A decade or so ago, when geophysicists and policy wonks started to talk about climate change rather than global warming, certain people seemed to think this represented some kind of insidious propaganda. Actually it just reflected an awareness that some of the consequences of global warming may be counter-intuitive or not what comes right to mind: increased winter precipitation, springtime flooding, more violent storminess, and so on.
During the past two years states in the U.S. Mid-Atlantic, northeastern and upper midwestern regions have had extraordinarily high and intense winter snowfalls. Spring snow melts have been greater and more rapid, with the Ohio and Mississippi basins now experiencing the worst flooding in close to a century. Weeks ago the Southeast was swept by tornadoes unlike anything most living people could ever remember, producing images reminiscent of the climate horror movie "The Day After Tomorrow." Climate change? So, in some sense, it seems.
"Although there is some uncertainty about future risks," says a major report issued by the National Research Council last week, "changes in climate and related factors have already been observed in various parts of the United States; and the impacts of climate change can generally be expected to intensify with increasing greenhouse gas emissions." The report notes that average U.S. temperatures have climbed two degrees Fahrenheit in the last 50 years, and that water levels are rising among many American towns and cities.
The report, "America's Climate Choice," makes favorable mention of greenhouse gas reduction efforts by cities, states, and regions, but says that a strong Federal policy would have much more impact. And if the United States is to live up to the commitment it made at Copenhagen in December 2009, where the agreed-upon accord promised to limit global increases in temperature to no more than 2 degrees Celsius by comparison with pre-industrial levels, there will have to be "a significant departure from 'business-as-usual' in how we produce and use energy." The most effective policy device, says the report, would be "a comprehensive, nationally uniform price on CO2 emissions, with a price trajectory sufficient to drive major investments in energy efficiency and low-carbon technologies."
The group that produced the NRC report was unusually diverse, as The New York Times noted. Though it included some stalwarts long associated with energy policy like Robert W. Fri and the its chairman Albert Carnesale, and some prominent climate experts like Susan Solomon and Robert H. Socolow, it also drew in people from the business community and from conservative policies, like Jim Gerringer, a former Wyoming governor now head of the Environmental Systems Research Institute in Cheyenne.