1320 
Circulation—continued 
prognosis, physical methods in, 806 
relationship between weather and, 809 
studies, Arctic, 942 
tropical, empirical laws governing, 861 
undulations in circumpolar vortex, 
i 555 
upper-level, effect on weather, 723 
zonal, at sea level, 555 
variation in speed, 560 
zonal indices, seasonal behavior, 555 
zonal wind-speed profile, 555 
Circumpolar vortex, jet stream of, 559 
undulations in, 555 
Cirrus, ice crystals in, 222 
ice nuclei in, 196 
City planning, and microclimatology, 
1001 
Clicks see Sferics 
Climate, air-mass description, 968 
difficulties of, 970 
as a dynamical problem, 972 
as a physical problem, 972 
basic requirements for discussion, 974 
during geological time, 1004 
during ice ages, 1004 
early ice ages, 1006 
Hocene, 1004 
geographic control, 1012 
Jurassic age, 1004 
mountain building and, 1013 
pluvial periods, 1006 
synthesis of weather, 967 
world, expression of, 967 
Climatic change, continental drift, 1012 
correlation with glacier changes, 1020 
dependent on external influences, 
theories, 1010 
due to terrestrial causes, theories, 1012 
during Christian era, 1008 
effect of changes in earth’s orbit, 1010 
effect of solar radiation on, 1010 
geological aspects, 1004 
historical aspects, 1004 
Palaeozoic ice age, 1014 
postglacial, 1007 
research needed, 1017 
role of carbon dioxide variations, 1015 
role of ocean currents in, 1014 
role of polar ice caps, 1014 
solar-topographie theory, 1016 
topographic theory of, 1016 
tree-ring indices, 1028 
voleanic dust and, 1015 
INDEX 
Climatology—continued 
aviation, demands of, 968 
Greenland, 961 
human comfort and health, 980, 1117 
human pathology and, 981 
use of synoptic maps in, 970 
Clothing design, applied climatology 
and, 983 
Cloud, and weather types, 1175; see also 
Clouds 
boundaries, upper, distribution with 
altitude, 44 
centers of electrification, effect on 
aircraft, 134 
classification, need for uniform prac- 
tice, 1165 
according to form, 1165 
convection, 694 
classes of, 1261 
cross sections, 1174 
data, synoptic, aid in forecasting, 1173 
droplet, accretion, 205 
evaporation of, 204 
growth by coalescence, 176 
growth formula, 169 
growth of, 169 
ice phase, 173 
liquid-water content, 171 
measurement, 171 
size, 1201 
and liquid water, 171 
distribution, 170 
by cloud types, 173 
in sea fog, 173 
distribution curves, 172 
in free atmosphere, 172 
measurement, 171 
edges, evaporation from, 200 
heat conduction from, 200 
elements, condensation on, 204 
effect of thermal processes on, 204 
electrical characteristics, 130 
heat exchange between air and, 199 
melting processes, 205 
sublimation on, 204 
environment mixing, 695 
formation, experimental, 1255 
applications to atmosphere, 1260 
comparison of phenomena in air 
and carbon dioxide, 1260 
Lord Rayleigh’s theories, 1256 
motion in unstable layers of air, 
1256, 1258 
nature of simple convection cell, 
Cloud—continued 
structure, relation to thunderstorm 
electricity, 687 
synoptics, historical summary, 1174 
-to-cloud lightning discharge, 139 
transformations, interpretation of 
observed trends in, 1168 
types, drop.size variations in various, 
Cloudiness, effect on ultraviolet radia- 
tion, 1119 
Clouds, 163, 1159 
albedo, 26 
altocumulus, and thunderstorm move- 
- ment, 1173 
altocumulus and rain, 1169 
altocumulus castellatus, and rain and 
thunderstorms, 1169 
altocumulus lenticularis, and wet 
weather, 1170 
citrecuanulus weather conditions with, 
classification of forms, assessement of 
adequacies, 1164 
assessment of inadequacies, 1164 
cirrus, movements, and temperature 
changes, 1172 
motion, use in forecasting cyclone 
movement, 1171 
speed, and storm speed, 1172 
velocities, and weather changes, 1172 
convective, dynamics of, 201 
slice method of analyzing, 201 
development of ice phase in, 194 
dirceuion of motion, use in forecasting, 
0 
double cirrus, weather associated with, 
drop-size distribution, 170 
effect on atmospheric radiation, 42 
effect on shape of sky, 61 
entrainment of air, 694 
formed outside space they occupy, 1162 
high-level, ice phase in, 196 
ice see Ice clouds 
in forecasting, research needed, 1176 
in short-term forecasting, 1167 
interior, heat conduction in, 200 
iridescent, 71 
liquid-water concentration, 1200 
liquid-water content, effect of eleva- 
tion, 698 
moapnatus, weather associated with, 
1169 
Climatic data, analysis of requirements 1255 
in various activities, 976 research needed, 1261 
Climatic Optimum, 382, 1007, 1021 Sutton’s theory of Bénard cells, 
Climatological analysis, for operational 1261 
medium-level, ice phase in, 196 
microorganisms in, 1109 
mixed, physics of, 192 
mixing processes and, 200 
planning, 980 
Climatological material, sources of, 977 
Climatological problems, Arctic, 952 
Climatology, agricultural, 980 
applied, 976 
and aerial mapping, 986 
and agricultural land usage, 987 
and aviation, 988 
and clothing design, 983 
and deterioration of materials, 985 
and flood water run-off, 987 
and forest fires, 988 
and housing design, 982 
and aero of ‘“‘weather goods,” 
and objective forecasting, 986 
and solar radiation, 984 
and wind for power production, 984 
classes of problems, 979 
data for, 977 
definition, 976 
frost hazard, 984 
historical note, 976 
list of topics, 990 
techniques, 981 
weather insurance, 981 
forms, classification, 1161 
genetical classification, 1162 
international classifications, 1161 
physical classifications, 1163 
radiational influences, 203 
indications of new developments, 1175 
of passing low, 1175 
mass, effect of elevation on, 698 
effect of humidity on, 698 
effect of temperature on, 698 
modification, artificial, relation to 
production of precipitation, 235 
by water, 230 
methods, 229 
with dry ice, 229 
with silver iodide, 230 
motions, as wind indicators, 1172 
observation, 1167 
Physics Project, 236 
experiments on stratus clouds, 236 
experiments with cumulus clouds, 
239 
properties, mixing on, 696 
radiation, 42 
seeding see Seeding, cloud 
size, aircraft measurement, 1228 
observed, application of diurnal cycle 
to, 1167 
of advection, 1163 
of convection, 1162 
of turbulence, 1163 
orographic, 1163 
physical classification, 1163 
physics of, 165 
point of convergence, use in forecast- 
ing, 1170 
proper to space they occupy, 1162 
radiation processes and, 43, 200 
reflection of solar radiation by, 26 
solar radiation absorption by, 21, 31 
supercooled, elimination by cloud 
seeding, 232 
factors controlling life cycle of, 227 
temperature lapse rate, effect of 
mixing, 696 
thermodynamic analysis, 697 
thermodynamics of, 199 
tropical cyclones, 890 
undulated sheet, weather associated 
with, 1169 
use in forecasting, 1167 
wind-shift line marked by, 1173 
