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Gravity Currents: in the Environment and the Laboratory: Second Edition John E Simpson Index More Information Cambridge University Press 978-0-521-66401-1 - Gravity Currents: In the Environment and the Laboratory: Second Edition John E Simpson Index More information Index Aberfan, mud flow 1966,119 bath water, rotation in outflow, 227-8 acoustic fluidisation, 118 Bernoulli's equation, 143-4 acoustic sounding, 18, 64 Bhopal, 1984, dense gas disaster, 70 aegre, Trent bore, 96 billows at front, 142 aerosol Kelvin-Helmholtz, 147,149,225, 237 Lake Nyos, 136 numerical modelling, 238 sea-breeze front, Japan, 40 birds, at sea-breeze fronts, 40 air avalanche, katabatic gust front, 64 black smokers, 137 air cavities in ducts, 171 blocking, in stratified fluids, 187 air fluidisation, 118 complete, 192 aircraft hazards, 2,66-9,173 boom, to contain oil slicks, 108 front of gravity current, 66 bores microbursts, 67 axisymmetric, 196 take-off and landing, 66 energy loss, 7 warnings, 69 generation of, 24, 35,186 wind shear, 69 internal, 7, 99-101 ambient stratification, 186 Loch Ness, 99 two-layer system, 186 tidal, in rivers, 5, 97-9 uniform density gradient, 200 two-dimensional numerical model, 236 andhi (thunderstorm outflow), 14 undular, 5 anvil cloud, 12, 53 wavelength, 25 aphids, at sea-breeze fronts, 40 Boulder, Colorado, cold air drainage, 64 Araguari River, bore, 96 Boussinesq approximation, 181, 232 arc clouds, 46 box models, 71,169,172 Armero, mud flow, 134 Bradford football ground fire, 86 arrnyworm moth, 42 Brunt-Vaisala frequency, 198 arrested saline wedge, 145,154 bubbles, rising, for turbulence, 208 atmospheric bores, 21-3 buoyancy atmospheric gravity currents, 11-27 flux, 175 atrium, 83-5 frequency, 198 auto-suspension currents, 224 inertial regime, 214 avalanches, 112-22 viscous regime, 214 airborne snow, 2, 224 Burketown, N. Australia, 23 fluidisation, 114 bursting process in mudflows, 121 mud, 118-22 rock, 116-18 cables, submarine, cut by turbidity currents, 102, axisymmetrical collapse 103,224 experiments, 172-7 Cambrian colliery, 1965 explosion investigation, numerical model, 234 78 canyons, submarine, 102 barrier to gravity current catastrophic ignition in turbidity currents, 224 sloping above, 160 cavity flow, 143 porous, 158 Celtic Sea front, 91 solid, 159 circular ducts, lock exchange flow, 166 basal melting theory, fluidisation, 118 Cleveland, 1944 explosion, 69 basaltic lava, 127 CO2 saturation, Lake Nyos, 136 levees, 127 collision Surtsey, 127 gravity currents, 196 tunnel, 127 sea-breeze fronts, 23, 29-34 239 © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-66401-1 - Gravity Currents: In the Environment and the Laboratory: Second Edition John E Simpson Index More information 240 Index cold air drainage, 64 fires in buildings cold fronts, 49-52, Bradford football ground, 86 Connecticut River front, foam line, 92 King's Cross, 86 constant flux spread along ceiling, 85 parallel channel, 175 Fisher River, salt wedge, 92 radial flow, 177 fjords cooling-water requirements, 105 fronts in, 2, 94 Coriolis Loch Eil, 95 bathwater, 227-8 Loch Etiven 95 force, 59,227-30 waves in stratified layer, 200 Rossby number, 228 floating debris at front, 88-90,92 Seabreeze, 229 flow force, 143 southern hemisphere, 59 flow on rotating earth, 59, 227-31 Southerly Buster, 229 fluidisation, 221-4 Cousteau Society, 96 foam lines, 2, 92,101 Crete, Nebraska, 1969 gas explosion, 70 foremost point of gravity current, or nose, 140, crossing fronts, 197 152 curtain clouds, 34 Fraser River, Canada, 2 custard powder, suspension flow, 121 free surface flow, 165,178 frontogenesis, 32 fronts, anatomy of, 140-63 dam-break, 3 fronts, in the environment dam-break analogy, 4,167 fjords, 94 de Saussure, on debris flows, 118 estuaries, 91 debris and mud avalanches, 112,118-22 ocean, 88 decreasing depth, flow into, 160 sea-breeze, 2, 29-43, 211 demolished building, suspension current, thunderstorm outflows, 1,12-18, 233-4 218 fronts, formation and dissipation, 206, 210 dense gas, disasters Froude number, 143,147,149,191, 200 Bhopal, 1984, 70 Fujita, Professor T.T., 68 Montanasm, 1981, 70 Fundy, Bay of, 99 Cleveden,1944,69 Crete, Nebraska, 1969, 70 gas, spread of dense, 69-76 LosAlfraques, 1978, 70 Gibraltar Strait, flow over sill, 100 Meldrim, 1959, 70 glacier Mexico City, 1984, 70 erosion, 125 Potcherstroom, 1973, 70 galloping, 124 dense gas dispersion, 2,69-76 speeds. 123 models, 70-2 transportation of material, 125 field experiments, 72-6 winds, 63 densityjump, 177 gliders diffusion, turbulent, 208 curtain clouds, 34 diffusivity, eddy, 210 flights of 9 June 1968, 30 door, gravity current through, 2, 81 Lasham Gliding Centre, 31, 33, 35 doppler radar, 19 sea-breeze fronts, 29, 31 downwind fronts, 73 slope upwinds, 63 drainage of cold air, 64 swifts, flight with, 40 duck, plastic fluidised, 222 Golborne Colliery, 1979 accident, 79 dust Grand Banks, sediment slide, 102 airborne, 14 gravity waves, 9 cloud, 1 grid dynamic similarity, 11 oscillating, 206 turbulence, 206 Elm, rockfall, 1881,116 Gulf Stream, 88 energy loss, at bore, 7 gust front detection, 69 erosion of channel by turbidity currents, 219 H2 Sin Lake Nyos, 136 by turbulence, 207 haboob, sand and dust storm estuaries, fresh water gravity currents, 2 lobe and cleft structure, 14 © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-66401-1 - Gravity Currents: In the Environment and the Laboratory: Second Edition John E Simpson Index More information Index 241 raised nose, 140 Lake Superior, turbidity currents, 224 thunderstorm outflow, 14 lakes, plunge line, 95 Hangzhou, Qiantang bore, 96 landslides, submarine, 102 head, of gravity current, 140 laser 'radar', see lidar cut off in ambient stratification, 201 Lasham Gliding Centre, 31, 33, 35 form on slope, 179 lava, 127-8 head and tail winds, 153-4 layering number, in mines, 78 Health and Safety Executive lid, rigid sloping, 160 mine accidents, 78 lidar, 20 field experiments, 73-4 lobes and clefts, at front, 14,19, 34,62,142,147, heat sink, in numerical model, 233 149, 238 HEGADAS, dense gas model, 75 Loch Eil, renewal of deep water, 95 house, ventilation, 2, 81-2 Loch Etive, 95 hydraulic jump, 5,155,169,177,179 Loch Ness, internal bore, 99 hydrothermal vents lock exchange flows, 164 black smokers, 137 locusts mega-plumes, 138 at sea-breeze fronts, 42 hysteresis, in fluidisation experiments, 223 outlining front, 43 Los Alfraques, 1978 disaster, 70 Ice Ages, 125 low Reynolds number experiments, 213 ignition, of suspension current on slope, 224 immiscible fluids, laboratory experiments, 108 mamma cloud, at thunderstorm, 13 inclined thermal, 180 Maplin Sands, field experiment, 75 inertial regime, 214 Marco Polo, at Hangzhou, 98 insects, at sea-breeze fronts, 41 marker and cell, numerical model, 232 instabilities Mawson, Antarctica, katabatic winds, 64 billows, 142,147,149, 225, 237 mechanical fluidisation, 118 laboratory suspension flows, 121 Meldrim, gas explosion, 1959, 70 lobes and clefts, 14,19,34,62,142,147,149,238 Mexico City, gas explosion, 1978 and 1984, 70 viscous flow on slope, 215 microbursts, 67-8 internal bores Middlesbrough, smog, 38 atmosphere 7 mines generation by gravity current, 101,189-92 Cambrian Colliery, 78 lakes, 99 gases in, 76-80 ocean,8,99-100 Golborne Colliery, 79 internal solitary wave, 10 layering number, 78 internal waves, in continuous stratification, 200 mixing in gravity currents, 144, 207 intrusions, 194, 203 Moncton, New Brunswick, bore in Petitcodiac inversion, nocturnal, 21 River, 99 inviscid-flow theory, 142-4 Montanas, 1981 gas disaster, 70 Ionica building, 85 Morning Glory, 9, 21-3, 47 motor-gliders, 32 Jiang-jia Ravine, mud flows, 121 Mount Augustine, Alaska, 133 jokulhlaup, 134 Mount St Helens, 1980 eruption, 135-6 moving-floor experiments, 206 katabatic winds mud flows air avalanche, 64 bursting process, 121 fronts, 63-4 instabilities, 120 glacier winds, 64 Jiang-jia Ravine, China, 121 Mawson, Antarctica, 64 MtSt Helens, 135 Red Butte Canyon, 64 increase in frequency, 120 Kelvin-Helmholtz billows, 147,149, 223, 237 speed of, 119 King's Cross fire, 86 Stava disaster, 1985,120 Knight Inlet, flow over sill, 100 superelevation in canyon, 134 volcanic eruptions, 133 LNG, liquid natural gas, 69-70, 75 White Mountain, observations, 119 LPG, Liquid propane gas, 75 lahar, or mud flow, 119,133 Nevado del Ruis, Columbia, lahars from Lake Nyos, Cameroon, gas disaster, 136 eruption, 134 © in this web service Cambridge University Press www.cambridge.org Cambridge University Press 978-0-521-66401-1 - Gravity Currents: In the Environment and the Laboratory: Second Edition John E Simpson Index More information 242 Index New Brunswick, Canada, radar records, 42 radar Ngauruhoe, New Zealand, nuee ardente, 131 sea-breeze front, 41 Nice, France, 1979 unplanned turbidity current, thunderstorm outflows, 19-20 220 Red Butte Canyon, katabatic wind, 64 non-Newtonian flow, 221 reduced gravity, 4 nose, foremost point of gravity current, 140, release of fixed quantity of fluid, rectangular 152 channel, 166-72 nuees ardentes, 127,130 remote sensing numerical models lidar, 20,40 axisymmetrical outflow, 234 radar, 19, 41 dense gas spread, 70-2 Reynolds number HEGADASII, 75 definition, 11 gravity currents, 232 effect on profile, 140 high resolution, 235 effect on height of nose, 152 marker and cell, 232 flow under sloping lid, 161 thunderstorm outflow, 233 ratio of inertial to viscous forces, 214 undularbore, 236 limits of dependence, 11, 220 Richardson number, 77-8,147,154 obstacles, to gravity currents, 155 ring vortex, at microburst, 68
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