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Mixed Layer Depth

World Ocean Database 1998

The plots in this data group are of monthly mixed layer depth and mixed layer depth climatology computed from the WOD98 (World Ocean Database 1998) standard level data. Mixed layer depth is computed using two different criteria (see below) from individual WOD98 profiles, then averaged on a 1-degree latitude/longitude grid.

Temperature Criterion: Mixed layer depth is determined as the depth at which the temperature falls to 0.5 degrees C below the surface temperature.

Density Criterion: Mixed layer depth is determined as the depth at which the density difference from the sea surface is 0.125 sigma units.

For more detail see Monterey, G., and S. Levitus, 1997: Seasonal variability of mixed layer depth for the World Ocean. NOAA Atlas, NESDIS 14, 100 pp., Washington, D.C.