Preface ................................................... xiii
1 Introduction ................................................. 1
1.1 Concept and rationale ................................... 1
1.2 Scope and classification of the hazards ................. 2
1.3 Hazard awareness ........................................ 5
1.4 Physical properties of ice .............................. 7
1.5 Hazard and risk ......................................... 8
1.6 Summary ................................................ 10
2 Arctic Sea Ice .............................................. 13
2.1 Introduction ........................................... 13
2.2 The Arctic Ocean ....................................... 15
2.3 Sea ice ................................................ 17
2.3.1 Definition and formation ........................ 17
2.3.2 Thickness and age ............................... 17
2.3.3 Distribution and extent ......................... 21
2.4 Impacts ................................................ 23
2.5 Direct impacts ......................................... 24
2.5.1 Entrapment ...................................... 24
2.5.2 Access to Arctic sea ice ........................ 24
2.5.3 Shore ice override (ivu) ........................ 27
2.6 Indirect impacts ....................................... 29
2.6.1 Coastal erosion ................................. 29
2.6.2 Access to the Arctic Ocean space following ice
loss ............................................ 34
2.6.3 Iceberg severity ................................ 35
2.6.4 Ice sheet stability ............................. 35
2.6.5 Ecosystems ...................................... 35
2.6.6 Climate change and the MOC ...................... 37
2.7 Mitigation ............................................. 38
2.7.1 Introduction .................................... 38
2.7.2 Sea-ice presence ................................ 39
2.7.3 Sea-ice loss .................................... 41
2.8 Summary ................................................ 42
3 Ice Sheets - Antarctica and Greenland ....................... 45
3.1 Introduction ........................................... 45
3.2 Ice sheet systems ...................................... 47
3.2.1 Ice domes ....................................... 48
3.2.2 Ice streams and outlet glaciers ................. 49
3.2.3 Ice shelves ..................................... 49
3.2.4 Sea ice ......................................... 51
3.3 Greenland .............................................. 52
3.4 Antarctica ............................................. 56
3.5 Impacts of ice sheet loss .............................. 62
3.5.1 Sea-level rise .................................. 62
3.5.2 Iceberg flux .................................... 65
3.5.3 Ecosystem change ................................ 66
3.5.4 Climate and ocean circulation change ............ 67
3.6 Mitigation ............................................. 68
3.7 Summary ................................................ 69
4 Icebergs .................................................... 71
4.1 Introduction ........................................... 71
4.2 Iceberg characteristics ................................ 72
4.2.1 Composition ..................................... 72
4.2.2 Size ............................................ 73
4.2.3 Shape ........................................... 74
4.2.4 Sources ......................................... 75
4.2.5 Distribution .................................... 76
4.2.6 Life expectancy ................................. 79
4.3 Iceberg impact and risk ................................ 81
4.3.1 Ship-iceberg collisions ......................... 82
4.3.2 Iceberg-fixed installation collisions ........... 86
4.3.3 Sea bed scouring ................................ 88
4.3.4 Impact on ecological systems .................... 88
4.3.5 Impacts on global climate ....................... 89
4.4 Iceberg mitigation ..................................... 90
4.4.1 Detection, monitoring, databases and research ... 91
4.4.2 Threat evaluation and prediction ................ 95
4.4.3 Ice management .................................. 96
4.4.4 Avoidance ....................................... 97
4.5 Summary ................................................ 98
5 Glaciers ................................................... 101
5.1 Introduction .......................................... 101
5.2 Inherent glacier hazards .............................. 102
5.2.1 Crevasses ...................................... 102
5.2.2 Seracs ......................................... 104
5.2.3 Ice avalanches ................................ 104
5.2.4 Complex avalanches ............................ 113
5.2.5 Ponded lakes .................................. 116
5.3 Glacier mass balance changes ....................... 116
5.3.1 Advancing glaciers ............................ 117
5.3.2 Surging glaciers .............................. 118
5.3.3 Retreating glaciers ........................... 121
5.4 Mitigation measures .................................. 129
5.5 Summary
6 Glacier Lake Outburst Floods (GLOFs) ....................... 133
6.1 Introduction .......................................... 133
6.2 The glacial meltwater system ....................... 134
6.3 GLOFs ................................................. 134
6.4 Trigger mechanisms ................................... 136
6.5 Risk .................................................. 142
6.6 Mitigation ............................................ 150
6.6.1 Hard measures (engineering) ................... 150
6.6.2 Soft measures ................................. 151
6.7 Summary ............................................... 154
7 Permafrost ................................................. 157
7.1 Introduction .......................................... 157
7.2 Permafrost distribution and characteristics ........... 159
7.3 Permafrost hazardousness .............................. 163
7.4 Lowland permafrost hazards ............................ 167
7.4.1 Mitigation measures ............................ 173
7.4.2 Climate change ................................. 174
7.4.3 Mapping ........................................ 175
7.4.4 Geotechnical engineering ....................... 178
7.5 Mountain permafrost hazards ........................... 189
7.5.1 Mitigation strategies .......................... 195
7.6 Summary ............................................... 201
8 Snow Avalanches ............................................ 203
8.1 Introduction .......................................... 203
8.2 Definition, classification and motion ................. 204
8.3 Factors promoting avalanches .......................... 207
8.3.1 Meteorology .................................... 207
8.3.2 Terrain ........................................ 211
8.4 Impacts of avalanches ................................. 212
8.4.1 Damage ......................................... 214
8.4.2 Fatalities ..................................... 214
8.5 Mitigation methods .................................... 218
8.5.1 Information .................................... 219
8.5.2 Modification and control ....................... 225
8.5.3 Avoidance ...................................... 227
8.6 Summary ............................................... 236
9 River Ice - Ice Jams and Ice Roads ......................... 237
9.1 Introduction .......................................... 237
9.2 Ice jams .............................................. 238
9.2.1 Introduction ................................... 238
9.2.2 Ice formation and freeze-up .................... 241
9.2.3 Ice breakup .................................... 246
9.2.4 Ice jam processes and sites .................... 248
9.2.5 Ice jam impacts ................................ 250
9.2.6 Ice jam mitigation ............................. 253
9.3 Ice roads ............................................. 259
9.3.1 Introduction ................................... 259
9.3.2 Ice-forming processes and ice types ............ 260
9.3.3 Construction ................................... 262
9.3.4 Loading ........................................ 263
9.3.5 Road use ....................................... 265
9.3.6 Hazards ........................................ 267
9.4 Summary ............................................... 272
10 Winter Storms - Ice Storms and Blizzards ................... 273
10.1 Introduction .......................................... 273
10.2 Definitions ........................................... 274
10.3 Weather systems and processes ......................... 276
10.3.1 Air pressure patterns .......................... 276
10.3.2 Air temperature ................................ 280
10.4 Impacts ............................................... 282
10.4.1 Fatalities and injuries ........................ 285
10.4.2 Physical damages ............................... 286
10.4.3 Economic losses ................................ 286
10.4.4 Transport and traffic disruption ............... 287
10.4.5 Power loss ..................................... 289
10.5 Mitigation ............................................ 289
10.5.1 Forecasting .................................... 290
10.5.2 Forward planning ............................... 291
10.5.3 Effective procedures ........................... 293
10.5.4 Public response ................................ 294
10.5.5 North-east Snowfall Impacts Scale (NESIS) ...... 295
10.5.6 Impact of climate warming ...................... 296
10.6 Summary ............................................... 298
11 Conclusions ................................................ 299
The Future References ...................................... 303
Glossary ................................................... 335
Acronyms ................................................... 341
Index ...................................................... 345
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