Forcing
Mechanisms
of
the

 Ross
Ice
Shelf
Airstream
 Melissa
A.
Nigro
 John
J.
Cassano
 University
of
Colorado
and
CIRES
 Boulder,
Colorado Ross
Ice
Shelf
Airstream
 A
dominant
stream
of
air
flowing
northward
from
the
interior
of
conDnent
across
 the
western
to
central
RIS
to
the
Ross
Sea
(Seefeldt
and
Cassano,
2012)
 RAS
Forcing:
   KatabaDc
winds
   Barrier
winds
   SynopDc
forcing
 Parish
et
al.
(2006),
Parish
and
Bromwich
(1986),
Parish
and
Bromwich
(1998),
Seefeldt
and
Cassano
(2012)
 2 Barrier
Winds
 CF
 PG
 Mountains
 O’Connor
et
al.
(1994),
Parish
et
al.
(2006),
Seefeldt
et
al.
(2007),
Steinhoff
et
al.
(2009)
 3 What
about
other
dynamics?
 4 Agenda
  
Self
Organizing
Maps
(SOM)
  
Ross
Ice
Shelf
Airstream
Pa[erns
  
Forcing
of
the
Ross
Ice
Shelf
Airstream
  
Conclusions
and
Future
Work Self
Organizing
Maps
 Technique
   Neural
network
algorithm
   Unsupervised,
iteraDve
learning
process
   IdenDfies
user
specified
number
of
pa[erns
within
a
   dataset
 Training
   AMPS‐WRF
15
km
   3
hourly
output
from
Oct
2008
–
Sept
2010
   Trained
on
the
u
and
v
component
of
the
10
m
winds
   Trained
with
10
m
winds
of
RAS
pa[erns
   6 SOM
Pa[erns SOM
of
RAS
Pa[erns
 8 SOM
TransiDons
 9 Weather
Pa[erns
 10
m
winds:
 Sea
Level
Pressure
Anomalies:
 Pressure
Gradient
Force:
 10