Near-slope turbulence in a Rockall canyon
Deep Sea Research Part I Oceanographic Research Papers,
Journal Year:
2024,
Volume and Issue:
206, P. 104277 - 104277
Published: Feb. 29, 2024
The
acknowledgement
of
the
importance
small-scale
turbulent
mixing
for
redistribution
heat,
nutrients
and
suspended
matter
in
ocean
has
led
to
renewed
interest
breaking
internal
waves
at
underwater
topography.
This
follows
from
observations
that
turbulence
intensity
increases
interior
seafloor.
As
two-dimensional
models
require
reduction
buoyancy
flux
vicinity
seafloor
allow
up-welling
flows,
question
is
how
thin
such
a
layer
reduced
above
can
be.
From
an
observational
study
this
subject,
we
present
400-day
moored
high-resolution
temperature
measurements
Rockall
canyon
between
0.9
<
h
152
m
steeply
sloping
thalweg-seafloor.
In
area,
Thorpe-scale
calculated
dissipation
rate
predominantly
governed
by
semidiurnal
tides.
Tidal-mean
profiles
increase
with
depth,
together
inertial-subrange
temperature-variance.
A
distinct
further
found
lower
4
across
which
variance
decreased.
was
observed
during
most
tidal
phase,
except
warming
when
decrease
few
meters.
showed
change
distribution
stratification
transition
little
=
m,
via
dominant
convection-turbulence
5
shear-turbulence
>
30
as
established
spectral
information.
lack
mean
near-seafloor
buoyancy-flux
hypothesized
be
compensated
3D-effects,
temporary
effects,
less
steep
slope
or
none
all.
Language: Английский
Breaking internal waves on sloping topography: connecting parcel displacements to overturn size, interior-boundary exchanges, and mixing
EarthArXiv (California Digital Library),
Journal Year:
2024,
Volume and Issue:
unknown
Published: April 5, 2024
Internal
waves
impinging
on
sloping
topography
can
generate
mixing
through
the
formation
of
near-bottom
bores
and
overturns
in
what
has
been
called
`internal
swash'
zone.
Here
we
investigate
generated
during
these
breaking
events,
subsequent
ventilation
bottom
boundary
layer,
across
a
realistic
non-dimensional
parameter
space
for
ocean
using
three-dimensional
large
eddy
simulations.
Waves
overturn
break
at
two
points
wave
period:
when
downslope
velocity
is
strongest
rapid
onset
dense,
upslope
bore.
From
first
overturning
bore
to
expulsion
fluid
into
interior,
there
strong
dependence
length
scale
defined
by
ratio
over
background
buoyancy
frequency,
an
upper
bound
vertical
parcel
displacement
internal
cause.
While
this
energetically-motivated
often
seen
context
lee
generation
topography,
results
discussed
here
suggest
same
be
used
determine
size
near-boundary
overturns,
strength
ensuing
turbulent
mixing,
along-isopycnal
intrusions
ejected
from
layer.
Consideration
volume
budget
region
highlights
spatial
temporal
variability
that
must
taken
account
determining
water-mass
transformation
process.
Language: Английский
Deep inflow transport and dispersion in the Gulf of St. Lawrence revealed by a tracer release experiment
Communications Earth & Environment,
Journal Year:
2024,
Volume and Issue:
5(1)
Published: June 20, 2024
Abstract
The
Gulf
of
St.
Lawrence
is
increasingly
affected
by
bottom
water
hypoxia;
however,
the
timescales
and
pathways
deep
transport
remain
unclear.
Here,
we
present
results
from
Deep
Tracer
Release
eXperiment
(TReX
Deep),
during
which
an
inert
SF
5
CF
3
tracer
was
released
inshore
Cabot
Strait
at
279
m
depth
to
investigate
inflow
mixing
rates.
Dispersion
also
assessed
via
neutrally-buoyant
Swish
floats.
Our
findings
indicate
that
moves
inland
0.5
cm
s
−1
,
with
effective
lateral
diffusivity
2
×
10
over
1
year.
Simplified
1D
simulations
suggest
should
reach
estuary
head
in
1.7
years,
bulk
arriving
after
4.7
years.
Basin-wide
vertical
around
−5
year;
increases
near
basin
slopes,
suggesting
turbulent
boundary
processes
influence
mixing.
These
are
compared
Lagrangian
a
regional
3D
model
evaluate
capacity
dispersion
Gulf.
Language: Английский
Power That Drives Circulation of the Atmosphere and Oceans
SpringerBriefs in earth system sciences,
Journal Year:
2024,
Volume and Issue:
unknown, P. 111 - 130
Published: Jan. 1, 2024
Language: Английский
Reply on CC1
Published: Nov. 18, 2024
The
extent
of
anthropogenic
influence
on
the
Earth’s
climate
warrants
studies
ocean
as
a
major
player.
circulation
is
important
for
transporting
properties
like
heat,
carbon
and
nutrients.
A
supposed
conduit
Atlantic
Meridional
Overturning
Circulation
(AMOC).
As
AMOC
complex
nonlinear
dynamical
system,
it
challenging
to
predict
its
potential
collapse
and/or
reversal
direction
from
statistical
viewpoint
using
single
parameter
sea-surface
temperature
or
freshwater
influx
in
numerical
models.
However,
argued
this
note
supported
by
spectra
observations,
physical
processes
such
transport
sub-mesoscale
eddies
turbulence-generating
breaking
internal
waves
that
are
not
incorporated
these
models
will
alter
parameters,
thereby
analyses.
This
may
lead
feed-back
mechanisms
property
gradients
density
stratification
so
collapse.
Language: Английский
Reply on RC3
Published: Nov. 18, 2024
The
extent
of
anthropogenic
influence
on
the
Earth’s
climate
warrants
studies
ocean
as
a
major
player.
circulation
is
important
for
transporting
properties
like
heat,
carbon
and
nutrients.
A
supposed
conduit
Atlantic
Meridional
Overturning
Circulation
(AMOC).
As
AMOC
complex
nonlinear
dynamical
system,
it
challenging
to
predict
its
potential
collapse
and/or
reversal
direction
from
statistical
viewpoint
using
single
parameter
sea-surface
temperature
or
freshwater
influx
in
numerical
models.
However,
argued
this
note
supported
by
spectra
observations,
physical
processes
such
transport
sub-mesoscale
eddies
turbulence-generating
breaking
internal
waves
that
are
not
incorporated
these
models
will
alter
parameters,
thereby
analyses.
This
may
lead
feed-back
mechanisms
property
gradients
density
stratification
so
collapse.
Language: Английский