Publication Date:
2017-06-10
Description:
Large changes in the sea-ice regime of the Arctic Ocean have occurred over the last decades justifying the development of models to forecast sea-ice physics and biogeochemistry. The main goal of this study is to evaluate the performance of the Los Alamos Sea Ice Model (CICE) to simulatephysical and biogeochemical properties at time scales of a few weeks and to use the model to analyze ice algal bloom dynamics in different types of ice. Ocean and atmospheric forcing data and observations of the evolution of the sea-ice properties collected from April 18 to June 4, 2015, during the Norwegian young sea ICE expedition (N-ICE2015), were used to test the CICE model. Our results show that: (i) Model performance is reasonable for sea-ice thickness, bulk salinity, good for vertically resolved temperature, vertically averaged Chl a concentrations and standing stocks and poor for vertically resolved Chl a concentrations; (ii) Improving current knowledge about nutrient exchanges, ice algal recruitment and motion is critical to improve sea-ice biogeochemical modeling; (iii) Ice algae may bloom despite some degree of basal melting; (iv) Ice algal motility driven by gradients in limiting factors is a plausible mechanism to explain their vertical distribution; (v) Different ice algal bloom and net primary production (NPP) patterns were identified in the ice types studied suggesting that ice algal maximal growth rates will increase whilst sea-ice vertically integrated NPP and biomass will decrease, as a result of the predictable increase in the area covered by refrozen leads in the Arctic Ocean.
Print ISSN:
0148-0227
Topics:
Biology
,
Geosciences
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