Recent Global Temperature Rise is Fastest in 11,000 Years since Last Ice Age

There's an increasing amount of evidence that the climate has dramatically warmed up over the past century, and now a new study examining 11,000 years of climate temperatures shows the Earth is head towards an even more significant rise in heat.

For a new study released Thursday in the journal Science, a research team from Harvard and Oregon State University looked at the fossils of tiny marine organisms, ice cores and tree rings to reconstruct global temperatures back to the end of the last ice age 11,300 years ago. Scientists learned that the rise in temperatures have been unmatched in at least the past 4,000 years. The study was largely in alignment with other regional studies that looked at the same period of time - the Holocene era.

The Holocene, which began around 12,000 years ago, marked a large increase in global temperatures where ice sheets across the northern hemisphere melted. This is believed to have provided the opportunity for the rise of human kind, about 8,000 years ago.

"We already knew that on a global scale, Earth is warmer today than it was over much of the past 2,000 years," says Oregon State University post-doctoral researcher Shaun Marcott. "Now we know that it is warmer than most of the past 11,300 years. This is of particular interest because the Holocene spans the entire period of human civilization."

The Earth, on average, has cooled about 1.3 degrees Fahrenheit over the past 5,000 years. Now in a dramatic turn around, it has begun to warm 1.3 degrees in the past 100 years. The largest changes are visible in the northern hemisphere, where there are more land masses and greater human populations.

Orbital forcings and temperatures did rise sharply at the end of the ice age, but they then remained relatively stable for about 5,000 years at about 0.6°C above the temperature of the last 1,500 years. 

Scientists warn that by 2100, the Earth will be warmer than ever before if emissions continue as currently predicted until that time.  As a result, global temperatures will rise "well above anything we've ever seen in the last 11,000 years," they warned.