US climate researchers say average global temperatures have been higher in the last decade than at any time during most of the previous 11,300 years. In a study published by the Journal Science, researchers from Oregon State University and Harvard University, write about the Holocene era, a relatively balmy period that began after the last major ice age ended and encompasses all of recorded human history. The researchers say the decade 2000-2009 was one of the warmest since modern record-keeping began, and they forecast the planet will be warmer in 2100 than it has been at any time in those 11,300 years, The Wall Street Journal reported Thursday. A 1-degree temperature variation that took most of those 11 millennia to occur has been replicated in just 150 years, beginning with the early days of the Industrial Revolution, the researchers said. The suddenness of the shift in temperature is at odds with the long-term trend, strongly suggesting the change is attributable to human activity, they said. "What's different is the rate of change," Oregon State paleoclimatologist Shaun Marcott said. "What we've seen over the past 150 years is much greater than anything we saw in the past 11,000 years."