Geomorphology and Global Environmental Change

Cover......Page 1
Half-title......Page 3
Title......Page 5
Copyright......Page 6
Contents......Page 7
Contributors......Page 12
Preface......Page 15
Acknowledgements......Page 16
Acronyms and abbreviations......Page 17
1.1.1 Defining landscape and appropriate temporal and spatial scales for the analysis of landscape......Page 19
1.1.2 The global human footprint and landscape vulnerability......Page 20
1.1.5 The role of geomorphology......Page 21
1.2 Climatic geomorphology......Page 22
1.3.2 The scale linkage problem......Page 23
1.4.1 Landscape response to disturbance......Page 24
1.4.2 Azonal and zonal landscape change......Page 25
1.5 Landscape change......Page 26
1.5.2 The record from the ice caps and lake sediments......Page 27
1.6.1 Introduction......Page 28
Precipitation......Page 29
Trends in streamflow......Page 30
1.6.3 Projections for future changes......Page 31
1.7.1 Introduction......Page 32
1.7.2 Recent sea level rise......Page 33
1.7.3 Future sea level rise......Page 34
1.8.2 The sediment cascade......Page 35
1.8.4 The sediment budget......Page 36
1.9.1 Indirect factors......Page 37
Cultivated systems......Page 38
1.9.3 Conclusion......Page 39
1.10.1 Putting the ‘geo’ into the ‘bio’ debates......Page 40
1.10.2 Geomorphology, natural hazards and risks......Page 41
1.10.3 Geomorphology and unsustainable development......Page 42
1.11.1 Landscape change over long time periods......Page 43
1.11.3 Landscapes of transition......Page 44
1.11.4 Adaptive systems......Page 45
APPENDIX 1.1 The IPCC scenarios......Page 46
APPENDIX 1.2 Global Environmental Outlook scenarios to 2032 (GEO-3: see UNEP, 2002) and the fourth Global Environmental Outlook: environment for development (GEO-4)......Page 47
APPENDIX 1.4 The Land Use and Land Cover Change (LUCC )Project......Page 48
References......Page 49
2.1 Introduction......Page 55
2.1.2 Holocene climate change in mountains......Page 56
Ice cores......Page 57
Geoecological zonation......Page 58
2.1.4 Summary......Page 59
2.2.1 The sediment cascade in mountains......Page 60
The fine-grained sediment system......Page 61
2.3.3 Runoff and sediment transport......Page 62
2.4.1 A typology of mountain systems with respect to human influence......Page 63
2.4.2 Land use in mountain areas......Page 64
2.4.3 Summary......Page 66
2.5.4 Frozen ground......Page 67
Permafrost......Page 68
2.5.6 Glacier–runoff–sediment transport relations......Page 69
2.5.8 Summary of global implications of hydroclimate change in mountains......Page 70
The postglacial landscape of BC......Page 71
Anticipated changes in the cryosphere......Page 72
2.6.1 The distinction between land cover and land use......Page 73
Artificial snow-making......Page 74
Snow avalanches......Page 75
The industrial and service economy era: population development and landscape change since AD 1880......Page 76
Land cover changes......Page 77
Future scenarios: implications of climate warming on land cover in the Eastern Alps......Page 78
2.7.2 Uncertainties surrounding adaptive capacity in mountain landscapes......Page 79
2.7.3 Case study: the Ethiopian Highlands......Page 80
Environmental rehabilitation in the Tigray Highlands......Page 81
2.7.4 Summary......Page 82
References......Page 83
3.1.1 Objective of the chapter......Page 89
3.2.2 Lake types by climatic zone and area......Page 90
3.2.3 Summary......Page 91
3.3 The lake catchment as geomorphic system......Page 92
3.3.1 Catchment controls......Page 93
3.3.2 Relief, catchment area and regional climate......Page 94
3.3.3 Variability and lake catchment behaviour......Page 95
3.4.1 Physical mixing......Page 96
3.4.4 Sedimentation processes......Page 97
3.5 Hydroclimate changes and proxy data......Page 98
Particle size and stratigraphy as proxy for palaeo-precipitation......Page 115
3.5.2 Models and limitations for prediction......Page 117
A process-oriented model for lake catchment systems......Page 118
3.5.3 Hydroclimate changes interpreted from lake sediments......Page 119
3.6.1 Overuse of water for irrigation: Aral Sea and Lake Chad......Page 120
3.6.2 Accelerated erosion and sedimentation......Page 121
Lake Patzcuaro, Mexico......Page 123
Urbanisation, sewering and phosphate detergents......Page 124
3.6.6 Rainfall acidification......Page 125
3.7 Scenarios of future wetland and lake catchment change......Page 126
3.7.3 Vulnerability of terrestrial wetlands and lake catchments......Page 127
References......Page 128
4.2.1 The hillslope hydrological cycle......Page 132
The variable source area model: saturation-excess overland flow......Page 133
Agriculture and runoff......Page 134
Land drainage in peatlands......Page 135
Forest management and runoff......Page 136
4.3.1 The form of river channels......Page 137
Reinforcement of river banks......Page 140
Modifying the flow regime......Page 141
Diversions and canals......Page 142
4.4.2 The fluvial sediment cycle......Page 143
Forest land use......Page 146
Placer mining and gravel borrowing......Page 147
4.5.1 Introduction......Page 148
Colorado River......Page 149
The Indus basin projects......Page 151
The River Nile......Page 152
Huanghe (Yellow River), China......Page 154
4.6.1 Introduction......Page 155
4.6.2 Extent and scope of river restoration......Page 157
4.6.5 Perspective: relative scales of restoration and degradation......Page 158
4.7 Conclusions......Page 159
References......Page 160
5.1 Introduction......Page 164
5.2.1 Driving processes......Page 167
5.2.2 Twenty-first century changes......Page 168
5.2.3 Implications of geomorphic change......Page 169
5.3.1 Driving processes......Page 170
5.3.2 Twenty-first century changes......Page 172
5.3.3 Implications of geomorphic change......Page 175
Foredune system......Page 176
Dunefields......Page 180
Vegetation–dune interaction......Page 181
5.4.2 Twenty-first century changes in dune processes and landscapes......Page 182
5.5 Managing coastal geomorphic systems for the twenty-first century......Page 184
5.5.1 Danube Delta case study......Page 185
5.5.2 Conclusions......Page 186
References......Page 187
6.1 Introduction......Page 192
6.2 Coastal classification......Page 193
6.3.1 Introduction......Page 196
6.3.2 The role of sea level rise and sediment availability on large-scale, low-order coastal behaviour during the Holocene......Page 198
6.3.3 The applicability of the Bruun Rule......Page 199
6.3.4 The quantitative coastal tract......Page 200
6.4.1 Introduction......Page 201
6.4.2 The Holland coast primarily shaped by marine agencies (complex example of a secondary or mature coast)......Page 202
6.4.4 The Ebro Delta, a deltaic system with negligible marine supply and significant fluvial supply (example of a primary, youthful coast)......Page 203
6.4.5 UK cliffed coasts (example of a secondary or mature coast)......Page 204
6.4.6 Longshore redistribution and backbarrier exchanges or inlet influences......Page 206
6.5 Risk-based prediction and adaptation......Page 208
References......Page 210
7.1.1 Geomorphic units and morphodynamic framework for coral reef landforms......Page 214
7.2.1 Controls on coral reef carbonate production......Page 216
7.2.2 Cycling of calcium carbonate: influences upon coral reef framework and sediment deposition......Page 218
7.2.3 Implications of climatic and environmental change for carbonate budgets and geomorphology......Page 219
7.3 Coral reef landforms: reef and reef flat geomorphology......Page 222
7.3.1 Reef growth – sea level relations at geological timescales......Page 223
7.3.3 Coral reefs and increased sea surface temperatures......Page 226
7.3.5 Ocean temperatures, storminess and storm impacts on reefs......Page 227
7.3.6 Ocean acidification and coral reefs......Page 228
7.4 Reef sedimentary landforms......Page 229
Timing of sea level change, reef growth and landform accumulation......Page 231
Sediment supply......Page 232
7.4.2 Morphodynamics of reef sedimentary landforms......Page 233
7.4.3 Future trajectories of reef sedimentary landforms: resilience or instability......Page 234
7.5 Anthropogenic effects on sedimentary landforms......Page 236
7.6.1 Morphological trajectories for coral reefs and reef sedimentary landforms......Page 239
References......Page 242
8.1.1 Diversity and distribution of tropical rainforest climates......Page 248
8.1.3 Long-term history of the tropical rainforest biome and its distribution in relation to climate change......Page 249
8.2.1 Introduction......Page 251
8.2.2 Geomorphological processes in rainforest areas......Page 253
River flow......Page 254
Slope erosional processes......Page 255
Fluvial processes......Page 257
8.2.3 Landforms and landscape development including the influence of climate change......Page 258
Shifting agriculture and other traditional agricultural systems......Page 260
Logging......Page 262
8.3.1 Rainfall and temperature changes......Page 265
Rainstorm magnitude–frequency changes......Page 266
Tropical cyclone magnitude, track and frequency changes......Page 267
8.4 Approaches and methods for predicting geomorphological change: physical models versus conceptual/ empirical approaches......Page 268
8.5.1 IPCC predictions for tropical rainforest areas and their uncertainties......Page 269
8.5.2 Rainforest responses to climate change......Page 271
More frequent and intense dry periods and fire risks with a possibly more intense ENSO cycle......Page 272
Overall prospects for the tropical rainforest if high rates of deforestation continue......Page 273
Slope process changes......Page 274
Fluvial processes and landscape-scale changes......Page 275
Likely impacts in replacement land use areas......Page 276
8.7 Summary and conclusions......Page 277
References......Page 278
9.1.1 Distribution, nature and complexity......Page 282
Climate, geomorphology, soils and landscape evolution......Page 284
Fire, grazing and human activity......Page 285
9.1.3 Uncertainties......Page 287
9.2.1 Geomorphological inheritance......Page 289
9.2.2 Deep weathering, groundwater and inselbergs......Page 290
9.2.4 Duricrusts......Page 291
9.2.5 Dambos......Page 292
9.2.6 Pans......Page 293
9.2.7 Soil erosion by water......Page 294
9.3.1 Landscape sensitivity......Page 296
9.3.2 The Quaternary archive: some examples from the savannas of Africa and beyond......Page 298
9.4 A case study in geomorphic impacts of climate change: the Kalahari of southern Africa......Page 299
9.4.1 The Kalahari environment......Page 300
9.4.2 Landform sensitivity in the Kalahari: a Quaternary perspective......Page 301
9.4.3 The Kalahari in the future......Page 302
9.5 Concluding remarks......Page 303
References......Page 305
10.1 Introduction......Page 310
10.1.1 Causes of deserts......Page 311
10.2 Drivers of change and variability in desert geomorphic systems......Page 312
10.2.1 Natural drivers of change......Page 313
10.2.2 Human influences......Page 315
10.3.1 Desert rivers......Page 317
10.3.2 Terminal lake basins......Page 319
10.4 Aeolian systems......Page 320
10.4.1 Dust storms......Page 321
10.4.2 Dune systems......Page 322
10.5 Discussion......Page 325
References......Page 326
11.2 Geology, topography and soils......Page 331
11.3.1 Climate......Page 333
11.3.2 Hydrology and fluvial geomorphology......Page 334
11.3.3 Slope processes and soil erosion......Page 335
11.3.6 Vegetation characteristics and their geomorphic implications......Page 336
11.4 Long-term environmental change in Mediterranean landscapes......Page 337
11.4.3 Vegetation change......Page 339
11.4.5 Historical climatological and hydrological change......Page 340
11.5.1 Forests......Page 341
11.5.2 Pasture......Page 342
11.5.4 The agro-sylvo-pastoral system......Page 343
11.6 Contemporary and expected near-future land use changes......Page 344
11.7.1 Temperature and precipitation change......Page 346
11.7.2 Changes in water resources and flood hazard......Page 347
11.7.3 Sea level changes......Page 348
11.8.2 Implications of socioeconomic and land use changes......Page 349
11.8.3 Where to go......Page 350
References......Page 351
12.1.2 Background......Page 355
12.1.3 Some applied forest hydrology......Page 356
12.2.1 Spatial and topographic distribution of temperate forests and steppes......Page 357
12.4 Types, trajectories and vulnerabilities associated with anticipated mass wasting responses to climate change......Page 359
12.5.2 Example of forest conversion to pasture: New Zealand......Page 362
12.5.3 Example of forest harvesting effects: Pacific Northwest, North America......Page 364
12.5.4 Example of mountain roads: northern Yunnan, China......Page 366
12.6.1 Empirical approaches and models......Page 368
12.6.2 Physically based models......Page 369
12.6.3 Do existing technologies and models still apply in a changing environment?......Page 370
12.7 Summary and conclusions......Page 371
References......Page 372
13.1.1 The Arctic: a climate change ‘hotspot’......Page 378
13.1.2 Socioeconomic changes associated with globalisation......Page 380
13.1.4 International research framework and geomorphological services......Page 381
13.2.1 Permafrost indicators: observational data and predictive modelling......Page 382
13.2.4 Increased depth of thawing......Page 383
13.3 Permafrost thaw as a driving force of landscape change in tundra/taiga areas......Page 384
Quantification of thermokarst-affected terrain types in the Siberian coastal plains......Page 385
Palsas as geoindicators of climate changes in subarctic regions......Page 386
13.3.3 Interactions between permafrost degradation, morphodynamics, vegetation and snow cover......Page 387
13.4.1 Context and ongoing studies......Page 388
13.4.2 Geomorphological and geoecological services......Page 389
13.5 Socioeconomic impact and hazard implications of thermokarst activity......Page 390
13.5.2 Predictive hazard mapping......Page 391
Shishmaref: an Alaskan Inuit village at sea......Page 392
13.6.2 Accelerated coastal erosion in the Arctic: rates, processes, controls......Page 393
Evaluating the human impact on coastal stability in Varandei industrial complex, Pechora Sea......Page 394
13.8 Lessons from the past......Page 395
Salluit (Nunavik): how to cope with demographic growth in sensitive permafrost terrain......Page 396
References......Page 397
14.1 Introduction......Page 402
14.2 Distribution of ice sheets and ice caps......Page 403
14.3 Ice sheet and ice cap landscapes......Page 408
14.4 Ice sheets and ice caps: mass balance......Page 412
14.5 Ice flow and ice temperature......Page 414
14.6 External controls and feedbacks......Page 415
14.7 Landscapes of glacial erosion and deposition......Page 418
14.8.1 Antarctic Ice Sheet......Page 423
East Antarctic Ice Sheet......Page 424
West Antarctic Ice Sheet......Page 425
14.8.2 Greenland Ice Sheet......Page 427
Patagonian ice caps......Page 430
14.8.4 Wider implications......Page 431
References......Page 433
15.2.2 From global to regional, from AD 2100 to AD 2035 and AD 2300......Page 437
15.2.3 Placing geomorphology......Page 438
15.2.1 The two-dimensional, instantaneous modelled land surface......Page 439
15.2.2 Climate–land-cover–landform linkages......Page 440
15.3.1 Multiple drivers of landscape change......Page 441
15.3.2 The (relatively) unambiguous role of climate......Page 442
Scaling and the vexed question of near-future storminess......Page 443
Climate change, coasts and geomorphology......Page 444
15.3.4 Sea level......Page 445
15.3.5 Topographic relief......Page 446
15.3.6 Human activity......Page 447
Environmental hazards and storminess: the US Gulf and Atlantic coasts......Page 448
Environmental hazards and storminess: the UK east coast......Page 449
15.4 Conclusions: new geomorphological agendas for the twenty-first century......Page 450
15.4.1 Challenges to building geomorphological scenarios in response to global environmental change......Page 451
15.4.2 The intrinsic value of geomorphology and geodiversity......Page 452
15.4.3 Geomorphological services, sustainability and vulnerability......Page 453
References......Page 454
Index......Page 458