LONDON, Sept. 1 (UPI) -- Researchers at the University of East Anglia in Britain say the Earth appears to have been warmer since 1980 than at any time in the last 1,800 years.
Professor Philip Jones, of the university's climatic research unit, and colleagues reconstructed the global climate using data derived from ice cores, vegetation and other records.
In a study published in the journal Geophysical Research Letters, the researchers examined the trunks of ancient trees, cores taken from the ice caps of Greenland and Antarctica and historical records from the Netherlands, Switzerland and China, as well as elsewhere.
The research indicates that in the last 20 years, the Earth's temperature has warmed at least 0.2 degree Celsius (0.36 degree Fahrenheit).
"It just shows how dramatic the warming has been in recent years," Jones told the BBC. "You can't explain it in any other way -- it's a response to a build-up of greenhouse gases in the atmosphere."
Jones discounts skeptics who say climate fluctuates naturally and that man's influence is negligible.
