robert stavins, let me start with you. this report stresses the urgency of doing something now, implementing new policies. give us an example of a policy that the united states needs to implement in the near term. >> well, jude, what's become clear is that for this country, for the united states, the only approach that conceivably would achieve meaningful emissions reductions such as those that are talked about in the new report from the new intergovernmental panel on climate change would be a new system, might be a cabin trade system as has been denigrated and passed the house but not the senate or perhaps a revenue neutral carbon tax but something pervasive throughout the economy and send the right price signals. >> woodruff: is this something you think lawmakers could embrace in today's political environment? >> well, in today's political environment what is feasible is what is happening in the united states and that is that the administration is taking some action under existing regulations and through executive orders