Prince Harry and Meghan Markle have found themselves in the middle of an environmental row after it emerged that they made four trips in private jets in 11 days – all whilst campaigning for action on climate change.
Sir Elton John, who organised two of the flights to and from his Nice home to provide the Royals with a "high level of much-needed protection", said he "ensured their flight was carbon neutral, by making the appropriate contribution" a carbon offset scheme.
However, Greenpeace scientist Doug Parr hit out at Sir Elton on Twitter, stating: “Carbon offsetting is not a meaningful response to aviation emissions."
Adding that while "good works" can be done by paying to offset carbon emissions, "it is no solution".
With celebrities from Sir Elton to Coldplay endorsing and investing in carbon offsetting schemes, does it actually work, or it is it just a way for people to clear polluted consciences?
What is carbon offsetting?
Carbon offsetting is simply a form of trade.
When someone does something that increases their carbon footprint, for example flying on an aeroplane, they can fund projects to reduce greenhouse gas emissions elsewhere.
Planting trees is one such example, since trees absorb carbon dioxide which is released into the atmosphere.
Many organisations offer many other schemes, from forest restoration, to providing renewable energy to third world countries.
For example, Pink Floyd donated proceeds from their 2001 Echoes album to rejuvenating four indigenous forests.
In essence, you are attempting to pay off your own carbon footprint.
How can you offset your carbon footprint?
First of all, you should calculate your carbon footprint.
The UN Carbon Offset calculator allows you to figure out your household’s carbon footprint, based on gas and electricity usage, the amount of food you consume and how much travelling you do.
It will then give you options on how you can offset your carbon footprint.
Depending on the project, it could cost as little as £1 to offset one metric tonne.
According to British Gas, the average carbon footprint of a UK citizen is 5.99 metric tonnes per year.
Does carbon offsetting actually work?
Yes and no.
Areeba Hamid, Climate Campaigner for Greenpeace UK, told ITV News that while carbon offsetting is an admirable cause, it is not a get-out-of-jail-free card.
“The worst thing about offsetting, the thing that can make it worse than nothing, is the mistaken belief that it makes polluting activities environmentally friendly,” she said.
“If you cut your emissions as much as you can, then offsetting the rest is a good thing.
“If you increase your emissions because you think offsetting makes that OK, then the offset scheme is actually damaging the environment.”
She adds that it can get complicated, as money put towards some schemes may not actually go anywhere.
“As an example, if you emit a tonne of carbon, and then pay someone to plant trees to soak up that carbon, do you know for sure they will plant them, and that they wouldn’t have planted them otherwise?
"Do you know how long the trees will take to soak up the carbon you have emitted?” she asked.
As there are so many carbon offsetting schemes available, non-profit The Climate Group have offered advice on how people can choose carbon offset schemes wisely.
What’s a better solution?
Everyone can do their part to decrease their carbon footprint, whether it be by using less electricity or walking to work.
In the case of Harry and Meghan, it's possible they could have taken a leaf out of the Cambridges’ book, who were snapped boarding an economy flight to Scotland on Thursday.
Clive Jackson charters private planes for the rich and powerful, he told ITV News a private jet flight emits 20 times as much carbon dioxide as a normal one.
However, there is only so much one person can do.
Ms Hamid admits significant changes will only happen if the government takes action.
“Cutting your own emissions by insulating more, flying less or eating less meat are all good things, but we need big changes from big corporations, and particularly from governments, and the most important thing you can do is to put whatever pressure you can on them,” she said.