TECH
01/02/2018 11:40 GMT

It has Been The Hottest Decade For Almost 11,000 Years

'In the absence of people, the trend would have been cooling,'

A new climate change study has found that across the US and Europe, the last 10 years have been around the warmest we’ve seen for almost 11,000 years.

The shocking revelation comes courtesy of a climate study being carried out by researchers from the University of Wyoming and took around five years to pull together.

Bryan Shuman, a UW professor in the Department of Geology and Geophysics, and Jeremiah Marsicek, a recent UW Ph.D. graduate in geology and geophysics both collected fossilised samples from over 642 lakes and pools.

David Foster
Little Pond, located in Royalston, Mass., was among 642 ponds or lakes in North America and Europe from which fossil pollen was collected to reconstruct temperatures. The reconstructions, which looked at climate in North America and Europe over the past 11,000 years, closely matched the climate simulations run by NCAR, which were conducted independently as part of separate projects.

“When we collect sediment from the bottom of the lake, we can recognise sequences of plants that grew in a given area based on the shape of the fossil pollen left behind,” Shuman explains. “Because different plants grow at different temperatures, we can constrain what the temperatures were in a given place at a certain time.”

From those samples they were able to create a temperature timeline that spanned all the way back to the last Ice Age.

By comparing those findings to more recent data, the two researchers made two very startling discoveries.

“I would say it is significant that temperatures of the most recent decade exceed the warmest temperatures of our reconstruction by 0.5 degrees Fahrenheit, having few ― if any ― precedents over the last 11,000 years,” Marsicek says.

“Additionally, we learned that the climate fluctuates naturally over the last 11,000 years and would have led to cooling today in the absence of human activity.”

So not only are we experiencing some of the warmest temperatures ever recorded but had humans not been around at all, the Earth might currently have been going through a period of cooling.

“In the absence of people, the trend would have been cooling,” Shuman says. “It does show that what has happened in the last 30 years ― a warming trend ― puts us outside of all but the most extreme single years every 500 years since the Ice Age.”

Not only will the results be another wake-up call for those still undecided about humanity’s impact on the Earth’s global temperature, but it also gives us a much clearer view of how the world behaves on a timescale far beyond our own lifespans.

“These new findings help us understand how the global climate system works over scales of decades to millennia and give us a new perspective from the distant past on recent and future climate changes.” says Jonathan Wynn, program director in NSF’s Division of Earth Sciences which helped fund the research.