Global Temperatures Highest in 4,000 Years
"Global temperatures are warmer than at any time in at least 4,000 years, scientists reported Thursday, and over the coming decades are likely to surpass levels not seen on the planet since before the last ice age.
Previous research had extended back roughly 1,500 years, and suggested that the rapid temperature spike of the past century, believed to be a consequence of human activity, exceeded any warming episode during those years. The new work confirms that result while suggesting the modern warming is unique over a longer period.
Even if the temperature increase from human activity that is projected for later this century comes out on the low end of estimates, scientists said, the planet will be at least as warm as it was during the warmest periods of the modern geological era, known as the Holocene, and probably warmer than that. "
http://www.nytimes.com/2013/03/08/science/earth/global-temperatures-highest-in-4000-years-study-says.html?ref=world&_r=0