Seasonal decay and break-up of sea ice in the Arctic coastal domain

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The decline of Arctic sea ice is one of the most prominent signals of climate change on Earth. Particularly the thick, multiyear ice is in rapid decline, indicating that the state of the Arctic Ocean is undergoing a shift towards a seasonal sea ice regime with new emerging open water areas. The landfast ice fringing the shores freezes up later, breaks up earlier, and is generally becoming less safe. Coastal communities around the Arctic have raised concern as they depend on the stability of the landfast ice for their subsistence hunting and travel. Less sea ice and more open water allows sunlight to heat the ocean and melt ice more rapidly, resulting in more open water - this is the well-known ice-albedo feedback loop. The Arctic Ocean is also receiving more freshwater from river runoff, glacier meltwater and precipitation. Thus, the Arctic marine environment is becoming both warmer and fresher, and the reduction in sea ice is linked to increased storminess, coastal erosion and permafrost melt. My research involves fieldwork in Arctic coastal communities, in ice camps, or onboard ships to observe and better understand the processes and climate feedbacks that control the seasonal and interannual change of Arctic sea ice. The focus of this research program is on the seasonally sea ice covered coastal and nearshore environment, or the so-called costal domain. The research objectives are to investigate: 1) the interplay between the components of the surface energy balance and the melt progression of the sea ice; 2) how ice melting affects the propagation of sunlight through the sea ice into the water column; and 3) how the seasonal decay and breakup of sea ice in the coastal and nearshore zone has changed over the last decades as a function of thermal decay (i.e., objectives 1 and 2) and external influences from the adjacent terrestrial (warm air advection, impurities, freshwater runoff) and marine domains (oceanic heat, waves, tides, storm surges). With these objectives, I will tackle phenomena that are at the heart of understanding the changing Arctic coastal sea ice environment, which is of particular concern to local residents and land users. Our ability to predict how the marine- and climate system in the Arctic will change, and how ecosystems will respond, rests on understanding the interactions between the sea ice, the ocean and the surrounding terrestrial system. The three objectives of this research program are interrelated, and as such designed as collaborative yet distinct individual projects for 6 PhD, 4 MSc and 5 BSc students. The outcome of this research will advance our knowledge of sea ice processes and climate feedbacks in the new emerging state of the Arctic Ocean, train students in Arctic marine research, involve northern residents in the research, and ultimately, benefit Northerners by improving climate predictions and process understanding that will help communities and various levels of government adapt to climate change.