How does rising atmospheric CO2 affect marine organisms?

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Fine and Not-So-Fine Sea Ice Models
Reference
Holland, D.M.  2001.  An impact of subgrid-scale ice-ocean dynamics on sea-ice cover.  Journal of Climate 14: 1585-1601.

What was done
According to the author, "the present situation with respect to the state-of-the-art global climate models is that some physical processes are absent from the models and, with the rather coarse-resolution grids used, some physical processes are ill resolved ... and therefore in practical terms missing from the simulations," which facts lead the author to "question whether the simulations obtained from such models are in fact physically meaningful."  Thus, the author conducted an analysis to determine the difference in model evolution of sea ice cover using a relatively coarse-resolution grid verses a fine-resolution grid, with specific emphasis on the presence and treatment of a mesoscale ocean eddy and its influence on sea ice cover.

What was learned
Resolving the ocean eddy field using the fine-resolution model was found to have a measurable impact on sea ice concentration, implying that a "fine-resolution grid may have a more efficient atmosphere-sea ice-ocean thermodynamic exchange than a coarse one."

What it means
In the author's own words, the results of this study demonstrate "yet again that coarse-resolution coupled climate models are not reaching fine enough resolution in the polar regions of the world ocean to claim that their numerical solutions have reached convergence."  Clearly, the models still have a long way to go before their resolution becomes fine enough to include (or adequately parameterize) all the important physical processes related to sea ice cover, and possibly those of many other climate phenomena as well.