1322 
Diffusion—continued 
in upper atmosphere, 320 
laboratory investigations, 1252 
matter, in nonadiabatic gradients, 507 
maximum mixture, 324 
maximum separation, 324 
molecular, 320 
of particulate matter, 326 
partial separation, 324 
research needed, 332 
small-seale, 503 
theory of, 320, 503 
three-dimensional, 329, 504 
three-dimensional, examples of, 330 
general causes, 329 
time required for establishing equilib- 
rium, 328 
two-dimensional, 503 
Diffusion coefficients, observed, 321 
Diffusion diagram, 322 
Diffusion equilibrium, 320 
Diffusion processes, effect of representa- 
tive wind field on, 330 
Diffusion theory, Richardson’s, 505 
Diffusion velocity, in maximum mixture, 
324 
vector of, 320 
Dissociation energy, 263 
Dissociation potential, 263, 269 
Dissociative recombination, 270 
Disturbances, extratropical, aerology of, 
599; see Cyclones 
Divergence, and pressure change, 643 
direct measurement, 639 
distribution of, theory of, 642 
effects of, 648 
influence of scale on, 639 
large-scale, distribution of, 641 
Dobson spectrophotometer, 276 
Doldrums, air motion, 862 
Droplet size, electric field and, 133 
importance in separation of free elec- 
trical charges, 132 
Dry ice, cloud modification by, 229 
Dust, albedo, 26 
effect in scattering solar radiation, 23 
volcanic, effect on skylight polariza- 
tion, 79 
Dust counter, Aitken, 165 
Dust devils, 679 
Dust particles, measurement, 148 
Dynamic forecasting see Forecasting, 
dynamic 
Dynamic instability, see also Hydro- 
dynamic instability, 584 
E 
Eady, baroclinic wave studies, 459 
Earth, albedo, 27, 31 
meteorological parameters, 392 
shadow, 73 
surface, albedo of, 27 
heat exchange at, 50 
Ebert ion counter, 147 
Eddy diffusion, 321, 501 
horizontal coefficients, 330 
in microclimate, 996 
Electric charge separation, 116 
Electric current, air-earth, 113 
density, over thunderheads, 114 
Electric field, and droplet size, 133 
atmosphere, measurement, 148 
effect on electrical conductivity of air, 
of atmosphere in fair weather, 107 
Electrical apparatus, protection against 
lightning, 142 
Electrical charges, by adhesion, 1134 
free, importance of droplet size in, 132 
on individual droplets, 130 
observed on precipitation, 128 
separation of, 132 
Electrical conductivity, of air, 102 
variations, 103 
INDEX 
Hlectrical potential gradient of air, 108 
Electrical properties of snow, 227 
Electricity, atmospheric, 128 
instruments for measuring, 144 
dielectric materials used in, 144 
measurement, 150 
measuring equipment, auxiliary, 144 
methods for measurement of, 144 
outstanding problems, 118 
present-day research, 150 
space charge, measurement of, 149 
supply current and thunderstorms, 
universal aspects, 101 
vertical current, measurement, 149 
precipitation, 128 
in cloud elements, 130 
in continuous rain, 129 
in electrical storm rain, 129 
in snow, 129 
in squall rain, 129 
in thunderstorms, 129 
practical problems, 128 
thunderstorm, cloud structure and, 687 
current, 150 
field, 150 
investigations of, 150 
lightning discharges, 150 
precipitation charge, 150 
radio interference, 150 
Electrification, of aircraft flying through 
precipitation, 133 
Electrode effect, 108 
Electrograms, 109 
Electromagnetic cgs system, 144 
Electromagnetic fields, forced diffusion 
and, 323 
Electrometer, circuits, 144 
types, 144 
use in measuring atmospheric elec- 
tricity, 144 
Electron affinity, 263 
Electron volt, 264 
Electronic configuration, 263 
Electrostatic egs system, 144 
Electrostatic charges, of condensation 
nuclei, 187 
Electrostatic induction, discharge, meas- 
urement, 148 
Elsasser’s diagram, 37 
Emanometers, types, 156 
Emanometrical measurements, 
diagram for, 156 
Emanometry, 155 
correction of alpha rays, 156 
effect of atmospheric pressure and 
temperature, 156 
saturation correction, 156 
time correction, 156 
Emission-spectral evidence, upper at- 
mosphere composition, 271 
Emission spectrum, 264 
Emitting layers, upper 
heights of, 271 
Empire State Building, lightning dis- 
charges to, 139 
Energy, concept of, 483 
in latent form of water vapor, exchange 
rate of, 1061 
kinetic, law of, 484 
potential, conversion to kinetic en- 
ergy, 458 
total, global balance, 572 
basic equations, 572 ; 
transmission of, by means of finite 
disturbances in inversion height, 
429 
Energy change, 483 
Energy equations, 483 
applications of, 489 
basic, 486 
for averaged properties, 488 
in barotropic atmosphere, 462 
stress values, 490 
cireuit 
atmosphere, 
Energy laws, basic, 485 
Energy levels, 263 
Energy principles, application to general 
circulation, 568 
Energy transformations, in the atmos- 
phere, 490 
over oceans, 1057 
Energy units, 264 
Entrainment of air by clouds, 202, 695 
in thunderstorms, 683 
Eocene age, climate, 1004 
Equations, energy see Energy equations 
ange ee use in dynamic forecasting, 
480 
Equatorial front, 865 
Equatorial meteorology, 381 
air masses, 881 
equations of motion, 883 
forecasting, 885 
frontal phenomena, 882 
Eseape, cone of, 247 
Eulerian equations, 405 
use in dynamic forecasting, 480 
Eulerian system, perturbation equa- 
tions, 407 
Evaporation at cloud edges, 200 
Evaporation, at sea, direct measure- 
ments, 1071 
history, 1071 
detailed study, 505 
determining, 1049 
effect on supercooled clouds, 228 
factor in hydrology, 1049 
from oceans, 1071 
Bowen ratio, 1058, 1073 
computed from energy considera- 
tions, 1073 
computed from meteorological ele- 
ments, 1074 
theoretical considerations, 1075 
determined by extrapolations of 
values from land, 1071 
energy available for, 1073 
from rough surfaces, theoretical con- 
siderations, 1077 
of cloud droplets, 204 
Evaporation factor, as function of wind 
velocity, 1078 
from climatic data, 1079 
from meteorological observations, 1078 
Hive rao rates, at various latitudes, 
1072 
Eve number, 146 
Excitation by collision, 267 
Excitation energies, 263 7 
Excitation potentials, 263 
Excited states, 263 
Hxosphere, 247 y 
Expansion wave, and pressure jump, 
interaction between, 428 
storm, 432 
Exponential atmosphere, monochro- 
matic absorption, 265 
Extratropical cyclones see Cyclones, 
extratropical . 
Eye, human, light-distinguishing prop- 
erties, 93 
visual range, calculation, 93 
hurricane, dynamical aspects, 907 
thermal structure, 905 
tropical cyclones, 891 
F 
Faculae, 379 
Fallstreifen, appearance of, 192 
trails, shape, 196 
Fata Morgana, 66 
Feather-like frost, 207 
“Fido,” 178 
Filter method, 149 
Fire-danger meters, 988 
Fire day, 988 
Fire weather, 988 
Fireballs, 356 
