Pathways and Impact of Greenland’s Glacial Meltwater on Regional Ocean Chemistry and Biology
2015 OCCI Funded Project
Warming of both the atmosphere and ocean in the high latitude North Atlantic has led to the retreat of glaciers in southern Greenland, resulting in an unprecedented ice loss from the Greenland Ice Sheet. One well-known consequence of these changes is a rise in sea level. Another important, but largely neglected consequence is the impact of the increased meltwater discharge on the downstream marine ecosystems. By affecting stratification and the chemical properties of surface waters (including nutrient concentrations), increased meltwater is expected to have repercussions on the timing, magnitude, and community composition of phytoplankton blooms and, therefore, on the rest of the food chain. Indeed, recent studies have hypothesized that increased glacial meltwater input may impact biochemical cycles not only locally, in the fjords where the glaciers terminate, but also regionally over the subpolar North Atlantic. Notwithstanding the potential far-reaching impacts, the role of glacial meltwater as a control over phytoplankton blooms remains anecdotal due to a lack of observations.
Through a unique interdisciplinary collaboration between WHOI scientists, including a postdoctoral scholar and a student enrolled in WHOI’s new undergraduate program, we propose to map the distribution of glacial meltwater and its impact on nutrient chemistry and phytoplankton communities downstream of one of Greenland’s largest glaciers. The proposed work leverages a funded cruise to SE Greenland and builds on the ongoing extensive physical sampling of the region (Straneo), and chemical sampling of similar systems in West Greenland (Charette), thereby linking several major Arctic research themes at the institution. The proposed measurements will be the first integrated biological (Cape and Sosik), physical (Straneo), and chemical measurements (Charette) from this kind of environment. Funds are requested to purchase and ship instrumentation and supplies for the collection of water samples and cover their analysis. The goal of these measurements is to link processes across the ice–ocean– ecosystem continuum, thereby contributing significantly to our understanding of the consequences of Greenland ice loss on the ocean and addressing one of the Ocean Climate Change Institute’s themes. We anticipate that this study will lay the foundation for future interdisciplinary collaborations among WHOI scientists in an expanding area of research.