It’s currently popular to argue for fighting climate change by “solar geoengineering”—such as sending sulfates toward the sun to cool the Earth’s surface (the way a volcano’s eruption can cool the Earth). But many people question this approach.
The latest warning comes from Robinson Meyer in the Atlantic.
“A new study hints that solar geoengineering is going to be even more complicated than its proponents realize: It could expose tens or even hundreds of millions of people to malaria every year. “
Malaria breeding increases as temperatures get warmer. However, after a certain temperature (93 degrees F), says Meyer, mosquitoes lose their metabolic speed and begin to weaken.
“[A]s the temperature keeps rising, mosquitoes become less and less able to function, and at about 34 degrees Celsius, or 93 degrees Fahrenheit, they start ‘dropping out of the air.’ That means there is a hard thermal peak to mosquito survival and, with it, malaria transmission.”
Depending on how much warming has occurred, geoengineering could increase malaria by dropping the temperature to a level more suited to mosquito proliferation.
“In an extreme, worst-case scenario, in which humanity raises global temperatures by several degrees by 2070 before trying to bring them back to a 2020 level, geoengineering could put perhaps 1 billion people at an increased risk of malaria.”
And then there is Roger Pielke, Jr. of the University of Colorado Boulder, with broader objections.
“Solar engineering would have effects on the climate system through direct and indirect radiative forcing, non-radiative forcings, and various feedbacks among these. Fully characterizing these effects, much less demonstrating accurate and reliable predictions of the consequences of solar engineering deployment, necessarily is theoretical.”