Making Flying Cleaner

I spoke to Tyler Lark, a scientist at the University of Wisconsin-Madison whose 2022 study questioned ethanol’s climate credentials and concluded that it can be more carbon-intensive than gasoline. He told me that the margins on ethanol’s benefits are thin enough that, depending on the model you chose to calculate its effects, the results can be radically different. His paper prompted rebuttals from the Renewable Fuel Association, an industry group, and the United States Department of Agriculture.