Modelling primary production dynamics in the Arctic under changing sea ice conditions

Abstract

A dramatic decline in sea ice is underway in the Arctic and we have reason to anticipate complete summer melting within this half of the century. With our current understanding of the ecological effects of this change limited, and Earth system models not yet accounting for sympagic (sea ice ecosystem) primary production, this study has been motivated to contribute towards efforts to effectively model this system. With the aim of investigating the role of sea ice in the primary production dynamics in the Arctic, an existing nutrient-phytoplankton-zooplankton-detritus (NPZD) biogeochemical model has been extended to include a parameterised ice module and sympagic primary production via an ice algae variable. This model revealed a picture of how the modelled ice algae, phytoplankton and zooplankton entities fared under varying levels of ice cover, providing a potential progression of the basic bloom dynamics in pelagic-sympagic ecosystems in which total productivity increases with reduced ice cover. Sensitivity analysis has been conducted, with considerations offered for further tests, means of model refinements and potential future developments.