Key Points:

  • Airplane contrails contribute significantly to global warming, trapping heat in the Earth's atmosphere.

  • Breakthrough Energy and Google have collaborated to develop machine-learning models to predict and reduce contrail formation.

  • Pilot tests with American Airlines show contrail creation reduced by 54%, though challenges like increased fuel usage persist.


Breakthrough Energy and Google Combine Efforts for Contrail Control


FORT WORTH —Though aviation’s contribution to global warming is largely attributed to fuel emissions—making up approximately 3.5% of human-caused global warming—a significant culprit also lies in the sky: contrails. These artificial cloud-like formations, composed of ice crystals, surround particles from plane exhaust, thereby trapping heat within our planet's atmosphere.

Researchers at Breakthrough Energy, alongside Google, assert that contrail reduction presents a significant, yet achievable, opportunity to counter global warming. In the words of Marc Shapiro, contrail chief at Breakthrough Energy, this is the “highest-leverage climate opportunity we're aware of," potentially allowing atmospheric carbon removal at less than 10 dollars per ton.

Delving back in history, the genesis of contrail studies lies in the 1940s for military purposes. However, by the 1990s, a link was drawn between cirrus clouds, which are akin to contrails and can be induced by them, and atmospheric heating. Last year, the Intergovernmental Panel on Climate Change (IPCC) stated that contrails constitute roughly 35% of the aviation sector’s global warming impact.

The potential remedy? Utilizing satellite data, bolstered by machine learning, to enable planes to steer clear of creating contrails. The primary challenge is evading atmospheric regions abundant in ice supersaturated humidity where long-enduring contrails manifest. Such adjustments often mirror altitude alterations that pilots employ to dodge turbulence zones.

Both Breakthrough Energy and Google have separately crafted models to foresee contrail formation. In 2022, their united endeavor commenced. Juliet Rothenburg, heading Google’s venture into climate change and artificial intelligence, highlighted the challenges in humidity predictions. Their solution leveraged data from NASA’s GOES-16 weather satellite and other meteorological indicators, trained to spot and forecast contrail-prone regions.

To empirically test their findings, a partnership with American Airlines was forged. Pilots, over 70 flights from January to March 2023, utilized both regular and altered routes. Subsequent satellite data analyses revealed a promising 54% reduction in contrail generation. Jill Blickstein, VP of sustainability at American, envisions this becoming an industry standard in the foreseeable future.

However, challenges persist. For instance, American’s increased fuel consumption by 2% due to additional maneuvers. Blickstein acknowledges this meaningful increment and underscores the need to ensure that contrail reduction benefits surpass the added emissions.

As the research advances, both Breakthrough and Google envisage its commercial deployment. While both view their work as reinforcing their carbon reduction pledges, Rothenburg anticipates improved precision with future higher-resolution satellites. Furthermore, Breakthrough aspires to spearhead an autonomous body to gather and verify contrail data, aiming for it to evolve into a global airline-supported clearinghouse.

In Blickstein's words, even a rough estimate has profound potential. The path forward? Simply guiding planes to the right atmospheric locations could decrease human-induced global warming by about 1%.