Open AccessObserving global ocean topostrophy
Author(s) -
Holloway Greg
Publication year - 2008
Publication title -
journal of geophysical research: oceans
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2007jc004635
Subject(s) - ocean current , climatology , latitude , grid , the arctic , general circulation model , geology , current meter , current (fluid) , arctic , meteorology , environmental science , atmospheric sciences , geodesy , physics , oceanography , climate change
Recent publications have evaluated topostrophy, τ ≡ f × V · ∇ D where is f Coriolis, V is velocity, and ∇ D is gradient of total depth, as a means of comparing models' circulations. Some results are striking. Comparing four global models, two with modest grid size and two with fine grids, Merryfield and Scott (2007) show that finer grid models are characterized by more positive τ , especially at greater depths and higher latitudes. Among nine Arctic Ocean models, Holloway et al. (2007) find τ in three of the models quite distinct from the other six, a result shown to depend upon subgrid eddy parameterization. From different choices of numerical method within the same model, Penduff et al. (2007) show that improved numerical representations support more positive τ . Can these model results be compared with observations? A global compilation has been prepared from 17120 current meter records, spanning 83087 current meter‐months. The compilation tends to confirm modeling progress achieved by finer resolution, improved parameterizations and better representations. A new characterization of global ocean circulation emerges, with suggestive dynamical insights.