Global Warming Over the Past 50 Years Likely Due to Increase in Greenhouse Gases

Summary

A paper published in the May issue of the Journal of Climate and authored by an international group of scientists, some of whom are funded DOE/BER reviews evidence, or lack thereof, of anthropogenic and natural external influences on climate. The review presents evidence from a number of investigators of the detection of greenhouse warming in data for global and continental surface temperature, in reconstructions of temperature over the past millenium, in ocean heat content, in atmospheric circulation, and temperature of the free atmosphere. The authors conclude that observed climate changes are very unlikely to be due only to natural internal climate variability, and are consistent with climate model simulations. This recent research supports and strengthens the IPCC Third Assessment Report conclusion that most of the global warming over the past 50 years is likely due to the anthropogenic increase in greenhouse gases.