| Description: |
does not mean to be exhaustive, but seeks to identify gaps in the observations of the Arctic sea ice coverthat, if closed, could significantly help to evaluate and improve the process- to large-scale sea ice models. Any comments or questions about this note are welcome and should be addressed directly to the authors. 2 General remarks 1. Converging to a common language: One of the main obstacles between the “observer ” and the “modeler ” communities is that they do not speakthe same “language”: the ice age viewed by asatellite (Fowleret al., 2004) is often defined differently to that of a model (Lietaer et al., 2011; Hunke and Bitz, 2009); in addition, the multiyear ice coverage can differ substantially depending on whether it is calculated as an extent (with a cutoff value for ice concentration), or as an area (Jahn et al., 2012). Even simpler, the mean ice thickness over a parcel is not a precisely defined quantity as long as the treatment of open water has not been specified explicitly. We believe that addressing this question of terminology is a prerequisite for correctly comparing observations and models, and strongly recommend that a list of “controlled vocabulary ” be set up to bridge the two communities. 2. Different users, different needs: Two subsets of modelers benefit from observations of the sea ice cover: • The small-scale (or process-scale) model developers include new parameterizationsandprocessesintheseaicemodels(e.g. theevolution of snow temperature profiles on top of sea ice (Lecomte et al., 2011)). |