An environmentalist couple have not flown in an aeroplane for nearly 20 years because they want to protect the Earth “for your grandchildren”.

Catherine Budgett-Meakin, 67, and her husband John Mead, 88, of Highgate, have only flown seven or eight times in the 35 years they have been married. But they decided to cut out all flights in 1996, at a time when they grew more aware of ways to lead a reduced carbon lifestyle.

They are just two of a dedicated number of green-minded individuals who say that air travel is antithetical to environmentalism.

One flight produces more carbon emissions than a journey taken by any other means of transport.

Bisham Gardens resident Ms Budgett-Meakin, co-founder of the Population and Sustainability Network, which brings together environmental organisations, said: “There is an assumption that we are entitled to fly for our holidays, but this is not an entitlement.”

Mr Mead, who has worked as a lecturer and psychotherapist, added that they chose to stop taking flights because they want to be actively involved in stopping the Earth’s “climate catastrophe”.

“We want to protect the Earth for your children and your grandchildren,” he said. “If you care about what happens to your grandchildren, you would do well not to fly.”

Before they stopped flying altogether, they always tried to reduce carbon emissions when travelling by taking bicycles with them and using public transport.

Their decision to cut out flights has not hampered their holiday plans and they choose to take breaks in France or the Isle of Wight instead of further afield.

The furthest they have travelled without taking an aeroplane is Sicily. But for many, even those with a green conscious, the allure of being able to visit far-flung places at low prices makes the decision to cut out, or reduce, air travel very difficult.

Those in long-distance relationships or who have to travel for business may also find it nearly impossible to give it up entirely.

Ms Budgett-Meakin said: “It is relatively cheap whereas going by train is more expensive, and that is awful. If aeroplanes were forced to pay the proper environmental cost, then it would be more expensive. But it is tricky because that would put travel out of reach for many.”

For researcher Mayer Hillman, of Netherhall Gardens, Hampstead, the choice to cut out air travel was made after he realised it would be hypocritical of him to fly when his work is centred around environmentalism.

Mr Hillman, who designed the Ham&High’s former offices in Perrin’s Court, Hampstead, in the 1960s before changing careers, has not flown in 17 years.

The senior fellow emeritus at Policy Studies Institute in Marylebone said: “I realise it is a pathetic gesture and that it is not going to stop climate change, but I feel that it is important.

“Much of my research focuses on climate change so I don’t want to be classed as a hypocrite.”