Focus 1: How does loss of land ice affect coastal runoff and biogeochemical cycling in Arctic coastal areas?
Focus 1 will quantify current temporal and spatial variability in catchment and glacial runoff to coastal areas, and the biogeochemical cycling rates in the coastal runoff plume.
Theme 1.1 - Quantify runoff patterns across catchment characteristics and consequences for bio-geochemical pools and cycling in coastal areas.
Freshwater runoff from land affects coastal water quality and functioning, particularly in plumes near river outlets. Despite some scattered studies, a standardised comparison of runoff patterns along Greenland’s east coast is absent, limiting our understanding of how catchment characteristics (i.e., ice, vegetation, and snow cover) drive runoff patterns of water, carbon and nutrients from land to coast across a globally important climate gradient. We will leverage existing GIOS data supplemented with new data as necessary using sites along the north-south gradient. As the river freshwater mixes with saline marine water in run-off plumes, physical and biological transformations occur, including flocculation of organic material and desorption of inorganic and organic nutrients from particles. Little is understood about dynamics in run-off plumes and their impact on nutrient and carbon availability. By linking measurements across the gradient from river to coastal plume ecosystems, we provide a new and novel quantification of transport and biogeochemical transformation rates of carbon and nutrients from land to sea across the Arctic climate gradient.
Theme 1.2 - Quantification and upscaling of freshwater release from land and marine terminating glaciers.
The interaction between glacier fronts and coastal waters is critical for predicting future ice loss and coastal productivity. Sparse direct observations indicate that freshwater fluxes from glaciers significantly influence fjord circulation, ice frontal melt, and ecosystem habitability. In West Greenland, marine-terminating glaciers release meltwater, causing a mixing with warm Atlantic Water and upwelling of deep fjord waters, supporting high primary productivity. In Northeast Greenland, however, glacier termini interact with a thicker colder and fresher Polar Water layer. In CIFAR we will investigate the seasonal signature of this discharge and determine whether it is a general pattern for glaciers in contact with Polar Water. If so, there may be a strong link between the stability of glaciers in East Greenland and the sea ice formation along the Russian Arctic shelf where this cold water is formed. To upscale dynamics of glacial plumes, surface temperatures and calving events, we will combine ground truth observations with remote sensing products. A new earth observing CubeSat mission, DISCO2 (lead by a PhD student of SR), is set for launch in 2025. It will be deployed into a sun-synchronous polar orbit and will pass close to the Earth poles 15 times a day and is designed for the CIFAR study area. The satellite payload consists of two optical cameras and a thermal camera and a unique capability for in-orbit data analysis applying machine learning algorithms. The combination of cameras will provide an exceptional opportunity for the study of glaciers and surface temperature dynamics and for upscaling beyond our study region.
