The oceans and coasts are the Earth’s climate regulators. Covering 72 percent of the planet’s surface, they have absorbed about 40 percent of carbon emitted by human activities since 1850.1 Coastal ecosystems such as mangroves, tidal marshes, and seagrass meadows act as deep carbon reservoirs, while marine ecosystems and fauna absorb and sequester greenhouse gases (GHG) through the carbon cycle.2 However, over recent decades, both oceans and coasts have come under pressure from atmospheric and marine warming, habitat destruction, pollution, and the impacts of overfishing and industrial activity. These destructive factors undermine the effect of oceanic systems in reducing atmospheric carbon.