The 189 club cars north of the Border have reduced the number of privately owned vehicles by 2,750 as members sell their car or defer buying one, car-sharing group Carplus said.
The survey also found car club vehicles had 30 per cent lower carbon emissions than the average car.
Carplus said more than nine in ten vehicles had the best available technology for limiting pollutants such as nitrogen oxide and particulate matter.
Edinburgh’s City Car Club is Scotland’s oldest and largest –and the biggest outside London with 114 vehicles. Aberdeen is next among Scotland’s 16 clubs, with 24 cars, followed by Glasgow, with 21.
Matthew Eastwood, car club development manager (Scotland) for Carplus, said: “Car clubs reduce the number of cars on Scotland’s roads and offer access to less polluting vehicles and electric vehicles.”
Environmental groups welcomed the survey results, but motoring groups were sceptical about the benefits of clubs.
WWF Scotland director Lang Banks said: “If Scotland is to get back on track toward meeting its climate change targets, then it needs to seriously curb emissions from cars.
“It’s clear from these findings that car clubs not only help people to avoid carbon pollution but also help to reduce harmful, health-damaging air pollution too. It would be great to see similar schemes in every large town across Scotland.”
Colin Howden, director of green transport campaigners Transform Scotland, said: “There is great potential for growth in sharing schemes, both car-sharing and bike-sharing, and local authorities and regional transport partnerships need to work proactively with the private sector in further establishing sharing schemes across Scotland.
“It is also a sector in which the Scottish Government should significantly increase its investment.”
But Edmund King, president of the Automobile Association, the UK’s biggest motoring group, said: “In our experience, car clubs and car sharing often attract people who would otherwise use public transport rather than people who own cars and give them up. Hence some of the environmental claims for car clubs seem pretty far-fetched.”
Mr King said that all new cars were getting cleaner and greener and that, due to the relative cost of fuel, “some 60 per cent of AA members are cutting back on journeys but not actually giving up their cars”.
Neil Greig, the Scotland-based policy and research director of the Institute of Advanced Motorists, said: “It is a big leap to say 189 shared cars are making a huge difference to air quality when we have 2.4 million cars on Scotland’s roads, but every little helps.”
Transport minister Keith Brown said the Scottish Government had provided funding for the Developing Car Clubs programme in Scotland since 2010.