Preface to Fourth Edition xv

Preface to Third Edition xvii

Preface to Second Edition xix

Preface to First Edition xxi

Acknowledgments xxiii

Part I The Periglacial Domain 1

1 Introduction 3

1.1 The Periglacial Concept 3

1.2 Diagnostic Criteria 4

1.3 Periglacial Environments 5

1.4 The Periglacial Domain 6

1.5 The Periglacial Domain and the Cryosphere 9

1.6 Disciplinary Considerations 10

1.6.1 The Growth of Geocryology 10

1.6.2 The Challenge of Quaternary Science 11

1.6.3 Periglacial Geomorphology or Cold-Region Geomorphology? 12

1.7 Societal Considerations 12

1.8 The Growth of Periglacial Knowledge 13

2 Periglacial Climates 17

2.1 Boundary Conditions 17

2.2 Cold Deserts 17

2.3 Regional Climates 19

2.3.1 High Arctic Climates 22

2.3.2 Continental Climates 24

2.3.3 Alpine Climates 24

2.3.4 Montane Climates 25

2.3.5 Climates of Low Annual Temperature Range 25

2.3.6 Antarctica: A Special Case 26

2.4 Snow and Ice 26

2.5 Wind 28

2.6 Ground Climates 28

2.6.1 The 'n'-Factor 28

2.6.2 TheThermal Offset 29

2.6.3 The Ground Temperature Regime 31

2.7 Periglacial Climates and Global Climate Change 35

2.7.1 Basic Facts 37

2.7.2 Why Climate-Cryosphere Interactions Accelerate ClimateWarming 38

3 Periglacial Ecosystems 41

3.1 General Statement 41

3.2 Biogeographic Zonation and Major Vegetation Types 41

3.3 Adaptations to Cold, Snow,Wind and Aridity 44

3.4 The Effect of Vegetation 44

3.5 The Polar Deserts 47

3.5.1 High Polar Deserts 47

3.5.2 The Polar Semi-Deserts 47

3.6 The Polar Desert-Tundra Transition 49

3.7 The Low-Arctic Tundra 49

3.8 The Forest-Tundra Bioclimatic Boundary (The Tree Line) 53

3.9 The Boreal Forest 56

3.10 The Alpine and Montane Ecosystems 58

3.11 Antarctica - A Special Case 60

3.12 Periglacial Ecosystems and Climate Change 61

Part II Frozen Ground and Permafrost 63

4 Ground Freezing, Permafrost and the Active Layer 65

4.1 Introduction 65

4.2 Ground Freezing 65

4.2.1 Basic Concepts 65

4.2.2 Ice Segregation 67

4.2.3 'The Frozen Fringe' 69

4.2.4 Frost Heave 69

4.3 Perennially-Frozen Ground (Permafrost) 70

4.4 Moisture and IceWithin Permafrost 72

4.5 Thermal and Physical Properties 73

4.5.1 The Geothermal Regime 73

4.5.2 The TTOP Model 76

4.5.3 Physical Properties 77

4.5.4 Thermal Properties 78

4.6 Permafrost Hydrology 78

4.6.1 Aquifers 79

4.6.2 Hydrochemistry 80

4.6.3 Groundwater Icings 81

4.7 The Active Layer 82

4.7.1 Terminology 82

4.7.2 The Active-LayerThermal Regime 83

4.7.3 The Transient Layer 83

4.7.4 The Stefan Equation 84

5 Permafrost Distribution and Stability 87

5.1 Introduction 87

5.2 Controls over Permafrost Distribution 87

5.2.1 Relief and Aspect 87

5.2.2 Rock Type 88

5.2.3 Vegetation 90

5.2.4 Snow Cover 90

5.2.5 Fire 92

5.2.6 Lakes and SurfaceWater Bodies 92

5.3 Spatial Extent of Permafrost and Frozen Ground 93

5.3.1 Latitudinal Permafrost 93

5.3.2 Alpine (Mountain) Permafrost 95

5.3.3 Montane Permafrost 98

5.3.4 Seasonally-Frozen Ground 100

5.4 Sub-Sea and Relict Permafrost 101

5.4.1 Sub-Sea Permafrost 101

5.4.2 Relict (Terrestrial) Permafrost 101

5.5 Permafrost and Ecosystems 102

5.6 Permafrost Monitoring and Mapping 104

5.6.1 CALM and GTN-P (TSP) 104

5.6.2 BTS and Mountain Permafrost Probability Mapping 106

5.7 ClimateWarming and Permafrost 106

5.7.1 Evidence forWarming Permafrost 107

5.7.2 Evidence for Thawing Permafrost 109

6 Ground Ice and Cryostratigraphy 111

6.1 Introduction 111

6.2 Quantitative Parameters 111

6.3 Epigenetic, Syngenetic and Polygenetic Permafrost 112

6.4 Classification 113

6.4.1 The Russian Approach 113

6.4.2 The North American Approach 114

6.5 Main Ground Ice Types 115

6.5.1 Pore Ice 115

6.5.2 Segregated Ice 116

6.5.3 Intrusive Ice 117

6.5.4 Vein Ice 118

6.5.5 Other Types of Ice 118

6.6 Ice Distribution 118

6.6.1 Amounts 118

6.6.2 Distribution with Depth 120

6.6.3 Ice in Bedrock 120

6.6.4 Ice in Poorly-Lithified Sediments 121

6.7 Cryostratigraphy and Cryolithology 124

6.7.1 Cryostructural Analysis 125

6.7.2 Cryostructures of Epigenetic and Syngenetic Permafrost 128

6.7.3 Thaw Unconformities 129

6.7.4 Aggradational Ice 131

6.7.5 Icy Bodies and Ice, Sand and Soil Pseudomorphs 131

6.8 Ice Crystallography 132

6.9 Ice Geochemistry 133

6.10 Massive Ice and Massive-Icy Bodies 133

6.10.1 Nature and Extent 134

6.10.2 Intra-Sedimental Ice 135

6.10.3 Buried Glacier Ice 136

6.11 Cryostratigraphy and Past Environments 136

7 Aggradational Permafrost Landforms 139

7.1 Introduction 139

7.2 How Does Permafrost Aggrade? 139

7.2.1 The Illisarvik Drained-Lake Experiment 139

7.3 Thermal-Contraction-Crack Polygons 141

7.3.1 Coefficients ofThermal Expansion and Contraction 141

7.3.2 Ice, Sand and Soil ('Ground')Wedges 144

7.3.3 Development of the Polygon Net 144

7.3.4 Polygon Morphology 145

7.3.5 Controls over Cracking 147

7.3.6 Climatic Significance 150

7.4 Ice and SandWedges 151

7.4.1 EpigeneticWedges 154

7.4.2 SyngeneticWedges 154

7.4.3 Anti-SyngeneticWedges 156

7.4.4 Growth and Deformation ofWedges 156

7.5 Organic Terrain 156

7.5.1 Palsas 157

7.5.2 Peat Plateaus 158

7.6 Frost Mounds 158

7.6.1 Perennial-FrostMounds 158

7.6.2 Hydraulic (Open) System Pingos 159

7.6.3 Hydrostatic (Closed) System Pingos 161

7.6.4 Other Perennial-FrostMounds 165

7.6.5 Seasonal-Frost Mounds 165

7.6.6 Hydrolaccoliths and Other Frost-Induced Mounds 165

8 Thermokarst Processes and Landforms 169

8.1 Introduction 169

8.2 Thawing Ground 169

8.2.1 Thaw Strain andThaw Settlement 169

8.2.2 Potential Depths of Soil Freezing andThawing 170

8.2.3 The Development of Thermokarst 170

8.3 Causes ofThermokarst 171

8.3.1 General Comments 172

8.3.2 Specific Causes 174

8.4 Thaw-Related Processes 176

8.4.1 Thermokarst Subsidence (Thaw Settlement) 176

8.4.2 Thermal Erosion 176

8.4.3 Other Processes 176

8.5 Thermokarst Sediments and Structures 177

8.5.1 Involuted Sediments 177

8.5.2 Retrogressive-Thaw-Slumps and Debris-Flow Deposits 178

8.5.3 Ice-Wedge Pseudomorphs and Composite-Wedge Casts 179

8.5.4 Ice, Silt, Sand and Gravel Pseudomorphs 180

8.6 Thermokarst Landscapes 181

8.6.1 The Alas-Thermokarst Relief of Central Yakutia 182

8.6.2 TheWestern North American Arctic 185

8.6.3 The Ice-Fee Areas of Continental Antarctica 185

8.7 Ice-Wedge Thermokarst Relief 186

8.7.1 Low-Centred Polygons 186

8.7.2 High-Centred Polygons 186

8.7.3 BadlandThermokarst Relief 186

8.8 Thaw Lakes and Depressions 187

8.8.1 Lakes and Táliks 189

8.8.2 Morphology 189

8.8.3 Growth and Drainage 189

8.8.4 OrientedThaw Lakes 191

Part III Periglacial Geomorphology 193

9 Cold-ClimateWeathering 195

9.1 Introduction 195

9.2 GeneralWeathering Facts 195

9.3 Freezing and Thawing Indices 196

9.4 Rock (Frost?) Shattering 197

9.4.1 Frost Action and Ice Segregation 197

9.4.2 Insolation and Thermal Shock 200

9.4.3 Perspective 202

9.5 ChemicalWeathering 204

9.5.1 Karkevagge 204

9.5.2 Solution and Karstification 205

9.5.3 SaltWeathering 208

9.6 CryogenicWeathering 208

9.6.1 Cryogenic Disintegration 210

9.6.2 The Coefficient of Cryogenic Contrast 210

9.6.3 Physico-Chemical Changes 212

9.6.4 Problematic Phenomena 212

9.7 CryobiologicalWeathering 213

9.8 Rates of Cold-Climate BedrockWeathering 214

9.9 Cryosols and Cryopedology 215

9.9.1 Cryosols 215

9.9.2 Classification 216

9.9.3 Cryosolic Micromorphology 216

10 Mass-Wasting Processes and Active-Layer Phenomena 219

10.1 Introduction 219

10.2 Slow Mass-Wasting Processes 219

10.2.1 Solifluction 219

10.2.2 Frost Creep 221

10.2.3 Gelifluction 223

10.2.4 Solifluction Deposits and Phenomena 223

10.3 Rapid Mass-Wasting Processes 226

10.3.1 Active-Layer-Detachment Slides 226

10.3.2 Debris Flows, Slush Flows and Avalanches 226

10.3.3 Rockfall 230

10.4 Snow Hydrology and Slopewash Processes 232

10.4.1 Snow Hydrology and Snowbanks 233

10.4.2 Surface and SubsurfaceWash 233

10.5 Active-Layer Phenomena 235

10.5.1 Frost Heaving 235

10.5.2 Bedrock Heave 235

10.5.3 Upward Heaving of Stones and Objects 235

10.5.4 Stone Tilting 237

10.5.5 Needle Ice 239

10.5.6 Frost Sorting 239

10.5.7 Cryoturbation 240

10.6 Patterned Ground 240

10.6.1 Sorted and Non-Sorted Circles 240

10.6.2 Mud Boils 243

10.6.3 Nets and Stripes 246

11 Azonal Processes and Landforms 247

11.1 Introduction 247

11.2 Fluvial Processes and Landforms 247

11.2.1 Major Rivers 248

11.2.2 Freeze-Up and Break-Up 251

11.2.3 Basin Hydrology 252

11.2.4 Sediment Flow, Surface Transport and Denudation 255

11.2.5...