Life Cycle Assessment of Arctic Kelp Production in Greenland: From Offshore Cultivation to Food Preparation

Can kelp farming provide a low-impact food source within Arctic marine food systems? This study presents the first life cycle assessment of kelp production in Greenland, assessing environmental impacts from offshore cultivation and on-site freezing through export to Denmark for downstream processing into ready-to-eat fermented kelp-based food products, using empirically grounded operational data. Particular attention is given to discrepancies between expected and realised biomass yields. Results show that life cycle impacts per kilogram of wet harvested kelp are highly sensitive to realised yields, with climate change impacts increasing from 1.00 to 3.83 kg CO2-eq kg−1 under observed yield conditions. Offshore cultivation infrastructure and interregional transport dominate environmental burdens, while downstream processing contributes less. At the food-product level, four fermented kelp-based products are evaluated and compared with cabbage-based analogues. Kelp-based products exhibit lower land-use impacts but higher climate change and freshwater eutrophication impacts across multiple functional units. Additionally, kelp harvesting results in quantified removal of nitrogen and phosphorus from the marine environment. Overall, the findings indicate that kelp farming can represent an environmentally viable component of Arctic food systems, with yield stability and logistics identified as key determinants of sustainability.