<s>
CICE	B-Application
(	O
)	O
is	O
a	O
computer	B-Application
model	I-Application
that	O
simulates	O
the	O
growth	O
,	O
melt	O
and	O
movement	O
of	O
sea	O
ice	O
.	O
</s>
<s>
It	O
has	O
been	O
integrated	O
into	O
many	O
coupled	O
climate	B-Application
system	I-Application
models	I-Application
as	O
well	O
as	O
global	O
ocean	B-Application
and	O
weather	B-Application
forecasting	I-Application
models	I-Application
and	O
is	O
often	O
used	O
as	O
a	O
tool	O
in	O
Arctic	O
and	O
Southern	O
Ocean	B-Application
research	O
.	O
</s>
<s>
CICE	B-Application
development	O
began	O
in	O
the	O
mid-1990s	O
by	O
the	O
United	O
States	O
Department	O
of	O
Energy	O
(	O
DOE	O
)	O
,	O
and	O
it	O
is	O
currently	O
maintained	O
and	O
developed	O
by	O
a	O
group	O
of	O
institutions	O
in	O
North	O
America	O
and	O
Europe	O
known	O
as	O
the	O
CICE	B-Application
Consortium	O
.	O
</s>
<s>
Its	O
widespread	O
use	O
in	O
earth	O
system	O
science	O
in	O
part	O
owes	O
to	O
the	O
importance	O
of	O
sea	O
ice	O
in	O
determining	O
Earth	O
's	O
planetary	O
albedo	O
,	O
the	O
strength	O
of	O
the	O
global	O
thermohaline	O
circulation	O
in	O
the	O
world	O
's	O
oceans	O
,	O
and	O
in	O
providing	O
surface	O
boundary	O
conditions	O
for	O
atmospheric	B-Application
circulation	O
models	O
,	O
since	O
sea	O
ice	O
occupies	O
a	O
significant	O
proportion	O
(	O
4-6	O
%	O
)	O
of	O
earth	O
's	O
surface	O
.	O
</s>
<s>
CICE	B-Application
is	O
a	O
type	O
of	O
cryospheric	O
model	O
.	O
</s>
<s>
Development	O
of	O
CICE	B-Application
began	O
in	O
1994	O
by	O
Elizabeth	O
Hunke	O
at	O
Los	O
Alamos	O
National	O
Laboratory	O
(	O
LANL	O
)	O
.	O
</s>
<s>
The	O
National	O
Center	O
for	O
Atmospheric	B-Application
Research	O
(	O
NCAR	O
)	O
was	O
the	O
first	O
to	O
incorporate	O
CICE	B-Application
into	O
a	O
global	B-Application
climate	I-Application
model	I-Application
in	O
2002	O
,	O
and	O
developers	O
of	O
the	O
NCAR	O
Community	B-Application
Earth	I-Application
System	I-Application
Model	I-Application
(	O
CESM	B-Application
)	O
have	O
continued	O
to	O
contribute	O
to	O
CICE	B-Application
innovations	O
and	O
have	O
used	O
it	O
to	O
investigate	O
polar	O
variability	O
in	O
Earth	O
's	O
climate	O
system	O
.	O
</s>
<s>
The	O
United	O
States	O
Navy	O
began	O
using	O
CICE	B-Application
shortly	O
after	O
2000	O
for	O
polar	O
research	O
and	O
sea	O
ice	O
forecasting	O
and	O
it	O
continues	O
to	O
do	O
so	O
today	O
.	O
</s>
<s>
Since	O
2000	O
,	O
CICE	B-Application
development	O
or	O
coupling	O
to	O
oceanic	O
and	O
atmospheric	B-Application
models	I-Application
for	O
weather	O
and	O
climate	O
prediction	O
has	O
occurred	O
at	O
the	O
University	O
of	O
Reading	O
,	O
University	O
College	O
London	O
,	O
the	O
U.K.	O
Met	O
Office	O
Hadley	O
Centre	O
,	O
Environment	O
and	O
Climate	O
Change	O
Canada	O
,	O
the	O
Danish	O
Meteorological	O
Institute	O
,	O
the	O
Commonwealth	O
Science	O
and	O
Industrial	O
Research	O
Organisation	O
,	O
and	O
Beijing	O
Normal	O
University	O
,	O
among	O
other	O
institutions	O
.	O
</s>
<s>
As	O
a	O
result	O
of	O
model	O
development	O
in	O
the	O
global	O
community	O
of	O
CICE	B-Application
users	O
,	O
the	O
model	O
's	O
computer	O
code	O
now	O
includes	O
a	O
comprehensive	O
saline	O
ice	O
physics	O
and	O
biogeochemistry	O
library	O
that	O
incorporates	O
mushy-layer	O
thermodynamics	O
,	O
anisotropic	O
continuum	O
mechanics	O
,	O
Delta-Eddington	O
radiative	O
transfer	O
,	O
melt-pond	O
physics	O
and	O
land-fast	O
ice	O
.	O
</s>
<s>
CICE	B-Application
version	O
6	O
is	O
open-source	B-Application
software	I-Application
and	O
was	O
released	O
in	O
2018	O
on	O
GitHub	B-Application
.	O
</s>
<s>
There	O
are	O
two	O
main	O
physics	O
equations	O
solved	O
using	O
numerical	B-General_Concept
methods	I-General_Concept
in	O
CICE	B-Application
that	O
underpin	O
the	O
model	O
's	O
predictions	O
of	O
sea	O
ice	O
thickness	O
,	O
concentration	O
and	O
velocity	O
,	O
as	O
well	O
as	O
predictions	O
made	O
with	O
many	O
equations	O
not	O
shown	O
here	O
giving	O
,	O
for	O
example	O
,	O
surface	O
albedo	O
,	O
ice	O
salinity	O
,	O
snow	O
cover	O
,	O
divergence	B-Application
,	O
and	O
biogeochemical	O
cycles	O
.	O
</s>
<s>
Each	O
of	O
the	O
terms	O
require	O
information	O
about	O
the	O
ice	O
thickness	O
,	O
roughness	O
,	O
and	O
concentration	O
,	O
as	O
well	O
as	O
the	O
state	O
of	O
the	O
atmospheric	B-Application
and	O
oceanic	O
boundary	O
layers	O
.	O
</s>
<s>
Ice	O
mass	O
per	O
unit	O
area	O
is	O
determined	O
using	O
the	O
second	O
keystone	O
equation	O
in	O
CICE	B-Application
,	O
which	O
describes	O
evolution	O
of	O
the	O
sea	O
ice	O
thickness	O
distribution	O
for	O
different	O
thicknesses	O
spread	O
of	O
the	O
area	O
for	O
which	O
sea	O
ice	O
velocity	O
is	O
calculated	O
above	O
:	O
</s>
<s>
CICE	B-Application
version	O
6	O
is	O
coded	O
in	O
FORTRAN90	O
.	O
</s>
<s>
It	O
is	O
organized	O
into	O
a	O
dynamical	O
core	O
(	O
dycore	O
)	O
and	O
a	O
separate	O
column	O
physics	O
package	O
called	O
Icepack	O
,	O
which	O
is	O
maintained	O
as	O
a	O
CICE	B-Application
submodule	O
on	O
GitHub	B-Application
.	O
</s>
<s>
The	O
momentum	O
equation	O
and	O
thickness	O
advection	O
described	O
above	O
are	O
time-stepped	O
on	O
a	O
quadrilateral	B-Algorithm
Arakawa	O
B-grid	O
within	O
the	O
dynamical	O
core	O
,	O
while	O
Icepack	O
solves	O
diagnostic	O
and	O
prognostic	O
equations	O
necessary	O
for	O
calculating	O
radiation	O
physics	O
,	O
hydrology	O
,	O
thermodynamics	O
,	O
and	O
vertical	O
biogeochemistry	O
,	O
including	O
terms	O
necessary	O
to	O
calculate	O
,	O
,	O
,	O
,	O
and	O
defined	O
above	O
.	O
</s>
<s>
CICE	B-Application
can	O
be	O
run	O
independently	O
,	O
as	O
in	O
the	O
first	O
figure	O
on	O
this	O
page	O
,	O
but	O
is	O
frequently	O
coupled	O
with	O
earth	O
systems	O
models	O
through	O
an	O
external	O
flux	O
coupler	O
,	O
such	O
as	O
the	O
CESM	B-Application
Flux	O
Coupler	O
from	O
NCAR	O
for	O
which	O
results	O
are	O
shown	O
in	O
the	O
second	O
figure	O
for	O
the	O
CESM	B-Application
Large	O
Ensemble	O
.	O
</s>
