Collaborative Research: Warming and irradiance measurements in the Arctic: Determining the link betweensolar energy absorbtion and surface warming through long term observations

The objectives of this research are to quantify the connection between seasonal warming of arctic surface waters and the absorption of solar energy, and additionally to identify the presence and seasonal cycling of materials responsible for this absorption. Seasonal changes in the attenuation of solar radiation within the sea ice and upper 30m of the water column will be measured at high temporal resolution (hourly) by a new proof of concept buoy system. Temperature and PAR (photosynthetically active radiation) irradiance measurements will be made using optical sensors paired with thermisters within the water column and sea ice. A fluorometer will be used to quantify chlorophyll, colored dissolved organic material (CDOM) and light backscattering within surface waters. These sensors will be used to calculate diffuse attenuation coefficients (Kd) within the ice and water column, and to determine the seasonal cycling of phytoplankton and CDOM under the ice. The relationship between these optical and temperature observations will enable one to constrain the daily water column absorption component of the Arctic heating budget. The ultimate goal of this concept would see a network of these buoys throughout the Arctic, in both ice-covered and open waters. The work plan includes several deployments in multiyear ice, including the Beaufort gyre and the Geomission ice base in early spring. Data at this site will be augmented by additional measurements made whilst at the camp, along with complementary studies by other Geomission projects. Results will be disseminated through collaboration with Science Alliance Live, at Polar Science Weekend, and in curricula at the University of Washington. Buoy data will also be visualized in near real time on the project website. All data will be submitted within 1 year to CADIS.