"NASA will send up a big sun shade that will be in orbit between the earth and sun and deflect 2 or 3 percent of the sunshine back into space. It would be cheaper than the international space station"

James Lovelock envisions a large engineering solution to address planetary warming: deploying a vast sunshade into orbit between Earth and the Sun. The concept involves placing a structure at a stable point between the two bodies, likely the L1 Lagrange point, where gravitational forces and orbital motion would allow the sunshade to remain in a fixed position, effectively casting a partial shadow over the planet. By blocking or deflecting 2 or 3 percent of incoming solar radiation, such a structure could significantly reduce global temperatures and mitigate some of the worst effects of climate change, offering a potential form of solar radiation management.

The magnitude of this intervention is striking. Earth receives about 1,366 watts of solar energy per square meter at the top of its atmosphere; even a small reduction in this energy could offset the warming caused by greenhouse gases. Lovelock’s notion challenges conventional strategies, which often focus on reducing emissions, conservation, or adaptation. His sunshade would directly alter the planet's energy balance, representing a dramatic form of geoengineering.

The comparison to the International Space Station (ISS) is notable. The ISS is among humanity's most complex and expensive technological achievements, costing over $100 billion and involving years of international collaboration. Lovelock suggests that constructing and maintaining a sunshade capable of shading Earth could be accomplished at a lower cost than the ISS. This points not only to the feasibility of the idea in engineering and economic terms but also aims to shift perceptions about what is possible or necessary in the face of an existential crisis.

Lovelock’s statement provokes consideration of humanity’s readiness to intervene on such a massive scale. The proposal foregrounds the scale of intervention needed to correct climate trajectories and sparks debate about the ethics, risks, and unforeseen consequences of planetary-scale geoengineering, compared to more conventional, incremental approaches.