The Long Thaw: How Humans Are Changing the Next 100,000 Years of Earth's Climate (Science Essentials)

193 Pages·2010·0.97 MB·English

by  David Archer

THE
LONG
THAW
BooksintheSCIENCEESSENTIALSseriesbring
cutting-edgesciencetoageneralaudience.The
seriesprovidesthefoundationforabetterunder-
standingofthescientificandtechnicaladvances
changingourworld.Ineachvolume,aprominent
scientist—chosenbyanadvisoryboardofNational
AcademyofSciencesmembers—conveysinclear
prosethefundamentalknowledgeunderlyinga
rapidlyevolvingfieldofscientificendeavor.
TheGreatBrainDebate:NatureorNurture,
byJohnDowling
Memory:TheKeytoConsciousness,
byRichardF.Thompsonand
StephenMadigan
TheFacesofTerrorism:SocialandPsychological
Dimensions,
byNeilJ.Smelser
TheMysteryoftheMissingAntimatter,
byHelenR.QuinnandYossiNir
TheLongThaw:HowHumansAreChangingthe
Next100,000YearsofEarth’sClimate,
byDavidArcher
TheMedeaHypothesis:IsLifeonEarth
UltimatelySelf-Destructive?
byPeterWard
HowtoFindaHabitablePlanet,
byJamesKasting
TheLittleBookofStringTheory,
byStevenS.Gubser
DAVID ARCHER
THE
LONG
THAW
How Humans Are Changing the Next
100,000 Years of Earth's Climate
PrincetonUniversityPress
PrincetonandOxford
Copyright(cid:148)2009byPrincetonUniversityPress
PublishedbyPrincetonUniversityPress,
41WilliamStreet,
Princeton,NewJersey08540
IntheUnitedKingdom:PrincetonUniversityPress,
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OxfordshireOX201TW
press.princeton.edu
AllRightsReserved
Fourthprinting,andfirstpaperbackprinting,2010
PaperbackISBN:978-0-691-14811-3
ClothISBN:978-0-691-13654-7
LibraryofCongressControlNumber:2008931528
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andImpact
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PrintedintheUnitedStatesofAmerica
5 7 9 10 8 6 4
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Contents
Acknowledgments xi
Prologue. Global WarminginGeologicTime.
An overview of the thrust of the book: human-induced
climate change in the context of geologic time, in the past
and in the future. 1
SECTION I. THE PRESENT
Chapter1.TheGreenhouseEffect.
Fourier and greenhouse theory. Early CO measurements.
2
Arrhenius and the forecast. Climate science since then. 15
Chapter 2. We'veSeenItwithOur OwnEyes.
Testing the forecast. Impacts already. 30
Chapter 3. Forecast of theCentury.
A century-timescale climate spike. Temperature,
rainfall, sea level, and storms. 45
viii ■ CONTENTS
SECTION II. THE PAST
Chapter 4. Millennial ClimateCycles.
Abrupt climate transitions, and climate cycles on
millennial timescales. The Little Ice Age and the
Medieval Optimum climates. 57
Chapter 5. GlacialClimate Cycles.
History of their discovery. Ice flows and melts in
quirky ways. Orbital forcing and CO forcing. 69
2
Chapter 6. Geologic ClimateCycles.
Our ice age is unusual. The Earth is breathing. 78
Chapter 7. ThePresent in theBosom of thePast.
Climate change so far and in the coming century,
compared with deglaciation, abrupt climate change,
the Eocene hothouse, the Paleocene/Eocene thermal
maximum event, and the K/T boundary. 91
SECTION III. THE FUTURE
Chapter 8. TheFateofFossilFuelCO
2.
Reservoirs of carbon, breathing. New carbon from
fossil fuels equilibrates with the ocean and the land. 101
Chapter 9. Acidifying theOcean.
CO is an acid. CaCO is a base. Neutralization takes
2 3
millennia. CO remains higher than natural for hundreds
2
of millennia. 114
Chapter 10.CarbonCycle Feedbacks.
The short-term prognosis. The long-term prognosis. 125
CONTENTS ■ ix
Chapter 11.Sea Levelinthe Deep Future.
If the past is the key to the future, we have the capacity
to raise sea level by 50 meters, eventually. 137
Chapter 12.Orbits, CO , andthe Next IceAge.
2
Interplay between orbital and CO climate forcings.
2
The next ice age is about to be canceled. 149
Epilogue. Carbon Economicsand Ethics.
What the options are and how we decide. 158
Further Reading 175
Index 179