56 MALKUS AND RONNE 
Tech. and Woods Hole Ocean. Inst., 11, 1, 82 
pp., 1949. 
Riext, H., W.S. Gray, J.S. Markus, anp C. Ronn, 
Cloud structure and distributions over the 
tropical Pacific, pt. I, unpublished manuscript, 
WHOI Ref. No. 58-62, 1959. 
Stommer, H., Entrainment of air into a Cumulus 
cloud, J. Met., 4, 91-94, 1947. 
Appendix 
Tropical Whole Sky Code 
Joanne S. Mauxus anp Hersert Rineu 
This code is for use primarily in coding aerial 
photographs (or visual observations) over the 
open seas in the tropies far from land masses. 
Categories 0-4 denote undisturbed trade-wind 
skies. Categories 5-9 cover weak or trade-wind 
type disturbances, while categories 10-16 relate 
to strong disturbances (deep easterly waves, 
equatorial trough disturbances or convergence, 
through typhoons). The letters (to be placed 
after the appropriate numbers) permit some 
further refinements or sub-specifications. 
TRADE-WIND SKIES 
O No clouds at all, or a few suppressed, or 
small numbers of very suppressed Cumulus. Up- 
per cloud 1/10 or less. 
1 Inversion-dominated: trade Cumulus spread- 
ing out into Stratocumulus, definite signs of 
stratiform but total sky cover less than about 
one-half. 
2 Extensive Stratocumulus decks, more than 
about one-half total sky cover. 
3 Average trade Cumulus sky, no particular 
organization into lines. No significant upper 
clouds. No marked shear. Tops 8000-10,000 or 
less, precipitation unlikely. 
4 Average trade Cumulus sky, but with 
marked organization into rows or lines. No sig- 
nificant upper clouds. No marked shear. Tops 
8000-10,000 or less. Precipitation unlikely. 
5 Average trade Cumulus sky with upper 
sheet clouds up to broken. No marked organiza- 
tion or shear. No precipitation. 
6 Marked concentration of convection, rather 
large convection clouds (not Cumulonimbus) in 
view, with extensive clear or almost clear areas. 
Upper sheets to broken may be present. 
7 Suppressed trade Cumulus. sky with upper 
sheets broken or overcast but not precipitating. 
No marked shear or organization in Cumulus. 
8 Above average Cumulus activity, high tops, 
occasional Cumulus congestus. Showers suspected 
or seen. Upper cloudiness less than broken. No 
marked shear or organization of Cumulus. 
9 Above average Cumulus activity, high tops, 
occasional Cumulus congestus. Showers suspected 
or seen. Upper cloudiness broken to overcast. No 
marked shear or organization. 
10 Occasional Cumulonimbus, no obvious or- 
ganization, no significant or extensive independ- 
ent upper sheet clouds. Indicate component of 
shear in plane of film. 
11 Rows or suspected organization of Cumu- 
lonimbus, no extensive or significant independ- 
ent upper clouds. Indicate component of shear 
in plane of film. 
12 Cumulonimbus and partial coverage of in- 
dependent upper sheet clouds. Cirrus, Altostratus 
and/or Altocumulus. 
13 Substantial upper cloud coverage, sup- 
pressed convection over wide clear areas, except 
some Cumulonimbus visible. Precipitation from 
upper clouds absent or unlikely. 
14 Rain from upper sheets (overcast or al- 
most overcast) Cumulonimbus indistinct, picture 
dark. 
15 Rain from upper overcast, Cumulonimbus 
still suspected but not clearly visible, picture 
dark and disturbed. 
16 Upper overcast raining, no Cumulonimbus 
seen or suspected, suppressed low convective ac- 
tivity; picture dark and disturbed. 
Posrscripts (PRIMARILY FOR 
TRADE-WIND SKIES) 
o Marked organization into rows or lines. 
s Shear obvious; indicate component in plane 
of film. 
ce Apply to 1 or 2 if Cumulus tops are seen 
poking through the Stratus. 
d Distant disturbance—evident from high 
clouds low on horizon. 
— Weaker, more suppressed or less develop- 
ment than normal for category. 
