A day after ratifying the Paris climate change accord, Canada has signed on to the first global agreement to tackle pollution in the airline industry.

Transport Minister Marc Garneau called it a "historic agreement," but some critics say it won't do enough to help fight global warming.

Garneau said Canada played a leading role in the backrooms at the Montreal-based International Civil Aviation Organization (ICAO) to bring as many countries as possible on board, and 85 per cent of the world's emitters will participate in a voluntary carbon-offset system beginning in 2021.

Even though civil aviation and international flights will continue to increase, they will be carbon neutral beyond 2020 under the agreement with a market-based measure that requires airlines to buy carbon credits.

It's the first global carbon offset system for a single industry.

Airlines onside

Garneau said Canadian airlines are onside with the plan, which could lead to an increase in airfares of one to 1.5 per cent.

"Canadian aviation companies, airlines, are prepared to sign up to this, the global market-based measures. I believe that air travellers are also," he said.

Transport Minister Marc Garneau discusses a new global agreement for airlines to become carbon neutral by 2021. 2:26

The system will be voluntary from 2021 to 2026 and become mandatory for most countries beginning in 2027.

Aviation was excluded from the Paris climate agreement, which passed the threshold for ratification on Wednesday. The accord will go into force Nov. 4, with Canada among the 191 signatories.

Michael Gill, the executive director of the Air Transport Action Group, called it a "historic moment" for aviation and climate negotiations.

"What was a visionary approach seven years ago has today become a reality," he said in a statement.

'Worrying signal'

But some disappointed environmental groups say the agreement doesn't go far enough.

"In the same week that the Paris agreement crosses its crucial threshold to enter into force, countries sent a worrying signal by deleting key provisions for the aviation agreement that would align its ambitions with the Paris agreement's aim of limiting global temperature rise to well below two degrees with best efforts to not exceed 1.5 degrees Celsius," reads a statement from the International Coalition for Sustainable Aviation.