Solar geoengineering is a radical idea that has been gaining traction among some scientists and policymakers as a possible way to combat climate change. The idea is to artificially reflect some of the sun’s rays back into space, thereby cooling the planet and offsetting some of the effects of greenhouse gas emissions.
But solar geoengineering is also fraught with risks, uncertainties, and ethical dilemmas. How would it affect rainfall patterns, ecosystems, and human societies? Who would decide when and how to deploy it? What if it goes wrong or is stopped abruptly?
To answer these questions, researchers need more data and better models. That’s where a new supercomputer comes in. Named Derecho, the machine is funded by the federal government and operated by the National Center for Atmospheric Research (NCAR). It will allow scientists to run more detailed weather models for research on solar geoengineering, especially on how human-made aerosols, which can be used to deflect sunlight, could affect thunderstorms and precipitation.
“To understand specific impacts on thunderstorms, we require the use of very high-resolution models that can be run for many, many years,” said Kristen Rasmussen, a climate scientist at Colorado State University who is studying how aerosols could affect rainfall patterns. “This faster supercomputer will enable more simulations at longer time frames and at higher resolution than we can currently support.”
Derecho, which is Spanish for “straight line,” is 3 ½ times faster than the previous NCAR supercomputer. It can perform 19.87 quadrillion calculations per second, making it one of the most powerful computers in the world for Earth system science. It will also be used to study other issues related to climate change, such as sea level rise, wildfires, and hurricanes.
The announcement from NCAR comes after the Biden administration released a report last week that offered measured support for researching solar geoengineering as a way to slow the rise of global temperatures. The report follows an open letter by more than 60 leading scientists calling for more research into solar geoengineering. European Union policymakers also issued a statement last week calling for an international assessment of the risks related to geoengineering.
“These technologies introduce new risks to people and ecosystems, while they could also increase power imbalances between nations, spark conflicts and raises a myriad of ethical, legal, governance and political issues,” the E.U. statement said.
Critics of geoengineering say using aerosols and other substances to reflect sunlight away from Earth could lead to unknown, disruptive weather patterns. They also contend that solar geoengineering could result in a global dependency, because temperatures could abruptly rise if the process is stopped.
The Union of Concerned Scientists opposes the deployment of solar geoengineering because it poses unacceptably high environmental, social, and geopolitical risks. Instead, UCS supports continued modeling research, observational studies, and strong, inclusive public participation in decision-making over whether and how further research should include possible small-scale outdoor experiments.
Solar geoengineering is not a substitute for reducing greenhouse gas emissions or removing carbon dioxide from the atmosphere, but rather a potential supplement that would require careful consideration and public participation.
Relevant articles:
– Supercomputer Will Help Decide whether to Block the Sun, Scientific American, July 7, 2023
– Solar geoengineering could limit global warming, but Canada should study risks and benefits first, The Conversation, July 8, 2023
– 1 big pro and 4 cons of solar geoengineering, Inverse, July 9, 2023
– The Planet-wide Problem That Is Solar Geoengineering, Discover Magazine, July 10, 2023
As runaway climate change seems more and more likely, geoengineering is getting a closer look. But there is little coverage of MEER, which is a GE method using surface based mirrors. Its advantage over other methods is simplicity, scalability and effectiveness. Please look into this and publish your take on the science. Their web site contains exhaustive detail, both for the layperson and the scientist. They are at MEER.ORG . . . Thanks.