xvi
Precambrian History: The Formation of Earth’s
Continents 468
Earth’ s First Continents 469
The Making of North America 471
Supercontinents of the Precambrian 471
Geologic History of the Phanerozoic: The
Formation of Earth’s Modern Continents 473
Paleozoic History 474
Mesozoic History 474
Cenozoic History 475
Earth’s First Life 477
Paleozoic Era: Life Explodes 479
Early Paleozoic Life-Forms 480
Vertebrates Move to Land 481
The Great Permian Extinction 481
Mesozoic Era: Age of the Dinosaurs 483
Reptiles: The First True Terrestrial Vertebrates 484
Demise of the Dinosaurs 485
Cenozoic Era: Age of Mammals 487
From Reptiles to Mammals 487
Large Mammals and Extinction 488
THE CHAPTER IN REVIEW 491
KEY TERMS 491 GIVE IT SOME THOUGHT 491
COMPANION WEBSITE
20 Global Climate
Change 492
Climate and Geology Are Linked 494
The Climate System 494
How Is Climate Change Detected? 496
Seafloor Sediment—A Storehouse of Climate Data 496
Oxygen Isotope Analysis 497
Climate Change Recorded in Glacial Ice 497
Other Types of Proxy Data 498
Some Atmospheric Basics 499
Composition of the Atmosphere 499
Extent and Structure of the Atmosphere 501
Heating the Atmosphere 502
Energy from the Sun 502
The Fate of Incoming Solar Energy 503
The Greenhouse Effect 504
Natural Causes of Climate Change 505
Volcanic Activity and Climate Change 505
Solar Variability and Climate 508
Human Impact on Global Climate 509
Carbon Dioxide, Trace Gases,
and Climate Change 509
CO 2 Levels Are Rising 510
The Atmosphere’ s Response 511
The Role of Trace Gases 512
Climate-Feedback Mechanisms 514
Types of Feedback Mechanisms 514
Computer Models of Climate: Important Yet
Imperfect Tools 515
How Aerosols Influence Climate 515
Some Possible Consequences
of Global Warming 516
Sea-Level Rise 516
The Changing Arctic 518
Increasing Ocean Acidity 520
The Potential for “Surprises” 520
THE CHAPTER IN REVIEW 521
KEY TERMS 522 GIVE IT SOME THOUGHT 523
COMPANION WEBSITE 523
APPENDIX A
Metric and Engligh Units Compared 475
APPENDIX B
Topographic Maps 477
APPENDIX C
Landforms of the Conterminous
United States 481
GLOSSARY 483
INDEX 493
Precambrian History: The Formation of Earth’s
Continents 468
Earth’ s First Continents 469
The Making of North America 471
Supercontinents of the Precambrian 471
Geologic History of the Phanerozoic: The
Formation of Earth’s Modern Continents 473
Paleozoic History 474
Mesozoic History 474
Cenozoic History 475
Earth’s First Life 477
Paleozoic Era: Life Explodes 479
Early Paleozoic Life-Forms 480
Vertebrates Move to Land 481
The Great Permian Extinction 481
Mesozoic Era: Age of the Dinosaurs 483
Reptiles: The First True Terrestrial Vertebrates 484
Demise of the Dinosaurs 485
Cenozoic Era: Age of Mammals 487
From Reptiles to Mammals 487
Large Mammals and Extinction 488
THE CHAPTER IN REVIEW 491
KEY TERMS 491 GIVE IT SOME THOUGHT 491
COMPANION WEBSITE
20 Global Climate
Change 492
Climate and Geology Are Linked 494
The Climate System 494
How Is Climate Change Detected? 496
Seafloor Sediment—A Storehouse of Climate Data 496
Oxygen Isotope Analysis 497
Climate Change Recorded in Glacial Ice 497
Other Types of Proxy Data 498
Some Atmospheric Basics 499
Composition of the Atmosphere 499
Extent and Structure of the Atmosphere 501
Heating the Atmosphere 502
Energy from the Sun 502
The Fate of Incoming Solar Energy 503
The Greenhouse Effect 504
Natural Causes of Climate Change 505
Volcanic Activity and Climate Change 505
Solar Variability and Climate 508
Human Impact on Global Climate 509
Carbon Dioxide, Trace Gases,
and Climate Change 509
CO 2 Levels Are Rising 510
The Atmosphere’ s Response 511
The Role of Trace Gases 512
Climate-Feedback Mechanisms 514
Types of Feedback Mechanisms 514
Computer Models of Climate: Important Yet
Imperfect Tools 515
How Aerosols Influence Climate 515
Some Possible Consequences
of Global Warming 516
Sea-Level Rise 516
The Changing Arctic 518
Increasing Ocean Acidity 520
The Potential for “Surprises” 520
THE CHAPTER IN REVIEW 521
KEY TERMS 522 GIVE IT SOME THOUGHT 523
COMPANION WEBSITE 523
APPENDIX A
Metric and Engligh Units Compared 475
APPENDIX B
Topographic Maps 477
APPENDIX C
Landforms of the Conterminous
United States 481
GLOSSARY 483
INDEX 493