Abstract
Annual sea-ice edge phytoplankton blooms occur throughout the Arctic
during the spring melt period. Our study considers how phytoplankton
spring blooms may depend on sea-ice meltwater. We extend the classic
Fisher reaction-diffusion equation to consider a time- and space-varying
death rate that represents the role of meltwater in the system. Our
results indicate that blooms peak at a characteristic distance from the
ice edge where (i) meltwater is still concentrated enough to stratify
the upper ocean such that the phytoplankton are confined near the
surface and (ii) phytoplankton have been exposed to sufficient sunlight
to allow for maximum growth. The results are qualitatively similar to
satellite data of a large bloom observed in Fram Strait in May 2019. Our
findings support the idea that sea-ice meltwater is of central
importance for Arctic phytoplankton blooms.