A new report claims the increase in passenger numbers expected at Leeds Bradford Airport after its £150 million overhaul could create carbon emissions six times higher than first thought.
Plans for a new £150m terminal at the airport in north Leeds are currently on hold as government analyses the proposals.
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However, airport chiefs say an expansion of passenger numbers to seven million a year has already been granted under a separate application.
The new terminal has been met with strong opposition. Climate campaigners are now pointing to a report from the New Economics Foundation (NEF) to try to stop the multi-million pound plans.
It claims that annual carbon emissions at Leeds Bradford Airport could reach 787,000 tonnes of CO2 and CO2-equivalent in 2035 - the same amount as pollutants from 430,000 cars.
When combined with the planned expansions of Bristol, Southampton and Stansted airports, the NEF say the airports have ignored up to £13.4 billion worth of combined potential damage to the climate in the form of high altitude pollutants such as carbon dioxide, aerosols, nitrogen oxides and water vapour.
"The Secretary of State should call in all of the currently active airport planning applications and assemble a more robust and precautionary evidence base on climate change issues," says the report, titled Turbulence Expected, The Climate Cost of Airport Expansion.
"In addition, the government will need to demonstrate how the proposed expansions can be reconciled with the Climate Change Committee’s recommendation of a nonet-expansion policy on airports."
The new terminal at Leeds Bradford Airport was initially granted planning permission by Leeds City Council earlier this year, but it has since been temporarily halted.
Communities Secretary Robert Jenrick is poring over the plans and could even order a public inquiry into the huge development.
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However, airport bosses have repeatedly stressed that the new terminal itself will be built to the most rigorous environmental standards.
Speaking at the Leeds City Council meeting in February, Leeds Bradford Airport chairman Andy Clarke said: "It will lead the way for the UK aviation sector to decarbonise.
"This is a clear signal that Leeds Bradford Airport wants to be innovative and show leadership for change in Yorkshire, attract airlines with the most environmentally-friendly aircraft and to pave the way for a sustainable future. A modern city with a modern airport."
