Removing Contrails Could Reduce Global Warming Impact

Good news to everyone who flies, but doesn’t like the aviation industries impact on climate change and global warming.  It looks like a small change in flight altitude can greatly reduce the impact on trapping heat within the atmosphere.  They talk about a 59% reduction if only 2% of the flights globally fly at a different altitude.  That is a HUGE potential impact, with only a very small addition in fuel costs.

Greener fuels, electric engines and more efficient aircraft are all being touted as ways to reduce the environmental harm of flying, but a new study suggests one simple move could help existing flights drastically cut their impact.

By changing the flying altitude by just couple of thousand feet on fewer than 2% of all scheduled flights, a study by a team of scientists at Imperial College London concludes that aviation’s damage to the climate could be reduced by as much as 59%.

It’s all about eradicating airplane contrails — those white streaks you see criss-crossing the skies after an airplane has passed overhead.

Contrails, says NASA, are “a type of ice cloud formed by aircraft as water vapor condenses around small dust particles, which provide the vapor with sufficient energy to freeze.”

These cloud-like formations can have a cooling effect, acting to reflect sunlight that would otherwise heat the Earth. Contrails can also block outgoing heat from escaping the earth — essentially acting like a blanket, trapping heat.

In November 2019, a study by a group of MIT scientists concluded contrails account for 14% of climate and air quality damages per unit aviation fuel burn.

The big difference between C02 emissions produced by an aircraft and contrails, however, is that contrails don’t last very long, a maximum of about 18 hours.

“So if we were to stop producing contrails, the effect of contrails would go away the next day,” says Marc Stettler, who worked on the new study. “It’s a way that the aviation industry can really quickly address its impact on climate change.”

Flying an airplane higher or lower could help get rid of contrails because they only form in thinner areas of atmosphere, with high humidity — so it’s theoretically possible to avoid them and reap the eco-benefits.

You can read the full article here.