164°W 172°W 
KEY TO ICE SYMBOLS 
180° 
[THICKNESS AND SNOW. COVER] 
COVERAGE (CONCENTRATION) AGE 
A an = 
[Jee trae % dominant, % secondary Thickness; 5 where n= feet and inches 
Si=Slush W=Winter ice 
Y=sYoung ice Pl==Polar ice 
Examples; 
<0.1 (open water) 
a Arh 
Gow, 40PI Woo” 
KS) thew 0.9 (close ice) Pa 
Puddles: inant it 
FERRY 10 constidated or tst coy coninoalianoun 
in tenths unless 
COVERAGE BY SIZE 
frozen or rotten 
F=Frozen R=Rotten 
Cn 
Me Mp My 
=tenths of slush, brash, and block weer Crack S——= Lead 
n,=tenths of small and medium floes oO Polynya 
n=tenths of giant-floes and field 
A Icebergs—many (>20) 
—— Observed A -[cebergs—few (<20) 
——— Estimated @ Bergy bits and growlers (>20) 
© © © Limit of observed data Bergy bits and growlers (<20) 
ae sisisis 
“nc DO 
n=depth to nearest inch 
C=ice uniformly snow covered 
D=snow cover in drifts 
O==no snow cover present 
AA Rafted ice 
NA Ridged ice 
OOO Hummocks 
Extent: H=very extensive 
L=few present 
When no entry appears beneath 
symbol extent is moderate 
Examples: 
ws very extensive ridging 
AA =moderate rafting 
000 — 
ales =few hummocks 
172°E 
164°E 
156°E 
Gn 
O62 BOWZ20PI 
164°E 
FIGURE 71. RESULTS OF AERIAL ICE RECONNAISSANCE, ROSS SEA 
101 
