I think it is happening, and that we probably don't have all the answers as to why. What seems more important, how will the human race respond? I think the most prudent course is to assume we can't stop the warming, try to predict what effects the climate change will have and spend our resources looking for ways to adapt. If we predict higher ocean levels and stronger hurricanes, maybe we look to move our populations out of harms way now rather than continually rebuild in foodplains and hurricane allies. If California winters will be wetter but warmer, forestalling our "natural" summer water storage in snowpack, maybe we should think about ways to capture water in other ways. By all means, put your homes on stilts, New Orleanians, and keep plywood around to cover your windows, Houstonites, and conserve water with dry landscaping and lo-flow toilets, Sacramentoans - but we need major, long term solutions to the effects of climate change. Spending our time and energy trying to stop something that may well be unstoppable just doesn't make sense to me. If the thermometer were swinging the other way, and scientists were of accord that another ice age would be upon us in the next ten years, and who knows for how long, how would we react?