It's us

The  Intergovernmental Panel on Climate Change just issued its latest report on the state of scientific knowledge about climate change.  The report's main headline conclusion is that we are the principal cause of a significant and rapid warming of the planet.  If you paid attention to the last report this conclusion should come as no surprise.  There is plenty of dire predictions in the report, and a good deal to be pessimistic about, but as Andrew Revkin points out in his dot earth blog, one of the report's findings provides a significant measure of hope: 

By the mid-21st century the magnitudes of the projected changes are substantially affected by the choice of emissions scenario.

Not all is lost or preordained.  We can still shape our future.  The powerful combination of free enterprise, innovation, science, technology, and dynamic and responsive political systems created the climate quandary we are in.  It can also solve it, if we have the will.

While pondering those lofty issues, you might enjoy Revkin's carbon soundtrack: