Global Warming or Cooling?
Decade-long cooling trends can occur within long-term global warming
Some Web sites, blogs, and media articles have pointed to the fact that average global temperature has not risen since 1998 as evidence against anthropogenic global warming. Although most climate scientists recognize the statistical insignificance of such short-term trends, Easterling and Wehner (2009) noted that some segments of the public do pay attention to them. To quell such objections, they argued that such short periods are not meaningful in the context of long-term climate change. The authors analyzed the observed globally averaged surface air temperatures for the period 1901—2008 as well as several climate model simulations for the twentieth and 21st centuries, including anthropogenically forced models. They plotted the probability distribution functions for decadal temperature trends and found that in the observed record and all models, decade-long periods of cooling can occur even within a strong overall warming trend. The authors expect that due to the natural variability of the real climate, in the 21st century there will probably be some multiyear periods of cooling or constant temperature within longer-term anthropogenic global warming. full article available
Some Web sites, blogs, and media articles have pointed to the fact that average global temperature has not risen since 1998 as evidence against anthropogenic global warming. Although most climate scientists recognize the statistical insignificance of such short-term trends, Easterling and Wehner (2009) noted that some segments of the public do pay attention to them. To quell such objections, they argued that such short periods are not meaningful in the context of long-term climate change. The authors analyzed the observed globally averaged surface air temperatures for the period 1901—2008 as well as several climate model simulations for the twentieth and 21st centuries, including anthropogenically forced models. They plotted the probability distribution functions for decadal temperature trends and found that in the observed record and all models, decade-long periods of cooling can occur even within a strong overall warming trend. The authors expect that due to the natural variability of the real climate, in the 21st century there will probably be some multiyear periods of cooling or constant temperature within longer-term anthropogenic global warming. full article available
About
Badge
Music
© 2009 Created by Diana Boase on Ning. Create Your Own Social Network
