United Nations organization adopts goal of net-zero emissions from planes by 2050

A United Nations organization on Friday adopted a "long-term aspirational goal" of making carbon emissions from air travel net zero by 2050 in response to growing pressure for airlines to reduce their pollution. Several major environmental groups praised the move, saying it could boost the production of sustainable aviation fuel. But they cautioned that it will be difficult to push countries to follow up with policies that actually reduce emissions.

Aviation is a relatively small contributor to overall climate-changing emissions, but its share is expected to grow. More people are expected to travel on planes in the coming years, and aviation lacks cleaner alternatives such as electric power that are widely available for cars and trucks.

Friday's decision in Montreal occurred during a meeting attended by representatives of nearly 200 nations that belong to the UN's International Civil Aviation Organization, or ICAO.

The decision capped nearly a decade of negotiations and occurred as aviation comes under more pressure to help meet conditions of the 2015 Paris Agreement on climate, which aims to cap the rise in global temperature. Crucially, the ICAO agreement does not set targets for individual countries or airlines.

Mark Brownstein, a senior official at the Environmental Defense Fund, said the resolution raised hope that travel will be more sustainable. "But the work isn't over," he said. "Now is the time for countries to act by establishing policies that support achievement of a 2050 net-zero goal for aviation with measurable progress in the interim."

Dan Rutherford, who tracks the issue for the International Council on Clean Transportation, said that to hit the net-zero target, aviation emissions will need to peak and start decreasing as soon as 2025, "with richer countries taking the lead."

Environmentalists said reaching net zero will require greater use of so-called sustainable aviation fuel that is not made from fossil fuels because large electric- or hydrogen-powered planes are decades away.