctic has been getting steadily lower, resulting in the reduced temperature. In the year 2000, by their estimates, summer in the Arctic should have been about 2.5 degrees cooler than it actually was.
Previously, there was only about a 400 year window of data available to examine. The new research shows that the cooling continued until about 1900, at which time the trend changed from -1 to +1 during the summer, which is a significant difference when ice is in the equation.
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