Meteorologists make official stance unequivocal: Humans are main cause of climate change

The American Meteorological Society (AMS) has firmed up its definition of the relationship between climate change and weather events. The group has issued a statement that says the warming world is a fact beyond reproach, and that human activity -- despite some natural variability -- is the main force behind such changes. (KUSA-TV image)

"Warming of the climate system now is unequivocal," reads the statement. "Observations show increases in globally averaged air and ocean temperatures, as well as widespread melting of snow and ice and rising globally averaged sea level." The dominant cause of the warming since the 1950s is human activities, it went on, adding that their scientific finding is based on "a large and persuasive body of research." Read the complete AMS statement here.

A 2010 George Mason University study of working television meteorologists found that only 54 percent believed in climate change or global warming, 25 percent said it wasn't and 21 percent were not sure. About one-third (31 percent) said global warming was caused mainly by human activity. Read findings of the study here.

AMS Executive Director Keith Seitter explained that the society's most current climate change statement is "the result of hundreds of hours of work by many AMS members over the past year. It was a careful and thorough process with many stages of review, and one that included the opportunity for input from any AMS member before the draft was finalized." The statement continues: "It is clear from extensive scientific evidence that the dominant cause of the rapid change in climate of the past half century is human-induced increases in the amount of atmospheric greenhouse gases, including carbon dioxide (CO2), chlorofluorocarbons, methane, and nitrous oxide. The most important of these over the long term is CO2, whose concentration in the atmosphere is rising principally as a result of fossil-fuel combustion and deforestation." (Read more)