changes to jet fuel could mitigate climate impacts. PHOTO BY BOB BERWYN.
Taking sulfur out of jet fuel could cut global warming impacts of aviation
By Summit Voice
SUMMIT COUNTY — At about 31 million flights per year, aviation is the fastest-growing fossil fuel-burning sector in today’s global economy, and emissions are expected to increase significantly in the next few decades, while other sectors decrease.
As a result, researchers have been focused on assessing the impact of aviation emissions on climate, and in a recent Yale University study, they found that removing sulfur from jet fuel cools the atmosphere.
Particles of sulfate, formed by burning sulfur-laden jet fuel, act like tiny mirrors that scatter solar radiation back into space. When sulfur is removed from the fuel, warming occurs but it’s offset by the cooling effect of nitrate that forms from nitrogen oxides in jet exhaust. The result is that desulfurization of jet fuel has a small, net cooling effect.
“It’s a win-win situation, because the sulfate can be taken out of the fuel to improve air quality around airports and, at the same time, it’s not going to have a detrimental impact on global warming,” said Nadine Unger, an assistant professor of climate science at the Yale School of Forestry & Environmental Studies.
In 2006 the United States introduced an ultra-low sulfur standard for highway diesel, and the Federal Aviation Administration (FAA) is interested in de-sulfurized jet fuel for its potential to improve air quality around airports.
Aircraft exhaust particles lodge in the lungs and cause respiratory and cardiovascular illness. In 2006 there were more than 31 million flights across the globe, according to an FAA emissions inventory.
Unger used a global-scale model that assessed the impact of reducing the amount of sulfur in jet fuel from 600 milligrams per kilogram of fuel to 15 milligrams per kilogram, which is the level targeted by …