Prince Harry wants us to do it. Emma Thompson does, too. And unlike the other two, who've been criticized for their high-carbon lifestyles at odds with their public pronouncements, Greta Thunberg actually does it herself.
"Greening" our vacations -- making travel more sustainable without relinquishing it entirely -- is one of the fastest growing movements in travel.
Earlier this year, the Swedish term flygskam, or "flight-shaming," was judged responsible for an 8% rise in rail journeys in the country, as travelers became more aware of the environmental impact of their movements and swapped internal flights for train travel.
It's not just air miles that have a carbon footprint. A 2018 report by journal Nature Climate Change found that tourism accounts for about 8% of global greenhouse gas emissions, and that shopping and food are "significant" contributors.
But while many are pledging to give up flying entirely, others are wanting to make their trips more sustainable -- not just in terms of how they get there, but how they pick their destination in the first place and what they do on the ground.
A survey in 2018 by Hilton hotels found that a third of travelers actively seek out information on environmental initiatives before making a reservation. And as awareness of the climate crisis expands, that number can only be set to grow.
Of course, while refraining from flying saves significantly on carbon emissions, local communities around the world rely on tourism to survive.
"Tourism absolutely helps contribute to a sustainable local economy," says Gregory Miller, executive director at the Center for Responsible Travel (CREST). "We just don't want to visit places to death."
So how do you make your travel greener?
Before you go... Adjust your travel patterns
Justin Francis, CEO of Responsible Travel -- a tour operator which only sells sustainable holidays -- says the choice is stark.
"The only way we can reduce our amount of carbon emissions is to fly less," he says. Francis rejects the idea of carbon offsetting schemes -- a 2017 European Commission study found that 85% of such schemes do not work.
Instead, he says, we need to change our travel habits.
"When I was growing up, people tended to take one longer holiday a year, of about two weeks, plus a domestic trip, and maybe one more.
"With the advent of low-cost aviation, many of us are taking multiple flights, and holidays are much shorter.
"If we went back to the style of travel we used to enjoy, we'd achieve the reduction in flights that we need."