Hurricanes: Their Nature and Impacts on Society - Climate Science ...

More documents

Recommendations

Info

80 HURRICANES: THEIR NATURE AND IMPACT ON SOCIETY 9201 :E .§: f 940 ~ .. .. .. a: E 960 c: .. u 980 45 (miles per hour) 90 135 1000 I I I , I 20 30 40 50 60 70 Wind Speed (meters per second) Figure 3.11 The average relation between wind speed <strong>and</strong> central pressure in an Atlantic hurricane. Source: Simpson <strong>and</strong> Riehl (1981). Reproduced by permission of the Louisiana State Press Effects of Vertical Wind Shear on Tropical Cyclones ,.~. '-"-"-"-" -"-"-A.-A-'-~-~-~~~-'--,,--,,-, WEAK SHEAR = FAVORABLE c-:::.~ . "" upper level winds 1\ +- LJ, lower level winds ~~-~ ~~~- -~ ,-, STRONG SHEAR= UNFAVORABLE low clouds high clouds Figure 3.12 A schematic illustrating the effect of vertical shear of the horizontal wind on tropical cyclone development. Figure provided by Stanley Goldenberg <strong>and</strong> Neal Dorst of the Hurricane Research Division AOMUNOAA
TROPICAL CYCLONES ON PLANET EARTH of the storm. A disruption in the outflow from the hurricane, due to the upperlevel divergence being replaced by upper-level convergence, as might occur due to large-scale atmospheric circulation changes, can also weaken <strong>and</strong> even dissipate a storm. <strong>Hurricanes</strong> also weaken rapidly when they traverse over cool water or inl<strong>and</strong> after they make l<strong>and</strong>fall (Kaplan <strong>and</strong> DeMaria 1995). There are two major reasons for the decay of hurricanes over a cool ocean or after l<strong>and</strong>fall. First, a hurricane requires that the warmest temperatures which are associated with the storm be in its center in order for the heat engine to work. However, as air spirals into a hurricane, it exp<strong>and</strong>s as a result of the lower pressures closer to the eye. Unless heat is added, this expansion results in cooling. (The same process occurs when air is let out of a tire. The exp<strong>and</strong>ing air at the nozzle from the pressurized tire is substantially colder than the surrounding air.) The cooling works against maintaining the heat engine.. This cooler air is not a favorable environment for continued thunderstorm development. Over l<strong>and</strong> <strong>and</strong> cool ocean surface waters, there is no heat source to counteract this cooling. The direct result is that thunderstorms weaken within the eye wall. The low central pressure of the tropical cyclone correspondingly rises as the coupling between the lower <strong>and</strong> upper troposphere is reduced <strong>and</strong>, as a result, the divergent winds in the upper levels of the tropical cyclone are diminished in strength. Thus, the eye wall tends to be destroyed as the hurricane weakens to tropical storm strength. The second reason that hurricanes decay over l<strong>and</strong> <strong>and</strong> cold oceans is that they lose the unlimited source of water vapor from the warm ocean water which is essential for maintaining the strong thunderstorms in the eye wall region... Wind speeds also decrease near the ground after l<strong>and</strong>fall. While not directly related to a hurricane's decay, this decrease in wind speed near the ground is due to the aerodynamic roughness of the l<strong>and</strong>. Trees, buildings, <strong>and</strong> even grassl<strong>and</strong>s tend to be rough surfaces compared to the ocean, with the result that wind is decelerated. One major result of this difference in roughness is that, even if the wind well above the surface remained constant at l<strong>and</strong>fall, the greater retardation of the flow by the rougher surface over l<strong>and</strong> would result in slower wind speeds at the surface. The cooler air over l<strong>and</strong> magnifies this reduction in wind speed near the surface even further. Therefore, while the winds well above the ground may even accelerate, as those levels tend to become decoupled from frictional retardation by the surface, the winds near the surface can become quite weak. While this decoupling of near surface flow from the winds aloft does not .For example, air which originates at a pressure of 1000 mb <strong>and</strong> 80°F (27°C) in the region surrounding the storm would cool to 64°F (18°C) at a pressure near the center of a storm of 900 mb, unless heat were added. ..A surface of water evaporates at a rate which is directly related to its surface temperature. For the same amount of moisture just above the surface, <strong>and</strong> a surface pressure of 1000 mb, an ocean area with a temperature of 80°F (27°C), for example, will evaporate at a rate about 64% greater than when the surface is at 64°F (18°C). 81
Page 2 and 3:
Hurricanes
Page 4 and 5:
Copyright @ 1997 by John Wiley & So
Page 6 and 7:
Dedication Foreword. Preface. Conte
Page 8 and 9:
CONTENTS 5.3 5.2.3 WindY. . 5.2.4 R
Page 10 and 11:
Foreword Before the mid-l 960s, stu
Page 12 and 13:
X11 FOREWORD The lessons of Camille
Page 14 and 15:
XVI PREFACE One of the fundamental
Page 16 and 17:
XVlll PREFACE about the need for so
Page 18 and 19:
2 HURRICANES: THEIR NATURE AND IMPA
Page 20:
4 HURRICANES: THEIR NATURE AND IMPA
Page 23 and 24:
INTRODUCfION: SCffiNCE, POLICY, AND
Page 25 and 26:
INTRODUcnON: SCIENCE, POLICY, AND H
Page 27 and 28:
INTRODUCTION: SCIENCE, POLICY, AND
Page 29 and 30:
INTRODUcrION: SCIENCE, POLICY, AND
Page 31 and 32:
INTRODUcrION: SCIENCE, POLICY, AND
Page 33 and 34:
I I I I A -Nr"1v ~ r/) ,:,.," 0- 0-
Page 35 and 36:
INTRODUCfION: SCIENCE, POLICY, AND
Page 37 and 38:
21 INTRODUCTION: SCIENCE, POLICY, A
Page 39 and 40:
INTRODUCfION: SCffiNCE, POLICY, AND
Page 41 and 42:
Page 43 and 44:
Page 45 and 46: INTRODUCfION: SCIENCE, POLICY, AND
Page 47 and 48: CHAPTER 2 The US Hurricane Problem
Page 49 and 50: THE US HURRICANE PROBLEM human acti
Page 51 and 52: THE US HURRICANE PROBLEM of their p
Page 53 and 54: THE US HURRICANE PROBLEM 37 2.1.3 S
Page 55 and 56: THE US HURRICANE PROBLEM 39 activit
Page 57 and 58: THE US HURRICANE PROBLEM Figure 2.3
Page 59 and 60: THE US HURRICANE PROBLEM on an intr
Page 61 and 62: THE US HURRICANE PROBLEM Table 2.1
Page 63 and 64: TIm us HURRICANE PROBLEM ~ I (a) -.
Page 65 and 66: THE US HURRICANE PROBLEM emissions)
Page 67 and 68: THE US HURRICANE PROBLEM 51 Figure
Page 69 and 70: THE US HURRICANE PROBLEM (ODDs) 193
Page 71 and 72: THE US HURRICANE PROBLEM 55 Figure
Page 73 and 74: THE US HURRICANE PROBLEM preparedne
Page 75 and 76: THE US HURRICANE PROBLEM 59 threat
Page 77 and 78: nIB US HURRICANE PROBLEM Table 2.3
Page 79 and 80: THE US HURRICANE PROBLEM 63 Paralle
Page 81 and 82: THE US HURRICANE PROBLEM Congress,
Page 83 and 84: THE US HURRICANE PROBLEM 67 Appendi
Page 85 and 86: TRC!>PICAL CYCLONES ON PLANET EARTH
Page 87 and 88: 71 TROPICAL CYCLONES ON PLANET EART
Page 89 and 90: TROPICAL CYCLONES ON PLANET EARTH F
Page 91 and 92: TROPICAL CYCLONES ON PLANET EARTH F
Page 93 and 94: TROPICAL CYCLONES ON PLANET EARTH (
Page 95: TROPICAL CYCLONES ON PLANET EARTH F
Page 99 and 100: TROPICAL CYCLONES ON PLANET EARTH N
Page 101 and 102: TROPICAL CYCLONES ON PLANET EARTH I
Page 103 and 104: TROPICAL CYCLONES ON PLANET EARTH 3
Page 105 and 106: 35 ,~ 20 1201 55 TROPICAL CYCLONES
Page 107 and 108: TROPICAL CYCLONES ON PLANET EARTH 9
Page 109 and 110: HURRICANE FORECASTS Figure 4.1 The
Page 111 and 112: * t " , " ' " i : , , j !' \ HURRIC
Page 113 and 114: HURRICANE FORECASTS (e) 7AM ~ ..i~~
Page 115 and 116: HURRICANE Fa RECASTS While the news
Page 117 and 118: ~-~ "'"00 ;-:'O-= -=-~"'" a",.- .->
Page 119 and 120: 102 HURRICANES: THEIR NATURE AND IM
Page 121 and 122: ~ 0, 2 ~ 2 ... ~ 0 ~ ~ 0 ':! Is I~
Page 127 and 128: ~ .I;~ a ;;'0 . ~ ! ~ " 0 'I' -§.
Page 135 and 136: CHAPTERS When a hurricane forms, it
Page 143 and 144: I ~..;. 126 HURRICANES: THEm NATURE
Page 145 and 146: ~'\ '" 128 \ '-- HURRICANES: THEIR
Page 147 and 148:
130 HURRICANES: THEIR NATURE AND IM
Page 149 and 150:
~ I 00- .". ~ -0( v 1a u .§ ~ ...g
Page 151 and 152:
Page 153 and 154:
Page 155 and 156:
Page 157 and 158:
Page 159 and 160:
Page 161 and 162:
Page 163 and 164:
Page 165 and 166:
Page 167 and 168:
Page 169 and 170:
Page 171 and 172:
Page 173 and 174:
CHAPTER? 7.1 INTRODUCflON As recoun
Page 175 and 176:
Page 177 and 178:
Page 179 and 180:
Page 181 and 182:
Page 183 and 184:
Page 185 and 186:
Page 187 and 188:
Page 189 and 190:
Page 191 and 192:
Page 193 and 194:
Page 195 and 196:
Page 197 and 198:
Page 199 and 200:
Page 201 and 202:
Page 203 and 204:
Page 205 and 206:
Page 207 and 208:
Page 209 and 210:
Page 211 and 212:
APPENDIX A CHAPTER! Byerly, R., 199
Page 213 and 214:
Page 215 and 216:
40 000 30 000 20'000 10 000 APPENDI
Page 217 and 218:
Page 219 and 220:
Page 221 and 222:
APPENDIX C Selected Data on Tropica
Page 223 and 224:
Page 225 and 226:
Figure C.4 Cont: Tracks of intense
Page 227 and 228:
'-'2 ..~ ,-..~ \OQ. ~~ -I" -(') 3.
Page 229 and 230:
APPENDIX C 209 '";ij' 40 Q) ~ C) Q)
Page 231 and 232:
211 APPENDIX D Table D.2 Eastern No
Page 233 and 234:
APPENDIX D Table D.6 Western Austra
Page 235 and 236:
APPENDIX D Table D.8 Fiji Region Na
Page 237 and 238:
APPENDIX D Table 0.10 Southeast Ind
Page 239 and 240:
: 8. ~A ". ~ 00 tU : V ~ ~ ~ V z 8,
Page 241 and 242:
Page 243 and 244:
on "'-va , £.c 0 I::.cp. V'O cn ,'
Page 246 and 247:
. OK OK U ~ ,. , , ..' ..~ '"' Z !
Page 248 and 249:
UJ ~ UJ P-'-'" s~~ 0 In + In O-o>,V
Page 250 and 251:
~ =.d.- ~ 0 ..., E-' g S u 'U~ =.g'
Page 252 and 253:
.s~~ ~...:s ~.9: .- .. ..c ..co " ,
Page 254 and 255:
APPENDIX E 233
Page 256 and 257:
APPENDIX E In sum, TDS provides an
Page 258 and 259:
APPENDIX 0 ~ION E 237 A period of t
Page 260 and 261:
APPENDIX E IF SITUATION W~S P (alp)
Page 262 and 263:
29. APPENDIX E p (0) 5 (a/p) T (alp
Page 264 and 265:
APPENDIX E p (0) p p S T (a/o) (a/p
Page 266 and 267:
APPENDIX E p p 5 p (alp) (r) S (r)
Page 268 and 269:
APPENDIX E 247 P (al p p P (alp) p
Page 270 and 271:
D APPENDIX E s s s s s s S T T T T
Page 272 and 273:
APPENDIX E 251 IMMEDIATE EMERGENCY
Page 274 and 275:
APPENDIX E 253 p p T (alp) (a/o) (0
Page 276 and 277:
APPENDIX E P (a/s) P falsI 5 (alp)
Page 278 and 279:
~ APPENDIX F 257 lOP = 5/9°C 1°C
Page 280 and 281:
REFERENCES 259 Nemec, J.M. Nigg <st
Page 282 and 283:
REFERENCES 261 Cochran, L.
Page 284 and 285:
REFERENCES 263 Etzioni, A., 1985: M
Page 286 and 287:
REFERENCES 265 Graham, B., 1992: An
Page 288 and 289:
REFERENCES 267 Katz, R.W., 1993: To
Page 290 and 291:
REFERENCES 269 Mesthene, E.G., 1967
Page 292 and 293:
REFERENCES 271 south Florida. Part
Page 294 and 295:
REFERENCES 273 Smith, K., 1992: Env
Page 296 and 297:
REFERENCES 275 Wolensky, R.P. <stro
Page 298 and 299:
INDEX 277 eye wall concentric eye w
Page 300:
INDEX silver iodide 112 Simpson, Ro
show all

Hurricanes: Their Nature and Impacts on Society - Climate Science ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?