NB: See:
https://www.sciencedirect.com/science/article/pii/S1352231020305689#bht.fefb08c5-407f-4b9f-8267-ccc0b6f20537.7
for the actual research journal article upon which the popular press
item (below) is based.
I attempted to attach the PDF of the article to this posting, but the
size of the article exceeded the message size allowed by the service
being used, even when I zip compressed the PDF file.
https://news.yahoo.com/contrails-aviations-biggest-threat-environment-233000313.html
Jalopnik
How Contrails Are Aviation's Biggest Threat to the Environment
Ryan Erik King
Fri, January 13, 2023 at 3:30 PM PST
These clouds are slowing killing us. No, I’m not wearing a tinfoil hat.
It would be easy to assume that the commercial aviation industry’s fuel
consumption was its biggest impact on the environment. For example, a
Boeing 737-800 burns about 5,000 pounds of fuel an hour in the sky.
However, research shows that persistent contrails play a much larger
role. An eight-year-long study found that contrails created 57 percent
of the industry’s contribution to the climate crisis.
Contrails are the thin wispy clouds created by jet engine exhausts.
Water vapor condenses into ice crystals around particulates blown out
the back of the turbines. The vast majority of the time, contrails
dissipate within minutes. Ten percent of the time, contrails remain
intact. These persistent contrails trap heat in the atmosphere that
would otherwise radiate into space, directly contributing to the
increase in global temperature.
Last year, Etihad Airways became the first passenger airline to use
contrail-mitigating routing software as a part of its Greenliner
sustainability testing program. Satavia, the software’s developer, was
initially established to increase the longevity of jet turbine engines
by routing to avoid particulates in the skies, like volcanic ash.
Though, the company realized its efforts could have a cost-effective
impact on the environment for increasingly climate-conscious airlines.
Satavia’s founder, Adam Durant, told CNN:
“The airlines go ahead and make flight plans as they normally do.
But in parallel to that, we analyze their schedule and look at a number
of flow trajectories for every single flight. We end up with a long list
of flights of which the top 5% or so have these heavy hitter, long-lived
warming contrails. And then we work closely with the flight ops
department in the airline to target those.”
Only a few routes would have to be adjusted to eliminate nearly all
contrails. Satavia hopes to scale up its operations and is slated to
begin another test with KLM. Other groups have realized the potential
impact of eliminating contrails. Delta and MIT are collaborating on an
open-source routing algorithm to mitigate contrail formation.
