The spring bloom of microalgae within the bottom of sea ice provides a significant contribution to primary production in the Arctic Ocean. The aim of this research was to improve observations of the ice algae bloom using a transmitted irradiance technique to remotely estimate biomass, and to examine the influence of physical processes on biomass throughout the sea ice melt season. Results indicate that bottom ice temperature is highly influential in controlling biomass variability and bloom termination. Snow depth is also significant as it buffers ice temperature from the atmosphere and largely controls transmission of photosynthetically active radiation (PAR). The relationship between snow depth and biomass can change over the spring however, limiting biomass accumulation early on while promoting it later. Brine drainage, under-ice current velocity, and surface PAR in the absence of snow cover are also important factors. Overall this research helps to characterize the spring ice algae bloom in the Arctic by improving in situ biomass estimates and identifying primary factors controlling it.

The spring bloom of microalgae within the bottom of sea ice provides a significant contribution to primary production in the Arctic Ocean. The aim of this research was to improve observations of the ice algae bloom using a transmitted irradiance technique to remotely estimate biomass, and to examine the influence of physical processes on biomass throughout the sea ice melt season. Results indicate that bottom ice temperature is highly influential in controlling biomass variability and bloom termination. Snow depth is also significant as it buffers ice temperature from the atmosphere and largely controls transmission of photosynthetically active radiation (PAR). The relationship between snow depth and biomass can change over the spring however, limiting biomass accumulation early on while promoting it later. Brine drainage, under-ice current velocity, and surface PAR in the absence of snow cover are also important factors. Overall this research helps to characterize the spring ice algae bloom in the Arctic by improving in situ biomass estimates and identifying primary factors controlling it.