claim: A key study published in the Journal of Climate this year by Bjorn Stevens of the Max Planck Institute for Meteorology in Hamburg, Germany, found that the cooling impact of sulfate emissions has held back global warming less than thought till now
evidence: This phrase next appeared in a November 1957 report in The Hammond Times which described Roger Revelle's research into the effects of increasing human-caused CO 2 emissions on the greenhouse effect : a large scale global warming, with radical climate changes may result.