[The following is an exact transcript of this podcast.]

"The energy we use can sustain our planet, or destroy it." So said U.S. President Barack Obama yesterday while addressing the United Nations, talking about the twin challenges of climate change and energy consumption.

His counterpart from China, Hu Jintao, offered a similar perspective, touting his country's headlong rush to cleaner energy sources, particularly hydropower and nuclear power. He also promised an unspecified cut in carbon intensity—a measure of greenhouse gases emitted per widget produced.

And former U.N. Secretary General Kofi Annan offered the following advice to an audience at Columbia University during Climate Week: "Set an example yourselves, if you can bicycle, if you can walk. If you don't have to drive don't do it."

But are bicycles or even carbon intensity cuts enough? No.

Ongoing science reveals that climate change is worse than we feared. "On all kind of parameters they looked into they could just say things have grown worse since the IPCC report came out." That's Danish minister Connie Hedegaard, leader of the diplomatic push for a global treaty at Copenhagen this December.

World leaders are running out of time to come up with a solid solution before that meeting. But addressing the energy challenge, which would go a long way toward addressing the climate change, is ultimately about global moral and economic standing. As President Obama said back in April, "The nation that leads the world in creating new energy sources will be the nation that leads the 21st-century global economy."

Unfortunately, as the president observed yesterday, “The magnitude of our challenges has yet to be met by the measure of our actions." 

—David Biello