The White House quietly released a report with a striking conclusion during the news dead zone right before the July Fourth weekend: It’s not a horrible idea to research ways to block the sun’s rays from further heating the planet. But that doesn’t mean President Joe Biden’s team is ready to push it as a solution to climate change. Congress had mandated the report — a fact the White House made sure to emphasize in the title, text and accompanying statement. Still, by offering cautious support to geoengineering research, the report could bring efforts once confined to the realm of science fiction into mainstream debate, writes Corbin Hiar. Limiting how much sunlight hits the Earth is a potentially effective way to combat global warming. But the side effects could be disastrous, some scientists say, and the idea has generated fierce backlash from all corners of the political and scientific worlds. How it works One approach outlined in the 44-page White House document is to increase the number of aerosol particles in the atmosphere that reflect light away from the planet. Other methods entail increasing cloud cover over oceans to stop the sun from warming them and reducing the amount of high-flying clouds, which trap heat in the Earth’s atmosphere. But each plausible way to cool the planet comes with serious risks, the report says. Modifying sunlight could alter global weather patterns, disrupt food supplies and affect human health and biodiversity, to say nothing of the geopolitics of coordinating a global agreement on deployment. And if the intervention was ever halted, it could lead to abrupt and extreme warming. A tepid approach The White House declined to comment to Corbin on the record. But it made abundantly clear in a statement accompanying the report that “there are no plans underway to establish a comprehensive research program focused on solar radiation modification.” Still, the very existence of a White House report on such a divisive issue is remarkable, experts told Corbin. The document emphasized the importance of comparing the risks associated with solar radiation modification with the present dangers of an increasingly hotter planet — opening the door to more study. It also comes as European policymakers are signaling an openness to discussing whether and how humanity could limit heating from the sun.
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