Workers plant sacsaoul trees at Ulan Buh Desert in Dengkou County of Bayannur City, north China’s Inner Mongolia Autonomous Region, March 25, 2018. Work is in progress to green the desert in Bayannur by planting trees such as sacsaouls and desert grapes. Photo:Xinhua

A few euros, a couple of mouse clicks and a tree is planted – as air travel is increasingly becoming a source of guilt, consumers and companies are looking for other ways to ease their conscience and reduce their carbon footprint. 

But as more polluting industries join efforts to offset their carbon emissions, the effectiveness of the approach is open to debate, with some critics suggesting that tree-planting schemes are nothing more than a fig leaf.

Once marginal, the offset movement has even reached the archenemy of environmentalists: big oil.

British-Dutch oil and gas company Shell has ploughed $300 million into forest plantations to reduce its carbon footprint by 2-3 percent, Italy’s ENI has set an objective of zero net emissions via its forestry investments, and France’s Total plans to set up a special “business unit” next year to spend $100 million annually on compensation efforts.

Beyond the grand statements, carbon offset schemes basically follow the same, simple mechanism.

A polluting company or individual purchases a credit equivalent to a ton of carbon dioxide and the purchase price is paid directly or indirectly into an emissions reduction scheme, such as planting trees which absorb CO2 responsible for global warming or investment in renewable energy sources. 

This is the principle that the civil aviation industry is adopting with its initiative Carbon Offsetting and Reduction Scheme for International Aviation starting from 2020. Sixty-five countries have signed up to it so far – equivalent to 87 percent of all international activity in the sector. 

“There will be a number of eligible carbon reduction schemes and airlines will be able to buy the equivalent tons of CO2 via these projects,” says Nathalie Simmenauer, Air France’s head of environment and sustainable development. 

The aim is to reach “neutral carbon growth” – that is to ensure future emissions are held at 2020 levels. 

While trees are an important tool for regulating the climate, reforestation alone cannot whitewash a company’s carbon-emitting activity, say activists. 

“If you don’t reduce your emissions and don’t stop deforestation, you’re not going to solve anything by merely planting trees,” says Stephane Hallaire, president and founder of Reforest’Action, which has planted 3.8 million trees in nine years. 

But Hallaire argues that reforestation must also be accompanied by better behavior elsewhere.