The Guardian reports:

As global heating escalates, the US government has set out a plan to further study the controversial and seemingly sci-fi notion of deflecting the sun’s rays before they hit Earth. But a growing group of scientists denounces any steps towards what is known as solar geoengineering.

The White House has set into motion a five-year outline for research into “climate interventions”. Those include methods such as sending a phalanx of planes to spray reflective particles into the upper reaches of the atmosphere, in order to block incoming sunlight from adding to rising temperatures.

The work is required by Congress. It is “not new research, but a report that highlights some of the key knowledge gaps and recommendations of priority topics for relevant research”, said a spokesperson for the White House’s office of science and technology policy, adding Joe Biden’s administration wants “effective and responsible CO2 removal” as well as deep cuts to greenhouse gas emissions.

Several American researchers, somewhat reluctantly, want to explore options to tinker with the climate system to help restrain runaway global heating, even as they acknowledge many of the knock-on risks aren’t fully known. “Until recently, I thought it was too risky, but slow progress on cutting emissions has increased motivation to understand techniques at the margins like solar geoengineering,” said Chris Field, who chaired a National Academies of Sciences report last year that recommended at least $100m being spent researching the issue.

“I don’t think we should deploy it yet and there are still a ton of concerns, but we need to better understand it,” Field said. “Climate change is causing widespread impacts, it’s costing lives and wrecking economies. We are in a tough position; we are running out of time, so it’s important we know more.” [Continue reading…]