This project aims to study the carbon dynamics in the Godthåbsfjord during a full annual cycle. With the projected changes like increased oceanic CO₂ uptake, strong changes in the carbon dynamics and marine chemistry are expected. This is likely to have a fundamental impact on many ecosystem processes as well. Recent studies indicate that Arctic fjord systems are a strong sink for CO₂ but the driving factors for this uptake and implication on water chemistry (e.g. pH) are still unknown. This project aims to understand the role of different processes in carbon dynamics in a subarctic fjordsystems affected by glacial input. By studying the spatial and temporal variation in chemical variables in combination with primary production (primary production group) and grazing (zooplankton group) data, the role of the different drivers can be quantified. During the campaigns, water chemistry will be studied from glacier to open ocean. From the collected water, DIC, pH, alkalinity and pCO₂ are quantified to study the inorganic carbon dynamics. Nutrients (NH₄, NO_x, PO₄, DSi, biogenic Si), chlorophyll, oxygen, suspended matter, particulate and dissolved organic carbon and the oxygen isotope ratio (indication on fraction glacial melt) will be determined.

Site: Sanna cruise, Godthåbsfjorden, Nuuk, Greenland

PI: Lorenz Meire