Despite their calm demeanors, Kerry Emanuel and Ernie Moniz impart grave and pressing concerns about global warming to this Museum gathering.

Emanuel admits that he was still a skeptic 20 years ago, but that detailed analysis of the earth’s climate record, and sophisticated modeling have convinced him and a vast majority of his colleagues that we’re witnessing a rapidly changing environment due to greenhouse gas emissions. The world is in the process of doubling its carbon dioxide emissions over the pre-industrial value of 280 parts per million. Experts project a 2-5 degree increase in the Earth’s temperature, in our children’s lifetimes.

“What keeps some of us awake at night and in my mind drives us to take seriously why we have to deal with energy, is surprises. Things that we’re worried about that might happen, that we don’t know enough to rule out. These are low probability but high impact events that anyone with children worries about,” says Emanuel. One such surprise might be the rapid melting of the Greenland ice cap (which vanished once before, in the distant past, amazingly fast). If all this ice melts into the world’s oceans, says Emanuel, “you’re talking about seven meters of sea level rise: say goodbye to Cape Cod, southern Florida, a lot of Manhattan.” Emanuel, a hurricane specialist, also foresees much greater intensity of hurricanes, as the world warms up.

This clear and present danger of climate change must force nations to control fossil fuel use, says Ernie Moniz. If we do nothing at all, carbon dioxide emissions will double over their pre-industrial values in 50 years -- a point of no return. Yet the task of completely altering our energy infrastructure in this timeframe “certainly violates no law of physics,” says Moniz. We must be much more efficient in use of energy, especially in our residential and commercial buildings; we must find alternative transportation fuels; and we must achieve carbon-free or carbon-light electricity. There is no single “silver bullet” to wean us from fossil fuel addiction, and going from small-scale to large-scale production of energy alternatives will prove tricky.

Just as important, says Moniz, to get going on this new portfolio of technologies will require political will: “There must be a policy put in place relatively soon that one way or another attaches a price to greenhouse gas emissions,’ and encourage the market introductions of new forms of energy. Moniz believes that for the U.S., reengineering the economy toward energy independence plays to our technological strengths, and aligns environment and security interests.