Martin Rees writes: Consider this scenario: Suppose astronomers had tracked an asteroid, and calculated that it would hit the Earth in 2080, 65 years from now — not with certainty, but with, say, 10 percent probability. Would we relax, saying that this is a problem that can be set aside for 50 years, since people will by then be richer, and it may turn out that it misses the Earth anyway? I do not think we would. There would surely be a consensus that we should start straight away and do our damndest to find ways to deflect it, or mitigate its effects.

Why do our governments, in contrast, respond with torpor to the climate threat? It’s because concerns about future generations (and about people in poorer parts of the world) tend to slip down the agenda. And of course because the hardest challenges get parked in the “too-difficult box” rather than reacted to. The task of weaning the world away from dependence on fossil fuels is indeed a daunting one. I’m rather pessimistic about “top-down” attempts to constrain emissions, like the UN conference in Paris this year. It’s far more realistic to push forward with new technologies so that they can compete economically with fossil fuels.

The impediment to “decarbonizing” our economy is that renewable energy is still expensive to generate. Moreover, power from the sun and wind is intermittent so we need cheap ways to store it on a large scale. Fortunately, technology in solar energy and batteries is proceeding apace. Along with a group of colleagues, I have been promoting a campaign to accelerate it further. [Continue reading…]