Climate Central: We are standing on the edge of a new world where warming is poised to accelerate at rates unseen for at least 1,000 years.

That’s the main finding of a paper published Monday in Nature Climate Change, which looked at the rate of temperature change over 40-year periods. The new research also shows that the Arctic, North America and Europe will be the first regions to transition to a new climate, underscoring the urgent need for adaptation planning.

“Essentially the world is entering a new regime where what is normal is going to continue to change and it’s changing at a rate that natural processes might not be able to keep up with,” Steven Smith, a researcher at the Pacific Northwest National Laboratory, said.

Historical records show temperatures have typically fluctuated up or down by about 0.2°F per decade over the past 1,000 years. But trends over the past 40 years have been decidedly up, with warming approaching 0.4°F per decade. That’s still within historical bounds of the past — but just barely.

By 2020, warming rates should eclipse historical bounds of the past 1,000 years — and likely at least 2,000 years — and keep rising. If greenhouse gas emissions continue on their current trend, the rate of warming will reach 0.7°F per decade and stay that high until at least 2100. [Continue reading…]