A new analysis of 2,000 years of tree ring data has quickly made climate change deniers’ list of greatest hits to the theory of manmade global warming.
The tree rings “prove [the] climate was WARMER in Roman and Medieval times than it is now,” the British newspaper the Daily Mail reported last week, “and [the] world has been cooling for 2,000 years.”
“Our study doesn’t go against anthropogenic global warming in any way,” said Robert Wilson, a paleoclimatologist at the University of St. Andrews in Scotland and a co-author of the study, which appeared July 8 in the journal Nature Climate Change. The tree rings do help fill in a piece of Earth’s complicated climate puzzle, he said.
So, what exactly did the study find? Instead of using the width of trees’ rings as a gauge of annual temperatures, as most past analyses of tree rings have done, Wilson and his fellow researchers tracked the density of northern Scandinavian trees’ rings marking each year back to 138 B.C. They showed that density measurements give a slightly different reading of historic temperature fluctuations than ring width measurements, and according to their way of reckoning, the Roman and medieval warm periods reached higher temperatures than previously estimated.
According to Gavin Schmidt, a NASA climate scientist, the tree rings show what mounds of other data have shown as well: For the past few millennia, Earth’s northern latitudes had been cooling down overall. But Wilson, Schmidt and the vast majority of climate scientists agree: human-caused warming of the entire globe now overwhelms those subtle, regional heat redistributions. World temperatures are now pushing in only one direction: up.
How can we minimize the effects of human-caused warming in our world today? Do you believe in the results of this new tree ring study?
Image: Live Science