Carbon-free energy is simply something we have to do. The time for talk is past. If we turn around net carbon emissions by 2020 rather than 2040, we get another 2° of fever rather than 3° - and that's a big difference.

Our CO2 mixes with everyone else's within a year, then hangs around for centuries like a shroud.

You can always spot the pioneers by the arrows in their backs.

Carrying on as usual carries enormous risks, condemning today's students to a world of constant insecurity and frequent catastrophes.

Anyone who would tackle our current addiction to fossil fuels is going to have to maneuver around denial.

Perhaps we should put up posters in such places reminding people that where they stand was underwater the last time that the Earth ran a 3°F fever.

Unless we redesign our civilization in numerous ways, all of the science in the world won't save us.