Clouding the debate

Science | Meteorologist and former NASA scientist Roy Spencer believes global warming alarmists may be asking the wrong questions | Daniel James Devine

Photo by Billy Weeks

Roy W. Spencer believes in global warming. He just thinks it's the Earth's fault. Climate debate can be hazardous, but this former NASA scientist is preeminently qualified to weigh in: In 1989 Spencer and colleague John Christy pioneered a method of measuring global atmosphere temperature using satellite microwave sensors, an achievement that earned awards from NASA and the American Meteorological Society. Today Spencer oversees a research team for an Earth-monitoring satellite from his office at the University of Alabama in Huntsville. In his spare time he writes books throwing cold water on the idea that global warming is mostly caused by people.

His latest, The Great Global Warming Blunder: How Mother Nature Fooled the World's Top Climate Scientists (Encounter Books, 2010), lays out Spencer's research into the effect of clouds on atmosphere temperature. Spencer became particularly interested in clouds when he learned about a key assumption climate modelers make when predicting future global warming: Warmer average temperatures will result in reduced cloud cover. What if that assumption had it backwards? What if reduced cloud cover were causing the warmer temperatures? "If you get that wrong," Spencer told me when I met him at a conference this summer, "then you get a totally wrong answer in terms of how much warming there will be as a result of us putting more greenhouse gases in the atmosphere."