While touting itself as “Europe’s Greenest Airline”, budget carrier Ryanair has become the first company that doesn’t run a coal-fired power plant to break into the top-10 list of European climate polluters, prompting a headline writer at Grist to nominate the company for membership in the “mile high emissions club”.

The analysis comes from Brussels-based Transport & Environment, which reported last week that Ryanair’s carbon dioxide emissions rose 6.9% in 2018 and 49% over the last five years. Total measured emissions across the EU Emissions Trading System (ETS) fell 3.8% last year.

“The findings underscore the airline industry’s rising contribution to greenhouse gases blamed for damaging the climate,” Bloomberg reports. “Pollution from airlines has risen by about two-thirds since 2005 and is forecast to keep rising as flying becomes more affordable. That puts the industry on course to become the single-biggest emitter within three decades.”

“The Irish airline has its frequent flier customers to thank for its climb to carbon-emitting fame,” Grist notes. “Since its founding in 1984, Ryanair has worked hard to keep its costs as low as possible. This means US$12 tickets from Dublin to Amsterdam, but it also includes hiring contract pilots, flying to secondary rather than main airports, and hidden fees, like charging for a second carry-on. Despite all this, Ryanair has quickly become the largest European airline, with more than 2,400 flights daily.”

In a statement, Ryanair maintained its passengers still “have the lowest CO2 emissions per kilometre traveled than any other airline.”

Within the ETS, the cap-and-trade system the EU uses to monitor and decrease carbon emissions, “aviation companies are privy to a large amount of untaxed emissions,” Grist notes. “So Ryanair and other airlines have been able to increase their carbon emissions dramatically over the past couple of  years with few economic consequences. Without any policy changes, EU airline carbon emissions are expected to grow 300% by 2050.”

That prompted University of Manchester energy and climate change professor Kevin Anderson to tell The Guardian: “If we genuinely care for our children’s futures, we need to drive down the demand for aviation. This will require stringent regulations focusing on frequent fliers, rather than those taking the occasional trip.”