Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Large-scale vorticity generation and kinetic energy budget along the
  U.S. West Coast   We attempt to evaluate energy budget over a restricted but extremely well
studied oceanic region along the shorelines of Oregon and California. The
analysis is based on a recently updated geostrophic flow field data set
covering 22 years with daily resolution on a grid of
0.25$^\circ\times$0.25$^\circ$, and turbulent wind stress data from the
ERA-Interim reanalysis over the same geographic region with the same temporal
and spatial resolutions. Integrated 2D kinetic energy, enstrophy, wind stress
work and { kinetic energy tendency} are determined separately for the shore-
and open water regions. The empirical analysis is supported by 2D lattice
Boltzmann simulations of freely decaying vortices along a rough solid wall,
which permits to separate the pure shoreline effects and dissipation properties
of surface flow fields. Comparisons clearly demonstrate that kinetic energy and
vorticity { of the geostrophic flow field} are mostly generated along the
shorelines and advected to the open water regions, where the net wind stress
work is almost negligible. Our results support that the geostrophic flow field
is quasistationary on the timescale of a couple of days, thus total forcing is
practically equal to total dissipation. Estimates of unknown terms in the
equation of oceanic kinetic energy budget are based on other studies,
nevertheless our results suggest that { an effective} eddy kinematic viscosity
is in the order of magnitude $10^{-2}$ m$^2$/s along the shorelines, and it is
lower { by a factor of two} in the open water region.

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The categories of this paper are: math
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
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The categories of this paper are: cond-mat
32
The categories of this paper are: atom-ph