<p>In what&#39;s being called &quot;the most comprehensive report ever on climate change,&rdquo; The National Research Council, an arm of the National Academy of Sciences, issued three reports. The reports describe the case for a harmful human influence on the global climate as overwhelming and argue for strong immediate action to limit emissions of climate-altering gases in the United States and around the world&mdash;including the creation of a carbon pricing system.</p>