NZ scientists study ocean carbon removal: alkalinity, biomass, and phytoplankton blooms

New Zealand scientists have launched a five-year research program to test ocean-based carbon removal techniques. The first voyage studied natural alkalinity from rivers and sediments in Hawke's Bay, which could inform methods to enhance the ocean's carbon uptake. The ocean already absorbs about a third of human CO2 emissions, and researchers want to measure how much additional carbon these techniques could sequester. Future voyages will examine how terrestrial biomass like trees washed into the ocean during Cyclone Gabrielle degrade, and how natural phytoplankton blooms lock away carbon. The goal is to create a verification framework for marine carbon removal technologies, which currently lack rigorous measurement and governance. Without such protocols, these methods cannot be included in national or international climate strategies. This research is critical for carbon markets because it addresses the verification gap that prevents ocean-based carbon credits from being traded. If successful, it could open a new pathway for carbon removal that complements land-based methods, though the scientists stress the need to avoid unforeseen ecological risks.