“Yet [he] advances it as a last resort, despite the obvious, much safer things we can do now,” he said. “It shows the recurrent mirage of a silver bullet solution to climate change is often a sign of despair at world leaders’ unwillingness to seriously tackle carbon emissions. Every new technology in this field comes with issues and if they become an excuse for more foot-dragging on slashing carbon pollution, they will be harming the climate before even research is done.”
However, Rees insisted that considering geoengineering would not be a way to avoid the need for reducing carbon emissions. He said the world also needs to make a commitment to developing clean energy — extracting and storing power from wind, tides, biofuels, solar or nuclear — that matches the ambition of NASA’s Apollo moon landings in the 1960s and 1970s.
“It may take 50 years to decarbonize the world’s power generation, but this could be achieved if we start now,” he said.
Looking ahead in his own field of astronomy, Rees said he was excited by the regular discovery of planets orbiting other stars. In the past decade, space telescopes such as NASA’s Kepler have pushed the number of planets scientists know about into the thousands, but they predict there are probably many billions in our galaxy alone, and some of them could be twins of Earth.
With ever-improving instruments, he said scientists who are now at the start of their careers may be able to answer the question of whether there is life beyond Earth.
Back on our own planet, Rees also called for a more brotherly attitude from his fellow scientists to those of faith. Science, he said, is the one culture that is truly global and should transcend all barriers of nationality and religion.
“The scientists who attack mainstream religion, rather than striving for peaceful coexistence with it, damage science, and also weaken the fight against fundamentalism, but that’s a theme for another talk,” he said.