Abstract.
Sea-ice
ridges
constitute
a
large
fraction
of
the
total
Arctic
sea-ice
area
(up
to
40–50
%);
nevertheless,
they
are
least
studied
part
ice
pack.
Here
we
investigate
melt
rates
using
rare
repeated
underwater
multibeam
sonar
surveys
that
cover
period
one
month
during
advanced
stage
melt.
We
show
degree
bottom
increases
with
draft
for
first-year
and
second-year
level
ice,
ridge,
an
average
0.45
m,
0.55
0.95
m
snow
in
observation
period,
respectively.
investigated
ridge
4.6
keel
draft,
42
width,
4
%
macroporosity.
While
were
times
higher
than
surface
almost
identical
responsible
40
decrease.
high
spatial
variability
cross-sectional
ranging
from
0.2
2.6
maximum
point
loss
6
m.
attribute
57
(36
%),
slope
(32
width
(27
larger
steeper
slope,
smaller
width.
The
rate
flanks
was
proportional
while
there
increased
within
10
its
corners,
comparable
Elementa Science of the Anthropocene,
Journal Year:
2023,
Volume and Issue:
11(1)
Published: Jan. 1, 2023
The
rapid
melt
of
snow
and
sea
ice
during
the
Arctic
summer
provides
a
significant
source
low-salinity
meltwater
to
surface
ocean
on
local
scale.
accumulation
this
on,
under,
around
floes
can
result
in
relatively
thin
layers
upper
ocean.
Due
small-scale
nature
these
upper-ocean
features,
typically
order
1
m
thick
or
less,
they
are
rarely
detected
by
standard
methods,
but
nevertheless
pervasive
critically
important
summer.
Observations
Multidisciplinary
drifting
Observatory
for
Study
Climate
(MOSAiC)
expedition
2020
focused
evolution
such
made
advancements
understanding
their
role
coupled
system.
Here
we
provide
review
Arctic,
with
emphasis
new
findings
from
MOSAiC.
Both
prior
recent
observational
datasets
indicate
an
intermittent
yet
long-lasting
(weeks
months)
layer
0.1
1.0
thickness,
large
spatial
range.
presence
impacts
physical
system
reducing
bottom
allowing
formation
via
false
growth.
Collectively,
bottoms
reduce
atmosphere-ocean
exchanges
momentum,
energy,
material.
far-reaching,
including
acting
as
barrier
nutrient
gas
exchange
impacting
ecosystem
diversity
productivity.
Elementa Science of the Anthropocene,
Journal Year:
2023,
Volume and Issue:
11(1)
Published: Jan. 1, 2023
Sea-ice
ridges
constitute
a
large
fraction
of
the
ice
volume
in
Arctic
Ocean,
yet
we
know
little
about
evolution
these
masses.
Here
examine
thermal
and
morphological
an
first-year
sea-ice
ridge,
from
its
formation
to
advanced
melt.
Initially
mean
keel
depth
was
5.6
m
sail
height
0.7
m.
The
initial
rubble
macroporosity
(fraction
seawater
filled
voids)
estimated
at
29%
drilling
43%–46%
buoy
temperature.
From
January
until
mid-April,
ridge
consolidated
slowly
by
heat
loss
atmosphere
total
layer
growth
during
this
phase
mid-April
mid-June,
there
sudden
increase
consolidation
rate
despite
no
conductive
flux.
We
surmise
change
related
decreased
due
transport
snow-slush
via
adjacent
open
leads.
In
period,
thickness
increased
2.1
At
peak
melt
June–July
suggest
that
refreezing
surface
snow
meltwater
(the
latter
only
15%
consolidation).
used
morphology
parameters
calculate
hydrostatic
equilibrium
obtained
more
accurate
estimate
actual
keel,
correcting
2.2
2.8
for
average
consolidation.
This
approach
also
allowed
us
0.3
m,
June–July,
accompanied
decrease
draft
0.9
An
mass
balance
indicated
which
rapid
mode
April
June.
By
resulted
drastic
interior
while
flanks
had
or
macroporosity.
These
results
are
important
understanding
role
keels
as
sources
sinks
sanctuary
ice-associated
organisms
pack
ice.
The cryosphere,
Journal Year:
2023,
Volume and Issue:
17(11), P. 4873 - 4887
Published: Nov. 20, 2023
Abstract.
Sea-ice
ridges
constitute
a
large
fraction
of
the
total
Arctic
sea-ice
area
(up
to
40
%–50
%);
nevertheless,
they
are
least
studied
part
ice
pack.
Here
we
investigate
melt
rates
using
rare,
repeated
underwater
multibeam
sonar
surveys
that
cover
period
1
month
during
advanced
stage
melt.
Bottom
increases
with
draft
for
first-
and
second-year
level
first-year
ridge,
an
average
0.46,
0.55,
0.95
m
snow
in
observation
period,
respectively.
On
average,
ridge
had
4.6
keel
bottom
draft,
was
42
wide,
4
%
macroporosity.
While
were
3.8
times
higher
than
ice,
surface
almost
identical
but
responsible
decrease.
Average
cross-sectional
ranged
from
0.2
2.6
m,
maximum
point
loss
6
showcasing
its
spatial
variability.
We
attribute
57
(surface
bottom)
variability
(36
%),
slope
(32
width
(27
larger
steeper
slope,
smaller
width.
The
rate
flanks
proportional
increased
within
10
corners
between
these
comparable
ice.
Elementa Science of the Anthropocene,
Journal Year:
2025,
Volume and Issue:
13(1)
Published: Jan. 1, 2025
Melt
ponds
are
a
common
feature
of
the
Arctic
sea-ice
environment
during
summer,
and
they
play
an
important
role
in
exchange
heat
water
vapor
between
ocean
atmosphere.
We
report
results
time-series
study
CO2
dynamics
within
melt
(and
nearby
lead)
related
fluxes
with
atmosphere
summer-to-autumn
transition
central
Ocean
Multidisciplinary
drifting
Observatory
for
Study
Climate
(MOSAiC)
expedition.
In
late
summer
2020,
low-salinity
meltwater
was
distributed
throughout
ponds,
undersaturation
pCO2
drove
net
influx
from
The
layer
subsequently
thinned
due
to
seawater
influx,
strong
gradient
salinity
low-pCO2
observed
at
interface
beginning
September.
Mixing
underlying
drives
significant
drawdown
as
result
non-linearities
carbonate
chemistry.
By
middle
September,
stratification
had
dissipated.
Subsequent
freezing
then
began,
cooling
wind-induced
ice
floes
caused
mixing
through
bottom
pond.
pond
reached
300
µatm
exchanging
seawater.
However,
gas
impeded
by
formation
impermeable
freshwater
on
surface
pond,
flux
nearly
zero
into
which
no
longer
sink
atmospheric
CO2.
Overall,
this
area
(both
lead
water)
act
moderate
sinks
EarthArXiv (California Digital Library),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Dec. 8, 2023
An
international
and
interdisciplinary
sea
ice
drift
expedition,
the
‘The
Multidisciplinary
drifting
Observatory
for
Study
of
Arctic
Climate‘
(MOSAiC),
was
conducted
from
October
2019
to
September
2020.
The
aim
MOSAiC
study
interconnected
physical,
chemical
biological
characteristics
processes
atmosphere
deep
central
system.
ecosystem
team
addressed
current
knowledge
gaps
explored
unknown
properties
over
a
complete
seasonal
cycle
focusing
on
three
major
research
areas:
biodiversity,
biogeochemical
cycles
linkages
environment.
In
addition
coverage
core
along
cycle,
dedicated
projects
covered
specific
habitats,
or
organisms
higher
taxonomic
temporal
resolution.
A
wide
range
sampling
approaches
sampling,
coring,
lead
CTD
rosette-based
water
plankton
nets,
ROVs
acoustic
buoys
applied
address
science
objectives.
Further,
process-related
measurements
e.g.
productivity
patterns,
migrations
diversity
shifts
were
both
in
situ
onboard
RV
Polarstern.
This
paper
provides
detailed
overview
used
main
It
highlights
program
examples
two
habitat-
process-specific
projects.
First
results
presented
include
high
activities
winter
time
discovery
hotspots
underexplored
habitats.
unique
interconnectivity
coordinated
efforts
also
revealed
insights
into
cross-disciplinary
interactions
like
impact
biota
cloud
formation.
further
presents
lessons
learned
conducting
such
demanding
field
campaign
an
outlook
spin-off
be
next
years.
Abstract.
Sea-ice
ridges
constitute
a
large
fraction
of
the
total
Arctic
sea-ice
area
(up
to
40–50
%);
nevertheless,
they
are
least
studied
part
ice
pack.
Here
we
investigate
melt
rates
using
rare
repeated
underwater
multibeam
sonar
surveys
that
cover
period
one
month
during
advanced
stage
melt.
We
show
degree
bottom
increases
with
draft
for
first-year
and
second-year
level
ice,
ridge,
an
average
0.45
m,
0.55
0.95
m
snow
in
observation
period,
respectively.
investigated
ridge
4.6
keel
draft,
42
width,
4
%
macroporosity.
While
were
times
higher
than
surface
almost
identical
responsible
40
decrease.
high
spatial
variability
cross-sectional
ranging
from
0.2
2.6
maximum
point
loss
6
m.
attribute
57
(36
%),
slope
(32
width
(27
larger
steeper
slope,
smaller
width.
The
rate
flanks
was
proportional
while
there
increased
within
10
its
corners,
comparable
Abstract.
Sea-ice
ridges
constitute
a
large
fraction
of
the
total
Arctic
sea-ice
area
(up
to
40–50
%);
nevertheless,
they
are
least
studied
part
ice
pack.
Here
we
investigate
melt
rates
using
rare
repeated
underwater
multibeam
sonar
surveys
that
cover
period
one
month
during
advanced
stage
melt.
We
show
degree
bottom
increases
with
draft
for
first-year
and
second-year
level
ice,
ridge,
an
average
0.45
m,
0.55
0.95
m
snow
in
observation
period,
respectively.
investigated
ridge
4.6
keel
draft,
42
width,
4
%
macroporosity.
While
were
times
higher
than
surface
almost
identical
responsible
40
decrease.
high
spatial
variability
cross-sectional
ranging
from
0.2
2.6
maximum
point
loss
6
m.
attribute
57
(36
%),
slope
(32
width
(27
larger
steeper
slope,
smaller
width.
The
rate
flanks
was
proportional
while
there
increased
within
10
its
corners,
comparable
Abstract.
Sea-ice
ridges
constitute
a
large
fraction
of
the
total
Arctic
sea-ice
area
(up
to
40–50
%);
nevertheless,
they
are
least
studied
part
ice
pack.
Here
we
investigate
melt
rates
using
rare
repeated
underwater
multibeam
sonar
surveys
that
cover
period
one
month
during
advanced
stage
melt.
We
show
degree
bottom
increases
with
draft
for
first-year
and
second-year
level
ice,
ridge,
an
average
0.45
m,
0.55
0.95
m
snow
in
observation
period,
respectively.
investigated
ridge
4.6
keel
draft,
42
width,
4
%
macroporosity.
While
were
times
higher
than
surface
almost
identical
responsible
40
decrease.
high
spatial
variability
cross-sectional
ranging
from
0.2
2.6
maximum
point
loss
6
m.
attribute
57
(36
%),
slope
(32
width
(27
larger
steeper
slope,
smaller
width.
The
rate
flanks
was
proportional
while
there
increased
within
10
its
corners,
comparable
