Blue carbon, a way to remove greenhouse gases from which some countries benefit

Published on :

Blue carbon, carbon released and stored by plants on the coasts, is increasingly presented as one of the solutions to global warming. It is a means of removing some of the greenhouse gases emitted by man from the atmosphere. But here it is, a new scientific study published in the journal Climate frontiers shows that this effect tends to be overestimated by certain countries which could then take advantage of it to emit more than they should.

Restoring marine ecosystems so that they absorb and then store carbon is like planting trees, except this time it’s happening by the sea. The idea is attractive, also interesting for States and companies because in exchange, they can receive carbon credits which enable them to emit more.

But now, these credits can be much higher than the benefit offered, with all the harmful effects that this implies for the fight against global warming. ” Carbon credits must be in proportion to the carbon that has been stored, and this carbon that has been stored, in the short term, we have great difficulty in estimating it, explains Jean-Pierre Gattuso, CNRS researcher at the Villefranche-sur-Mer oceanography laboratory and one of the authors of the study. For example, on salt marshes there may be a difference in CO2 uptake by a factor of 100 to 500, an uncertainty that is very large. »

► To read also: Earth Overshoot Day: Humanity has consumed all the planet can produce in one year

Ecosystems to protect

Jean-Pierre Gattuso insists, however, that mangroves, salt meadows and others should not be neglected: “ These blue carbon ecosystems are not just CO2 sinks, they provide enormous services to human communities for shoreline protection, for food security, for maintaining biodiversity, so there are lots of good reasons to restore these ecosystems, but we must not think that we are going to derive a climate benefit from it. »

These ecosystems must therefore be protected even though they are currently threatened. Mangroves, for example, are constantly shrinking in area, eaten up by other uses such as aquaculture.


Leave a Comment