G Holloway, F Dupont, E Golubeva, S Haekkinen, E Hunke, M Jin, M Karcher, F Kauker, M Maltrud, M AMorales Maqueda, W Maslowski, G Platov, D Stark, M Steele, T Suzuki, J Wang, and J Zhang (2007)
Water properties and circulation in Arctic Ocean models
Journal of Geophysical Research-Oceans 112(C4).
As a part of the Arctic Ocean Model Intercomparison Project, results
from 10 Arctic ocean/ice models are intercompared over the period
1970 through 1999. Models' monthly mean outputs are laterally integrated
over two subdomains (Amerasian and Eurasian basins), then examined
as functions of depth and time. Differences in such fields as averaged
temperature and salinity arise from models' differences in parameterizations
and numerical methods and from different domain sizes, with anomalies
that develop at lower latitudes carried into the Arctic. A systematic
deficiency is seen as AOMIP models tend to produce thermally stratified
upper layers rather than the ``cold halocline'', suggesting missing
physics perhaps related to vertical mixing or to shelf-basin exchanges.
Flow fields pose a challenge for intercomparison. We introduce topostrophy,
the vertical component of V x del D where V is monthly mean velocity
and del D is the gradient of total depth, characterizing the tendency
to follow topographic slopes. Positive topostrophy expresses a tendency
for cyclonic ``rim currents''. Systematic differences of models'
circulations are found to depend strongly upon assumed roles of unresolved
eddies.