2006 LAYERED OCEAN MODEL WORKSHOP

Bulk mixed layer models have traditionally been used with isopycnal- coordinate ocean models. Their close adherence to energetic considerations and the fact that the ocean's planetary boundary layer is very nearly homogeneous make bulk mixed layer models appealing. While results with slowly varying forcing were quite promising, with realistically high-frequency forcing variability, bulk models have not been found to be competitive with more empirical Eulerian approaches to modeling the surface mixed layer (e.g., Halliwell, 2004). This talk will demonstrate how a refined bulk mixed layer model, when used in conjunction with 2 buffer layers is able to accurately model all of the important mixed layer processes without excessive diapycnal mixing during detrainment. This is the first bulk mixed layer model to be able to reproduce the diurnal cycle of mixing layer depth. A companion talk by Anderson et al shows how closely this approach reproduces KPP. This approach offers the potential advantage over formal hybrid approaches by allowing the model to use isopycnal coordinates as near to the surface as they are representable.