Blue Carbon: The Potential of Oceanic Climate Action

According to Mckinsey's report,

"Humankind’s impact on coastal and offshore ecosystems is a double-edged sword. While we are responsible for significant destruction, we also have agency over potential outcomes. Through our efforts, we can avert damage to or even restore ocean ecosystems, removing carbon from the atmosphere and moving the world toward net-zero emissions, as envisaged by the Paris Agreement on climate change.

Here we consider three categories of blue-carbon solutions, classified by their scientific and economic maturity.

Established solutions

Focused on mangroves, salt marshes, and seagrass meadows, these solutions are widely understood, offer scientifically verifiable levels of carbon abatement, and are amenable to funding through established approaches, such as the purchase of carbon credits.

Emerging solutions

This category includes the protection and restoration of seaweed forests, the extension of seaweed forests, and strategies to reduce bottom trawling. These solutions have undergone initial peer-reviewed research to quantify their potential to abate CO2, but significant scientific uncertainty still needs to be addressed. Given this uncertainty, and the fact that practical solutions are not sufficiently mature, solutions in this category cannot yet be financed through carbon markets.

Nascent solutions

This potentially powerful group of solutions is mainly focused on protecting and restoring marine fauna, from oysters to whales. These solutions involve challenges such as quantifying their impact, establishing permanence, preventing leakage, and proving additionality— that is, proving that without the solution a particular benefit would not have happened.

For each category of solutions, this report sizes approaches and measures their impacts, costs, and likely access to funding. It highlights the latest scientific research and leverages McKinsey analysis to estimate the potential for abatement or conservation by 2050. This report also includes deeper analysis of kelp reforestation and bottom trawling to show how economies of scale in these emerging solutions could help reduce prohibitive costs."