Global Warming: Is the Science Settled Enough for Policy?

Dr. Stephen Schneider, an expert on global warming, recently gave a talk at the University of Arizona.

I didn’t get to go, but this is something that matters to me, so here’s some more information, courtesy of the press release announcing Dr. Schneider’s appearance, plus some of my hyperlinks.

Dr. Stephen Schneider, a nationally renowned climate change researcher and professor in Environmental Biology and Global Change at Stanford University, founder and editor of the journal - Climatic Change, authored and co-authored over 450 scientific papers, written numerous books on climate change, etc.

In the Fourth Assessment Report of the UN-sponsored Intergovernmental Panel on Climate Change (which shared the 2007 Nobel Peace Prize), Working Group I states that warming is “unequivocal” and it is “very likely” that human activities are responsible for most of the warming of recent decades. The same report says warming to 2100 is “likely” to be 1.1 -6.4 degrees C. Working Group II says 1.5 2.5 degrees C warming could commit 20-30% of known species to extinction (but only assigns this about a 50% chance). So, what is settled? Some projections are well established, some have competing explanations, yet others are speculative. Thus policy is a risk management judgment, just like most other complex socio-technical systems problems.

There is strong consensus that the increasing numbers of people in the world, demanding higher standards of living, and using cheap, available technologies (e.g. burning coal, and driving gas-consuming large automobiles) will double or triple the carbon dioxide content in the atmosphere by 2100. This implies many potentially serious impacts, though not all are negative. However, the distribution of these impacts is uneven, with most severe effects being experienced in poorer, warmer places, high mountains, polar regions, or in “hurricane alley.” Local, regional, and international actions are already beginning and much more could be done if there were political will to substantially reduce the magnitude of the risks.