Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A new Lagrangian drift mechanism due to current-bathymetry interactions:
  applications in coastal cross-shelf transport   We show that in free surface flows, a uniform, streamwise current over
small-amplitude rippled bottom topography generates cross-stream drift
velocity. This Lagrangian drift, referred to as the current-bathymetry
interaction induced drift (CBIID), is specifically understood in the context of
a simplified nearshore environment, consisting of uniform alongshore current,
onshore propagating surface waves, and monochromatic rippled bathymetry making
an oblique angle with the shoreline. CBIID is found to originate from the
steady, non-homogeneous solution of the governing system of equations. Similar
to Stokes drift induced by surface waves, CBIID can also have important
implications in cross-shelf tracer transport. CBIID increases with particle's
depth, bottom ripple's wavelength and amplitude, and the magnitude of the
alongshore current. Moreover, maximum cross-shelf transport by CBIID is
obtained when the bottom ripple wave-vector approximately makes $\pi/4$ angle
with the shoreline. Depending on the angle between the alongshore current and
the bottom ripple wave-vector, CBIID can lead to onshoreward or offshoreward
tracer transport. Unlike Stokes drift, particle excursions due to
current-bathymetry interactions might not be small, hence analytical
expressions based on small-excursion approximation could be inaccurate. We
provide an alternative $z$-bounded approximation, which provides highly
accurate expressions of drift velocity and time period for particles near the
free surface. Realistic parametric analysis reveals that in situations where
the Stokes drift and CBIID velocities have comparable magnitudes, they are
order separated both in length and time scales. We infer that high-resolution
coastal bathymetry maps are crucial for accurate predictions of tracer
transport pathways in the nearshore environment.

7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
11
The categories of this paper are: hep-lat
6
The categories of this paper are: astro-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
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The categories of this paper are: q-fin
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The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
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The categories of this paper are: eess
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The categories of this paper are: math-ph
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The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
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The categories of this paper are: supr-con