Is the Earth's Climate Warming or Cooling?

As Congress scrutinizes new energy and climate legislation, many seem to be asking: Is it getting cooler or warmer? The answer, according to a new study, is that we need to concentrate on the long-term trend, which points to an overall warming tendency over these past hundred years. The great majority of climate scientists agree that it's getting warmer in many places around the world. The cause, they also agree, is heat-trapping carbon dioxide produced by human technology. But how does this square with the observed fact that over the past decade world temperature has actually stayed the same, or even gone down? Two scientists, Michael F. Wehner and David R. Easterling, show that such decade-long fluctuations are quite common in weather history. From day to day, season to season, and year to year, the weather shows great variability thanks to natural factors like capricious wind patterns and ocean currents. Changes in climate -- that is, changes in typical weather conditions over long periods of time -- are more difficult to assess. These short-term changes, say the scientists, must be differentiated from long-lasting, consequential trends in order to determine the role of human activities in shaping climate and to formulate industrial policy -- such as imposing a tax on carbon emissions...Fox News