Paper: Earth has been getting hotter for past 10,000 YEARS, contradicting studies that humans started global warming
The study argues previous research used contradictory ice core data
Scientists ran different computer simulations of climate influences
Each showed a notable global warming trend over last 10,000 years
And no physical forces, scientists say, could have been strong enough to overwhelm the warming trend
It argues that previous research that showed a cooling trend was wrong because it used contradictory ice core data
The research was undertaken by University of Wisconsin-Madison's Professor Zhengyu Liu.
'We have been building models and there are now robust contradictions', he said. 'Data from observation says global cooling. The physical model says it has to be warming.'
Scientists ran simulations of climate influences and each on revealed global warming occurring over the last 10,000 years.
Professor Liu explained that we know atmospheric carbon dioxide rose by 20 parts per million before the 20th century, and the massive ice sheet of the Last Glacial Maximum has been retreating.
These physical changes suggest that, globally, the annual mean global temperature should have continued to warm, even as regions of the world experienced cooling, such as during the Little Ice Age in Europe between the 16th and 19th centuries.
