This book provides a new look at the climatic history of the last 2.6 million years during the ice age, a time of extreme climatic fluctuations that have not yet ended. This period also coincides with important phases of human development from Neanderthals to modern humans, both of whom existed side by side during the last cold stage of the ice age. The ice age has seen dramatic expansions of glaciers and ice sheets, although this has been interspersed with relatively short warmer intervals like the one we live in today. The book focuses on the changing state of these glaciers and the effects of associated climate changes on a wide variety of environments (including mountains, rivers, deserts, oceans and seas) and also plants and animals. For example, at times the Sahara was green and colonized by humans, and Lake Chad covered 350,000 km2 – larger than the United Kingdom. What happened during the ice age can only be reconstructed from the traces that are left in the ground. The work of the geoscientist is similar to that of a detective who has to reconstruct the sequence of events from circumstantial evidence. The book draws on the specialisms and experience of the authors who are experts on the glacial history of the Earth.
Readership: Undergraduate and postgraduate students studying the Quaternary, researchers, and anyone interested in climate change, environmental change and geology. The book provides a rich collection of illustrations and photographs to help the readers at all levels visualise the dramatic consequences of glacier expansions during the Ice Age.
About the Authors vii Preface ix Acknowledgements xi About the companion website xiii 1. Introduction 3 1.1 In the Beginning was the Great Flood 4 1.2 The Ice Ages of the Earth 14 1.3 Causes of an Ice Age 18 2. The Course of the Ice Age 27 2.1 When did the Quaternary Period Begin? 27 2.2 What’s in Stratigraphy? 33 2.3 Traces in the Deep Sea 35 2.4 Systematics of the Ice Age 43 2.5 Günz, Mindel, Riss and Würm: Do They Still Apply? 46 2.6 Northern Germany and Adjacent Areas 58 2.7 The British Pleistocene Succession 76 2.8 Quaternary History of North America 86 2.9 The Course of the Ice Ages: A Global View 100 3. Ice and Water 107 3.1 The Origin of Glaciers 107 3.2 Recent Glaciers: Small and Large 113 3.3 Dynamics of Ice Sheets 121 3.4 Meltwater 129 4. Till and Moraines: The Traces of Glaciers 137 4.1 Till 137 4.2 Moraines 172 5. Meltwater: From Moulins to the Urstromtal 191 5.1 Fjords, Channels and Eskers 191 5.2 Outwash Plains and Gravel Terraces 202 5.3 Ice-dammed Lakes 207 5.4 Kames: Deposits at the Ice Margin 213 5.5 Urstromtäler 220 6. Maps: Where Are We? 227 6.1 Digital Maps 229 6.2 Satellite Images: Basic Data for Ice-Age Research 236 6.3 Projections and Ellipsoids 240 7. Extent of the Glaciers 243 7.1 Exploring the Arctic by Airship 243 7.2 Glaciers in the Barents Sea 244 7.3 Isostasy and Eustasy 246 7.4 Ice in Siberia? 252 7.5 Asia: The Mystery of Tibet 258 7.6 South America: Volcanoes and Glaciers 265 7.7 Mediterranean Glaciations 269 7.8 Were Africa, Australia and Oceania Glaciated? 272 7.9 Antarctica: Eternal Ice? 273 8. Ice in the Ground: The Periglacial Areas 277 8.1 Definition and Distribution 277 8.2 Extent of Frozen Ground during the Pleistocene 281 8.3 Frost Weathering 283 8.4 Cryoplanation 286 8.5 Rock Glaciers: Glaciers (Almost) Without Ice 288 8.6 Involutions 291 8.7 Solifluction 294 8.8 Periglacial Soil Stripes 296 8.9 Frost Cracks and Ice Wedges 297 8.10 Pingos, Palsas and other Frost Phenomena 301 9. Hippos in the Thames: The Warm Stages 311 9.1 Tar Pits of Evidence 311 9.2 Development of Fauna 312 9.3 Development of Vegetation 316 9.4 Weathering and Soil Formation 324 9.5 Water in the Desert: The Shifting of Climate Zones 336 9.6 Changes in the Rainforest 345 10. The Course of Deglaciation 349 10.1 Contribution to Landforms 349 10.2 Ice Decay 350 10.3 The Origin of Kettle Holes 354 10.4 Pressure Release 357 10.5 A Sudden Transition? 359 10.6 The Little Ice Age 363 11. Wind, Sand and Stones: Aeolian Processes 369 11.1 Dunes 369 11.2 Aeolian Sand 378 11.3 Loess 378 12. What Happened to the Rivers? 383 12.1 River Processes and Landforms 383 12.2 Dry Valleys 386 12.3 The Rhine: Influences of Alpine and Nordic Ice 387 12.4 The Elbe: Once Flowed to the Baltic Sea 396 12.5 The Thames: Influence of British Ice 400 13. North and Baltic Seas during the Ice Age 405 13.1 Development of the North Sea 406 13.2 Development of the Baltic Sea 414 14. Climate Models and Reconstructions 427 14.1 Ice Cores 427 14.2 The Marine Circulation 429 14.3 Modelling the Last Ice Sheets 431 14.4 Modelling Glaciers and Climate 442 15. Human Interference 447 15.1 Out of Africa: Humans Spread Out 448 15.2 Neanderthals and Homo sapiens 452 15.3 The Middle Stone Age 452 15.4 The Neolithic Period: The Beginning of Agriculture 453 15.5 Bronze and Iron 454 15.6 The Romans 455 15.7 Middle Ages 457 15.8 Recent Land Grab 457 15.9 Drying Lakes, Melting Glaciers and other Problems 459 15.10 The Anthropocene: Defining the Human Age? 465 References 469 Index 541
Jürgen Ehlers studied Geography at the University of Hamburg. In 1978 he did his PhD with a study in glacial geomorphology. Since then Ehlers worked at the Geological Survey of Hamburg, where he was in charge of the geological mapping until his retirement in 2013. He organised the INQUA project Extent and Chronology of Quaternary Glaciations with both Phil Gibbard and Phil Hughes and this global compilation was published in 2011. Philip Hughes is Reader in Physical Geography at The University of Manchester, UK. He studied for his first degree reading geography at the University of Exeter graduating in 1999. This was followed by a Masters in Quaternary Science, then a PhD in Geography, both at the University of Cambridge (Darwin College). He is Subject Editor in Geomorphology and Quaternary Geology for the Journal of the Geological Society. Philip Gibbard is Professor of Quaternary Palaeoenvironments at the University of Cambridge, UK, and a Dosent in the University of Helsinki, Finland. He is past-chair of the International Commission on Stratigraphy's Quaternary Subcommission. He is currently President, and was formally Secretary and member, of the Stratigraphy and Geochronology Commission of INQUA, and is a member of the INQUA Subcommission of European Quaternary Stratigraphy and the Geological Society of London's Stratigraphy Commission. His research is focused on Quaternary and late Tertiary terrestrial and shallow marine sedimentation, stratigraphy and palaeoenvironmental evolution throughout Europe, but he has also worked in the Arctic, North America, India and South-East Asia.
