Climate to Warm Beyond Levels Seen for 11,300 Years

http://www.climatecentral.org/news/climate-to-warm-beyond-levels-seen-for-at-least-11300-years-15701
A new reconstruction of the Earth's climate history — dating back 11,300 years — found that the planet has rarely been warmer than it is today during that time, and that temperatures are likely to climb into unprecedented territory by 2100, due to increasing amounts of planet warming greenhouse gases in the air.

The data shows there was a long, gradual warmup for about 5,000 years, then a plateau of warm temperatures, and then an equally gradual cooling trend until about 200 years ago.

Marcott said that is in line with the gradual changes known as Milankovitch Cycles, caused by the Earth’s tilt and its orbit around the Sun. Based on where we are in those cycles, Marcott said, the planet should still be cooling. Not only is the Earth warming, it is warming much faster than a Milankovitch Cycle could possibly explain. “The temperature change is both too abrupt, and going in the wrong direction, to be natural” Marcott said.

By Michael D. Lemonick
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