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Mixed Layer Depth Comparisons

The carbon model requires mixed layer depth (MLD) as an input variable. It is essential that the best estimation of MLD be used as input. These pages describe the rationale for selection of a final input set for processing.

NCODA MLD Values and Comparison with NCODA/TOPS ILD Values

NCODA replaced OTIS in October of 2004. The temperature model was improved, as was the haline circulation model. However, while the salinity model improved, the new model rendered the mixed layer depths relatively useless (variations in density-space increased, resulting in very shallow MLD values). Given the quality of NCODA/TOPS ild values, it is clear that the temperature fields are fine, and that the trouble with the density values is coming from the salinity.

However, while the mld values are off, there is also a change in the ild fields: they are now closer in character to the OTIS mld values than the previous OTIS/TOPS ild values were. We shall see just how close on the next page.