A new international study that traces past temperatures in the Arctic back further than ever before claims that the Arctic is warmer than it has been at any other time in the past 2,000 years.

The study was published in last Thursday’s edition of the journal Science and gives not only mathematical climate models that indicate greenhouse gases are behind global warming, but also provides real world evidence to back up the claims.

Profession Darrel Kaufman, the lead author on the paper, said, “There are no other forcing factors at work other than the greenhouse gas composition of the atmosphere that could explain the dramatic warming that took place.”

Nearly three dozen scientists, along with Prof. Kaufman, studied data from lake sediments, tree rings and glacial ice deposits located at 23 different sites around the world in order to track the average summer temperature for each decade in the past two millennia. The time frame they chose to study is 1,600 years longer than any other study has looked at.

While the study shows that from Year 1 to around 1900 the Arctic summer temperatures were actually decreasing by about 0.2 C every 1,000 years, as soon as we hit the 20th century, things started to heat up in the Arctic. The research conducted suggests that four of the five warmest decades seen in the Arctic happened after 1950, with the warmest decade being 1999-2008.

Prof. Kaufman said,” The warming that we detected, particularly during the second half of the 20th century, is especially dramatic considered against the background of the previous nineteen.”

While he admits that there are still many unknowns about Earth’s climate, Prof. Kaufman thinks that the correlation between the results of his study and computer models gives more weight to the general consensus in the science community that greenhouse gases are the main cause of global warming.

 “Our study is among many others that have documented the dramatic change in climate that has taken place in the last 50 years. The evidence that humans play a role in climate change is now overwhelming. It’s time for policy makers to act decisively on regulating carbon emissions.”