1324. 
Forecasting—continued 
short-range—continued 
pressure-change and other auxiliary 
charts, 749 
pressure charts, 749 
problem, 747 
processing observational data, 748 
prognostic chart preparation, 753 
radiosonde diagrams, 750 
research needed, 763 
snow-on-the-ground chart, 749 
statistical aids, 762 
steps in, 758 
nleps recommended by Petterssen, 
9 
surface prognostic chart, prepara- 
tion, 756, 769 
temperature, 761, 788 
temperature charts, 749 
thermodynamic diagrams, 748 
type studies, 750 
use of surface data, 749 
use of upper-air data, 750 
usefulness of various charts, 760 
usefulness of various techniques, 760 
verification, 762, 841 
weather prognosis, 760 
wind, 761, 791 
zonal index graph, 749 
short-term, clouds in, 1167 
solar control, 740 
statistical, research needed, 852 
statistical method, application, 849 
statistical techniques of extrapola- 
tion, 734 
storm sexed significance in cyclones, 
99 
bon (ide significance in cyclones, 
00 
synoptic cloud data as aid in, 1173 
synoptic cycle, 766 
Bynopelc techniques of extrapolation, 
35 
techniques, 731, 733 
analogues, 737 
extrapolation, potentialities, 737 
lag-correlation, 734 
linear extrapolation, 736 
need for standardization, 741 
performance, 732 
physical, 739 
present practice, 732 
synoptic extrapolation, 735 
thunderstorm, 690, 1170 
tools, 731 
tornadoes, 678, 792 
tropical cyclone movement, 897, 911 
uns tstaetory progress, reasons for, 
31 
upper-air map prognosis, 780 
use of clouds in, 1167 
use of microseisms in, 1312 
use of radar in, 1279 
use of sferics in, 1299 
use of stationary time series in, 850 
use of surface map in, 769 
vertical velocities as tool for, 645 
wave formation, 771 
weather see also Forecasting 
weather system movement, dynamical 
approach, 849 
statistical approach, 849 
weather-type approach, 835 
wind, 791 
Forecasts, accuracy of, 769 
area, 767 
chance, 846 
climatological, 846 
daily, extended, 733 
range, 733 
extension to longer periods, 811 
general, 767 
local, 767 
long-range, 733 
INDEX 
Forecasts—continued 
medium-range, analogue methods, 828 
combination of synoptics and statis- 
tics, 828 
persistence, 846 
Brest ton, contingency table for, 
short-range, 732 
time range, 732 
types, 732 
verification, 841 
Forest ates, and applied climatology, 
9 
Forest tundra, 953 
Forest-tundra ecotone, 953, 957 
Forestry, and microclimate, 1000 
Fork lightning, 141 
Formaldehyde, atmospheric, determin- 
ing, 1131 
Fragmentation nuclei, effect on snow 
formation, 226 
Free-electron density, 334 
Freeman wayee in tropical meteorology, 
870 
Freezing nuclei, 174, 192 
effect on snow formation, 224 
Frictional effects, dynamic forecasting 
and, 482 
Fringe region, 247 
Front, cold, radarscope photographs, 
1271 
equatorial, 865 
occluded, radar pictures, 1274 
warm, radar pictures, 1272 
Frontal occlusion, 778 
Frontal phenomena, intertropical, 882 
intertropical convergence zone, 882 
meridional, 882 
tropical, 882 
Frontal precipitation, radarscope photo- 
graphs, 1271 
Frontal strip, 770 
Frontal theory, modifications, 867 
tropical meteorology, 866 
Frontogenesis, 432, 590, 770 
profile through, 593 
Frontolysis, 780 
Fronts, modifications, forecasting, 779 
Frost, amorphous, 207 
crystalline, 207, see also Crystalline 
frost 
-point determination, in lower strato- 
sphere, 313 
-point hygrometer, design of, 312 
protection, applied microclimatology 
and, 999 
window see Window frost 
Fulchronograph, in measurement of 
lightning characteristics, 142, 
150 
G 
Gas chemistry, general principles, 263 
Gas diffusion in atmosphere see Diffusion 
Gas particles, kinetic energy of, 268 
Gas reactions, condensation nuclei for- 
mation from, 186 
Gases, atmospheric, escape, 246 
General circulation, see Circulation, 
general 
Geographic cycles, 1012 
Geographical location, effect on land and 
sea breezes, 658 
Geohydrology, 1048 
Geological temperature variations, 1017 
Geomagnetic lunar tide, 521 
Geostrophic approximation, 
forecasting and, 470 
Geostrophic current, inertial oscilla- 
tions of, 440 
Geostrophic motion, general conditions 
for stability of, 437 
law of, 435 
stability of, 434 
dynamic 
Geostrophic zonal wind speed, 555 
Gerdien aspirator, 147 
Gewitter, electrical characteristics, 128 
Glacial periods, climate during, 1004 
Glacial sequence, Quaternary Ice Age, 
1005 
Glaciation, effect of solar radiation 
variation on, 1010 
maximum, climatic conditions in, 381 
Glacier research, climatic implications, 
1019 
Glaciers, as climatic indicators, 1019 
research needed, 1022 
changes, causes of, 1019 
correlation with climatic change, 
1020 
nature of, 1019 
since beginning of Christian era, 1020 
within Pleistocene epoch, 1021 
within recorded time, 1020 
Wisconsin maximum, 1020 
Glare, effect on vision, 1119 
Glory, 71 
Gondwanaland, 1014 
Gowan, calculations of equilibrium tem- 
perature in ozone layer, 298 
Gram-atom, 263 
Gram-molecule, 263 
Granules, 379 
Graupel formation, 205 
Gravitational instability, in fluid mo- 
tion, 467 
Green flash, 65 
Green segment, 65 
Greenland, climatological problems, 961 
glacial anticyclone, 961 
Hobbs’ theory, 961 
ice cap, alimentation, 962 
radial wind system, 962 
wind and weather régime, 961 
Grinders, see Sferics 
Grossturbulenz, 502 
Grosswetter, 814 
consecutive weather anomalies, cor- 
relations between, 817 
cosmic influences on, 819 
effect of ice conditions, 815 
effect of long waves on, 817 
effect of moon, 819 
effect of ocean currents, 815 
effect of periodic fluctuations of 
climate, 817 
effect of planets, 819 
effect of polar motion, 816 
effect of pressure waves, 816 
effect of solar radiation, 820 
effect of sunspot cycles, 819 
effect of volcanic eruptions, 815 
existence of, 814 
governing complexes, 815 
morphology, 822 
problem of rhythms, 816 
terrestrial influences, 815 
Grosswetterlagen, 803 
annual variation, 826 
European types, 825 
Northern Hemisphere types, 826 
types of, 825 ; 
Ground, radon exhalation from, 158 _ 
Ground inversions, effect on effective 
terrestrial radiation, 39 f 
Ground reflection, effect on Arago point, 
82 
effect on skylight polarization, 85 
Ground state, 263 
Ground wires, use in lightning protec- 
tion, 142 
Grounding, of electrostatic instruments, 
145 
H 
Hail, growth, physies of, 178 
Hail insurance, 981 
