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Ocean mixed layer depth: A subsurface proxy of ocean-atmosphere | 
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variability | 
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 | 
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K. Lorbacher, D. Dommenget, P.P. Niiler and R.E. Davis, SIO | 
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 | 
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The spatial and temporal variability of dominant atmospheric forcing | 
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mechanisms setting up the structure of the ocean turbulent surface layer | 
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are well documented. To quantify, understand and ultimately predict | 
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ocean-atmosphere interactions on climate relevant time scales | 
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identifying the depth of this layer, in addition to the SST, is cruical. | 
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However, | 
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observed ocean mixed layer depths (MLDs) -- in the quality of SST | 
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observations -- | 
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do not exist yet. | 
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 | 
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We investigate hydrographic data with high and low vertical resolution | 
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obtained during the WOCE period to determine the quality of the observed | 
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ocean MLD applying two criteria for this depth provided by the recent | 
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literature. Considerable discrepancies in the results motivates us to | 
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optimize a criterion estimating ocean MLDs. We include a solution of the | 
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global ECCO state estimation in our analysis to test the sensitivity of | 
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both observed and diagnosed MLDs and their climate variability to | 
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different criteria. |