We terrestrials spend a lot of our breath sequestering carbon in the atmosphere If we put aside our earthly bias, ocean is the world's largest carbon sink — on the order of ~50 times more carbon than is currently in the atmosphere. But wringing out nature’s sequestration sponge is no small feat. The field of ocean-based carbon dioxide removal (CDR) is nascent, complicated, and risky—even compared to the complex carbon removal technology on land. Yet we’ve made such a mess on Aisle Earth that it is now necessary Mop vigorously with all possible carbon sponges Companies backed by businesses like Running Tide , Ebb Carbon a Brilliant Planet are already working on solutions to accelerate ocean CO2 uptake, but the science is far from settled. On such a large scale and open system, it is difficult to predict the ripple effects caused by modifying the chemistry or biology of marine ecosystems for accelerated carbon sequestration. Just measuring the efficiency and durability of carbon removal remains a huge challenge, given that the oceans cover ~70 % of the planet with constantly changing currents. Researchers and entrepreneurs working on the ocean CDR frontier must navigate a turbulent current of challenges, from regulatory and technical hurdles to equity concerns. Indeed, these knowledge and policy gaps must be addressed before many potential ocean CDR business models can be commercially viable, and certainly before these climate technologies can be scaled up responsibly. (Climate Tech VC)