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Inclex A Acid rain, role of lightning in generation of, 76, 91 Acoustic waves, 52-56, 58-59 Aerosols dispersion, 154, 157 effect on ion depletion, 152, 160 from volcanic eruptions, 168-170, 175, 181, 187 in lower atmosphere, 168, 181 in mesosphere, 188 in upper troposphere, 168 nature of, 152-153 stratospheric, morphology of, 168 Air-earth current, 176-177, 180, 206, 215- 216 Aircraft downdraft threat to, 84, 93 gust front hazard to, 86 lightning strikes to, 42, 44, 61, 64-65, 69 protection of from lightning, 61 Arctic haze events, 168 Atmosphere electrical structure of, 6-8, 159-162, 194, 222-223 nitrogen fixation in, 1, 70-75 overturning in, 82-84 prebiological, trace gases in, 75-76 radioactive gases in, 150 refractive effects of, 55 role of lightning in chemistry of, 30, 70- 77, 91 study recommendations on, 16-20 thermal structure during thunderstorms, 55-56 259 see also Lower atmosphere; Middle atmo- sphere; Upper atmosphere Atmospheric-electric fog effect, 153, 158, 164 Auroral oval, 19~197, 203 B Blunt-probe technique, 189-190 Broadband antenna system, lightning signa- ture measurement with, 33 Buildings, lightning protection for, 66-67 C Canada, lightning detection networks in, 28- 29, 62 Carnegie curve, 155, 216, 226-227 Cloud scale charge separators, 4-5, 114 Clouds acid generation in, 76, 91 acoustic wave scattering by, 53'54 all-water, 131 altostratus, 173 anvil, 107 artificial chaff seeding of, 141 breakup charging in, 118, 126, 128-129 charging mechanisms in, 4-6, 13, 114- 130, 132-139, 141-142 chemical effects of lightning on, 30, 70-77, 91 cirrus, 173 convective charging, 114-129, 132, 142, 144 cumulonimbus, 4, 207 cumulus congestus, 136 diffusion charging in, 5, 115-116, 128-129 drift charging in, 5, 116-117, 125-126, 128-129 drop charging in, 120 electrical development of, 131-145 electrified, 91, 127 inductive charging in, 119-121, 127-129 133-134, 137-139, 141-142 interface charging in, 121-124, 128-129 isolated cirrus, 131 maritime, 142 mesocyclone wall, 42 noctilucent, 183, 188 noninductive charging in, 134-135, 138 139, 141, 143 particle charge of, 100, 105, 115-129, 140 selective ion charging in, 117-118, 126, 128-129, 135-137 slab, 141 stratocumulus, 124, 136 stratus, 131, 173 thermoelectric charging in, 121, 128-129, 134 thunder inside, 54 turrets, 127 warm, 99, 126, 129, 142 see also Cumulus clouds; Thunderclouds Communication cables, telluric current in- teraction with, 243-245 Communications, use of waveguide in earth's crust for, 249 Condensation, relative to air motion, 84 Conductivity aerosol density effect on, 173

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260 atmospheric, 170-176, 178-179, 188-192, 197, 206-207 Hall, 214 ionic, 156 Pedersen, 214 see also Telluric currents Contact potentials, 121-124, 135, 142 Convection as a cloud-scale separator, 114 charge currents for, 102 in thunderstorms, 4, 81-82, 84-85, 95, 97, 99, 102, 109-110 role in cloud particle growth, 132-133 theories of electrification, 110 see also Downdrafts; Updrafts Corona charge, 5, 92, 103-104, 110, 127 currents, 94-95, 119, 136, 211 discharge, 1, 93, 101, 133, 139, 141, 178, 210 see also Hydrogen geocorona Corrosion, telluric current enhancement of, 247 Cosmic radiation atmospheric ionization by, 6, 150, 164, 167, 180, 184, 189-190, 206, 213, 215 latitudinal variation in, 167 Cumulus clouds, charge separation in, 114- 129 Currents, see Air-earth current; Corona, cur- rent; Earth currents; Lightning cur- rents; Maxwell currents; Telluric cur- rents Cyclones, positive CG lightning associated with, 43 D Deep-earth studies, use of telluric currents for, 248 Defense Meteorological Satellite Program, 23-25 Differential reflectivity polarization radar technique, 111 Diurnal variation, 6, 155-157, 177, 207, 210, 213, 216, 226, 233 Doppler radar, thunderstorm observations with, 14, 94, 100, 103, 109 Downdrafts role in thunderstorms, 84-85, 87, 93, 127, 136, 142, 207 threat to aircraft, 84, 93 E Earth currents, 232; see also Telluric currents East Coast Network, 33, 62-63 E1 Chichon, aerosols from eruption of, 9, 169-170, 175 Electric field meters, balloonborne, 93 Electric fields anthropogenic influences on, 178-179 INDEX characteristics of, 217 density, 156 fluctuations caused by turbulence, 154 Grounding, 67 interactions with upper atmosphere, 203 204 lower atmospheric, 176-181 mapping of, 191 measurements, 94-95 over oceans, 210-211 patterns, 199-201 produced by thunderstorms, 92 upper atmospheric sources of, 195-205 vertical, 178, 191 see also Electromagnetic fields Electrical processes, techniques for evaluat ing, 12-14 Electrical relaxation time, 217 Electricity, atmospheric variations, 155-159 Electrification cloud stage in, 5, 115-117, 124-125, 129 convective theories of, 99, 110 experiments to test ideas about, 103 hail stage in, 5, 120-124, 126-129 precipitation theories of, 97, 100-102, 110 rain stage in, 5, 117-120, 125-126 Electrode effect, 153, 158, 160-161, 164 Electromagnetic fields, lightning-radiated, 30, 32-34, 36, 64 Electromagnetic signals, from space, detec tion of, 247 Electronic equipment, lightning protection for, 66-67 End of storm oscillation, 93, 109 Equalization layer, 7, 176, 190 Equator, ionization rate at, 167 Equatorial electrojet, 201 F Fair-weather electrical field, 1, 6, 14, 162, 191-192, 215-216, 234 Faraday law of magnetic induction, 197 Fires, caused by lightning, 30, 45; see also Forest fires Florida lightning flash density in, 27 thunderstorm characteristics in, 95-96, 99 Fog, conductivity in, 136, 158, 177 Forbush decreases, 8, 167, 172, 184, 192 Forest fires, detection of, 15, 62 Freezing potentials, 121-124, 134-135 G Geomagnetic depth sounding, 247-248 Gerdien condenser technique, 171, 173-175, 189 Global electric circuit, 6-8, 11, 30, 92, 114, 149, 153, 156, 162, 166, 176, 178, 192, 206-231 Global electrostatic potential, 200-201 Greenhouse effect, 81-82 H Hail growth and trajectory of, 85-86, 88, 120, 127 soft, 120-121, 123-124 wet, 121 HCN, atmospheric production of, 75-76 High-frequency radiation, lightning pro- cesses producing, 36 Hydrogen geocorona, 185, 190 Hydrometeors, 105 I Inductive theory, 102-103 Infrasound, 105 Interplanetary magnetic field, 195, 198, 201, 203 Ion physics, research need in, 17, 163 Ionization from bursting of water films, 151, 159 from cosmic rays, 6, 150, 164, 180, 189 190, 213 from electrical discharges, 150 in planetary boundary layer, 150-151 of nitric oxide, 189 rate over oceans, 151, 164 solar extreme ultraviolet radiation, 208, 213-214 vertical variation of, 150-151 Ionosphere characteristics of, 10-11, 195-197 conductivity of, 197, 206 dynamo region, 11, 197-202, 224 electric field effects on, 203 negative effects of magnetic fluctuations in, 204 potential variations, 155-156 potential, 216 Ions attachment to aerosol particles, 152-153, 188 depletion of, 152, 160 photodetachment of, 188 properties of, 151-152 J Japan, winter thunderstorms in, 41-43, 45, 96 Junge layer, 168 Jupiter lightning on, 39 trace gases in atmosphere of, 75

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INDEX K L Kennedy Space Center, lightning activity at, 2, 15, 27 Laboratory simulation of thunderstorm elec- trification process, 90, 127; see also Models/modeling Langmuir Laboratory for Atmospheric Re- search, 90 Lidar observations of atmospheric aerosols, 168 Lightning acoustic radiations from, 46-60; see also Acoustic waves; Thunder anomalous triggers, 37; see also Lightning, triggered attachment process, 31-34, 68-69 benefits from, 30 breakdown processes, 31, 33-34, 47-49, 92 charge center altitude, 96 charge transfer, 42, 44, 62, 64, 66 chemical effects of, 30, 70-77, 91 cloud-to-ground, 2, 25, 27-28, 30-33, 41 45, 48, 64, 71, 73, 92-93, 96, 102, 103, 105-107, 129, 208 clouds types having, 131 damage mechanisms of, 62-68 dawn and dusk activity, 23-25, 27, 212 deaths and damage from, 1-2, 15, 23, 30, 41, 61-62, 66-67 detection networks/systems, 12-13, 15, 28-29, 33, 41-43, 61-63, 105-106, 228 effect on precipitation, 104-105, 107 effect on storm charge, 101 electric field change in, 42-45, 92 electromagnetic fields radiated by, 30, 32 34, 36, 64 evolution in a thunderstorm, 107-109 global distribution of, 13, 23-25, 212 global energy dissipation by, 73-74, 76 ground observations of, 25, 27-29 initiation in storms, 2, 105, 129, 137, 142 143 instrumentation/techniques for studying, 30-31, 41, 92 intracloud, 25, 27-28, 30, 36, 92, 94-96, 105-107, 129 laboratory simulation of, 49, 107 latitudinal variation of, 23-25, 26-28, 82, 131 leaders, 2-4, 31-33, 36 maps, 62-63 measurements of, 41, 48-50, 95 midnight activity, 25 modification of storm electrification by, 104-107 nitrogen oxide production by, 71-76 occurrence rate over land, 131 on Jupiter, Venus, and Saturn, 4, 39 261 over seawater, 34-35 path length, 2, 30 phenomenology, 23-29, 61-62 physics of, 15, 30-40, 61-62 positive, 2, 15, 31-40, 42-44, 64-65, 69 precipitation and, 94, 104-105, 107, 142 prevention, 141 protection systems/techniques, 4, 32, 35 36, 61-69 radio source locations in, 36-37 rainfall relationship to, 27, 42, 54; see also Precipitation research accomplishments, 32-39, 61-69 research needs, 17, 39, 45, 68-69, 76 return stroke, 3, 31-36, 38, 41, 43-47, 49, 62 role in evolution of life, 76 satellite observations of, 23-24, 74, 228 seasonal variation of, 23-28, 41-44 signatures, 33 strikes to aircraft, 42, 44, 61, 64-65j 69 striking distance, 32 striking process in, 2-3, 32-34 time domain fields, 32-36 trace gases produced by, 76 triggered, 13, 37-39, 41-45 vertical wind shear correlation with, 42 warm-cloud, 99, 126, 129 whistlers, 30 Lightning channels acoustic reconstruction of, 57-58 development, 30 energy of, 3, 30, 50, 53, 56-57, 74, 76 formation of individual pulses from, 51 propagation effects of acoustic pulses from, 51-57 spark, 49, 51 temperature, 46-47, 50, 70-72 tortuosity, 48-51, 57 Lightning currents continuing, duration of, 44, 107 diversion of, 66 measurement, 32-36, 43, 46, 48-49 peak, 3, 30, 34, 41, 45-46, 62, 64 rise times, 4, 15, 35 Lightning flash density, 25, 27, 61-62 negative, processes of, 31-40, 64-65 rates, 2, 23-29, 228 Lower atmosphere aerosols in, 168, 181 electric fields in, 176-181 electrical coupling between upper atmo- sphere and, 224-227 electrical structure of, 166-182; see also Lower stratosphere; Troposphere ion production in, 167 Lower positive charge centers, 92 Lower stratosphere conductivity in, 170-176 electrical structure of, 8, 166-167 ion mobility in, 170-176 small ion concentration in, 170-176 Lower troposphere, conductivity variations in, 178-179 M Magnetic direction finders, lightning moni- toring by, 28-29, 33 Magneto-tellurics, 247 Magnetohydrodynamic approximation, 196- 198 Magnetosphere Alfven layer, 224 characteristics of, 10-12, 195-196, 225- 226 dynamo region, 11, 198-199, 202, 224 openings in, 198 plasma convection, 198-199 study of, 30 Magnetospheric tail, 198-199, 204 Mapping electric fields, 191-192 Mass spectrometric analyses, atmospheric, 175, 185-189 Maxwell currents, 5, 104, 138, 157, 162, 209-210, 222 Measurements air-earth current density, 176-177, 181 balloonborne, 93, 109, 166, 171, 174-175, 227 conductivity, 171 electric field, 94-95, 105 in-cloud, 105 ion density, 174-175 lightning current, 32-36, 43, 46, 48 mass spectrometric, 185-189 of atmospheric-electrical variables, 158 of current flowing from thunderstorm areas, 207 of electric field, 12, 192 of global-scale phenomena, 152 of ionospheric potential, 164, 228 of lightning, 62-63 of magnetospheric convection electric fields, 227 of planetary boundary layer, 149 of positive-ion composition in mesosphere, 185-186, 188 of thunderstorms, 93 particle velocity, 104-105 thunder, 56-59 Mesocyclones in thunderstorms, 85 Mesosphere aerosol content of, 188 dust particles in, 188 electric fields in, 192 ionization sources in, 6, 9, 184, 189-190, 213 nitric oxide concentration in, 9, 184, 213 ozone in, 190 positive ion concentration in, 185-186 temperature characteristics of, 183 Meteor-ablation particles, 188 Microscale charge separators, 4-5, 114-124

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262 Middle atmosphere aerosol role in, 183 atmospheric constituents of, 183 conductivity of, 188-192 electric fields in, 191-192 electrical structure of, 9-10, 183-194 ion chemistry in, 185-188 ionization sources in, 184-185, 192 negative ion composition of, 186 Models/modeling electrical structure of planetary boundary layer, 159-162, 222-223 general circulation, 223 improvements needed in, 222, 228-229 of convection currents, 161 of electrical development of clouds, 131- 145 of electrode effect, 160-161 of global atmospheric electricity, 217-224 of ion composition of middle atmosphere, 187-188 of planetary boundary layer, 218 of telluric currents, 233 of thunder, 51, 53-57 of thunderstorms, 207-210, 223 one-dimensional, 138-140, 159 parallel plate, 137 regional, 223-224 three-dimensional, 142-143 turbulence, 160 two-dimensional, 140-142 Mount San Salvatore, lightning studies at, 41, 43 N New Mexico, thunderstorm characteristics in, 95-96, 99 Nitrogen fixation, 1, 70-75 North America, lightning location networks in, 28-29 Nuclear power plants, ionization from, 150 o Oceans electric field over, 210-211 ionization rate over, 151, 164 Oklahoma analysis of tornadic storms in, 43 positive CG lightning in, 43-44 Oscilloscope, lightning signature measure- ment with, 33 Ozone in mesosphere, 190 p Pipelines, telluric current interaction with, 246 Planetary boundary layer atmospheric electricity in, 149-165 convection currents in, 161-162 INDEX effect of global electric circuit on, 153, 218, 222 effect on fair-weather electrical circuit, 162 ion physics and balance in, 163-164 ionization in, 8, 150-151 meteorological structure of, 159-160 research needs and applications, 162-164 turbulence, 8, 149-150, 153, 157 Point discharge, 92 Polar cap absorption, 184 Pollution, conductivity or columnar resis- tance as monitors of, 163-164 Power lines/systems lightning protection for, 62, 67 telluric current interaction with, 245-246 Precipitation charge carried by, 93, 100-103, 114, 126, 140 convective, 84 effect of lightning on, 94, 104-105, 107, 142 electric currents for, 102 modeling growth of, 143 relative to air motion, 84 theories of electrification, 97, 100-102, 110 Pulsations, 203 R Radiation, see Cosmic radiation; Radioac- tive gases; Radioactivity Radiation belts, atmospheric ionization by, 185 Radio interferometers, lightning observation with, 36-37 Radioactive gases in planetary boundary layer, 150 Radioactivity, ground, atmospheric ioniza- tion by, 150, 172, 213 Railways, telluric current interaction with, 246-247 Rainfall from electrified clouds, 91 relationship to lightning flash rates, 27, 42, 45; see also Precipitation Riming, 99, 120-121, 123, 127-129, 135, 139 Rockets conductivity measurements with, 189 electric field measurement with, 192 lightning triggered by, 37-39 mass spectrometric analysis using, 185 Rocky Mountains, thunderstorms over, 42- 43, 45 S Satellites lightning observation by, 13, 23-25 observations of magnetospheric convection patterns, 224 optical detectors in, 23-25, 74 radio detectors in, 25 Schumann resonances, 209 Snowstorms, electrification in, 99 Solar activity, atmospheric ionization by, 167, 171-172, 184 Solar flares, 196 Solar Lyman-alpha radiation, 9, 184-185, 189-190 Solar proton events, 9, 167, 179-180, 184, 191-192 Solar wind, 195, 197-202 Sonde, ion density, 174 Space charge, 153-154, 163, 178 Storms convective, 95-97, 99, 103 detection of downbursts in, 93 magnetic, 184, 202-204, 213, 226, 244- 246 studies of, 58 tornadic, 43, 84-85, 87-88 see also Snowstorms; Substorms; Thunder- storms Stratosphere electric field reductions in, 179-180 mass spectrometric analysis of, 186 morphology of aerosols in, 168 sulfuric acid content of, 175, 180, 187 temperature characteristics of, 183 see also Lower stratosphere, 166 Substorms, 202, 226 Sulfuric acid in stratosphere, 175, 180, 187 Surge protectors, 35 T Telluric currents applications of measurements of, 247-249 biological effects of, 249 causes of, 232, 234-235 channeling of, 240-241 deep, 241-243 factors affecting flow of, 236-237 historical development of understanding of, 254-256 interactions with man-made systems, 1-2, 12, 243-247 monitoring earthquakes, volcanoes, and geodynamics with, 249 natural environment of, 12, 234-243 oceanic, 233 patterns, 234 planetary scale distribution, 233-234 role of in changing earth's astronomical motion, 248-249 shallow, 241 study difficulties with, 250 use in remote-sensing of underground con- ductivity, 240 Thermal gradient, vertical, 55 Thermosphere electrical properties of, 189 temperature characteristics of, 183

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INDEX Thunder acoustic recordings of, 42 clap formation, 51 distance heard, 56 inside clouds, 54 measurements, 56-59 models of, 51 power spectrum of, 52, 56 produced by multiple-stroke lightning, 50 ranging technique, 57-58 ray tracing technique, 55-57 shock wave formation and expansion, 46- 52, 71 signature, 50-51, 57, 59 Thunderclouds charge location, 58-59 charge separation mechanisms in, 5, 132- 135, 207 charging rates in, 143-144 dipolar nature of, 5, 94-96 electrification of, 5, 90 electrostatically produced acoustic waves from, 58-59 models of, 132 nitrogen oxide levels in, 71 Thunderstorm Research International Pro- gram, 14, 90 Thunderstorms acoustic sources in, 46 as generators in global electric circuit, 6, 207-210, 224 cell activity reconstruction, 57, 84, 93, 104-107 charge distributions in, 208 charge motions and currents in, 102-104 charging mechanisms in, 114-130, 207 208 convection in, 109-110 current above, 212-213 development and severity, 43 dipolar structure of, 107, 208, 217-218 displacement current, 104 downdraft association with, 84-85, 87, 93 electric charge distribution in, 91-97, 100 102 electric field measurement in, 105 electric fields produced by, 92 electrical structure of, 90-113 evolution of, 27 flashing rates in, 27 forecasting of, 131 global activity of, 206-207, 210-212, 215, 219-220, 228 gust front in, 86-87 hail in, 84-86, 99, 121 in-cloud observations of, 98-99, 105 263 initial electrification of, 92, 97, 99 instruments for studying, 90 interconnection of lightning in, 36 latitudinal variation of, 81-82 lightning evolution in, 107-109 lightning modification of electrification in, 104-107 lightning-producing stage, 92 measurements, 93, 100, 109 mesocyclones in, 85 new technology for identification of, 88 origins, morphology, and dynamics, 81-89 particle velocity measurements in, 104 positive charge layer in, 109 precipitation role in, 93-94, 97-99, 101 103, 109, 131, 144 refractive effects in environment of, 54-55 research needs on, 110-111, 228 size of, 82-84 splitting of, 84 springtime, over U.S. Great Plains, 42 squall line, 42, 85-86 supercell, 42, 93 thermal structure during, 55-56, 95-97 tornadoes in, 84-85, 87-88 total effect of, 166 upper screening current in, 103 vertical circulation of air in, 82 vortex-type, 140 winter, 41-43, 45, 82, 96, 99, 126 Tides atmospheric, 200 use of telluric currents to study, 248 Titan, trace gases in atmosphere of, 75 Topological shielding, 67-68 Tornadoes death and damage from, 87 development and dynamics of, 87-88 global occurrence of, 87 Trans-Alaskan pipeline, 246 Troposphere aerosol density in, 171 conductivity in, 170-176 cosmic ray ionization rate in, 215 electrical structure of, 166-167 ion chemistry in, 8, 152 W ion mobility in, 170-176 small ion concentration in, 170-176 trace gases in, 152 see also Lower troposphere; Upper tropo sphere Turbulence analysis methodologies, 157 effect on electrode layer, 161 in planetary boundary layer, 8, 149-150, 153, 157, 163 X modeling, 160 structure of, 154 transport of electrical properties by, 154 U UHF radar, 106 United States lightning detection networks in, 28-29, 62 lightning strikes in, 30 springtime thunderstorms in, 42 zone of severe thunderstorms in, 82-83 Updrafts, role in thunderstorms, 4, 84-87, 92, 94, 100, 103-104, 127, 136, 142, 207 Upper atmosphere electric field and current interaction with, 203-204 electric field sources of, 195-205 electrical coupling between lower atmo- sphere and, 224-227 electrostatic potential of, 162 ionic reactions in, 152 studies needed on, 204 Upper troposphere, characteristics of aero- sols in, 168 V Venus lightning on, 39 trace gases in atmosphere of, 75 Vertical current density, 156 Vertical sounding of electric fields, 94-95 Vertical wind shear, correlation with posi- tive CG lightning, 42 VHF radiation, lightning processes produc- ing, 36 Volcanic eruptions aerosols from, 168-170, 175, 181, 187 E1 Chichon, 9, 169-170, 175 electrification associated with, 215-216 Workman-Reynolds effect, 138-139 X rays Bremsstrahlung, 185, 213 solar, 184, 213-212