Jim Inhofe: “This data show a warming to about 1940, little change from 1940 to the mid-1970s, and then further warming. Senator…”

“This data show a warming to about 1940, little change from 1940 to the mid-1970s, and then further warming. Senator Inhofe implies that these changes are inconsistent with the global warming hypothesis and with climate models. This is categorically incorrect. In order to understand these observed changes, it is necessary to consider all likely causal factors, both human-induced and natural. Human-induced factors include the warming effects of greenhouse gases and the cooling effects of sulfate aerosols. Natural factors include changes in the output of the sun, effects of explosive volcanic eruptions like Mount Pinatubo in 1991.”