A model-based analysis of physical and biological controls on ice algal and pelagic primary production in Resolute Passage

• Published in: Elementa: Science of the Anthropocene
• Main Authors: Mortenson, Eric, Hayashida, Hakase, Steiner, Nadja, Monahan, Adam H., Blais, Marjolaine, Gale, Matthew A., Galindo, Virginie, Gosselin, Michel, Hu, Xianmin, Lavoie, Diane, Mundy, Christopher John
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elementa: Science of the Anthropocene 2017
• Subjects: sea ice algae; biogeochemistry model; marine Arctic; primary production; Arctic; Arctic Ocean; Canada; Canadian Arctic Archipelago; Resolute Passage; Arctic Archipelago; ArcticNet; ice algae; Phytoplankton; Sea ice
• Online Access: https://doi.org/10.1525/elementa.229; https://dspace.library.uvic.ca//handle/1828/10144

A coupled 1-D sea ice-ocean physical-biogeochemical model was developed to investigate the processes governing ice algal and phytoplankton blooms in the seasonally ice-covered Arctic Ocean. The 1-D column is representative of one grid cell in 3-D model applications and provides a tool for parameterization -development. The model was applied to Resolute Passage in the Canadian Arctic Archipelago and assessed with observations from a field campaign during spring of 2010. The factors considered to limit the growth of simulated ice algae and phytoplankton were light, nutrients, and in the case of ice algae, ice melt. In -addition to the standard simulation, several model experiments were conducted to determine the sensitivity of the simulated ice algal bloom to parameterizations of light, mortality, and pre-bloom biomass. Model results indicated that: (1) ice algae limit subsequent pelagic productivity in the upper 10 m by depleting nutrients to limiting levels; (2) light availability and pre-bloom biomass determine the onset timing of the ice algal bloom; (3) the maximum biomass is relatively insensitive to the pre-bloom biomass, but is limited by nutrient availability; (4) a combination of linear and quadratic parameterizations of mortality rate is required to adequately simulate the evolution of the ice algal bloom; and (5) a sinking rate for large detritus greater than a threshold of similar to 10 m d(-1) effectively strips the surface waters of the limiting nutrient (silicate) after the ice algal bloom, supporting the development of a deep chlorophyll maximum. EM and HH were funded via the NETCARE and ArcticNet projects. NS and DL were supported by Fisheries and Oceans Canada. VG, MG, AM, and CJM were supported by funding from Natural Sciences and Engineering Research Council of Canada (NSERC), Fonds de recherche du Quebec Nature et Technologies (FRQNT), Canada Economic Development and Polar Continental Shelf Program (PCSP) of Natural Resources Canada. Faculty Reviewed