Climate change : biological and human aspects

505 Pages·2007·5.78 MB·English

by  Jonathan Cowie.

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CLIMATE CHANGE: BIOLOGICAL AND
HUMAN ASPECTS
In recent years climate change has become recognised as the foremost envir-
onmental problem of the twenty-first century, and a subject of considerable
debate. Not only will climate change affect the multi-billion dollar energy
strategies of countries worldwide, but it could also seriously affect many
species, including our own. Written in an accessible style, this textbook pro-
videsabroadreviewofpast,presentandlikelyfutureclimatechangefromthe
viewpoints of biology, ecology and human ecology. It is thoroughly refer-
enced, allowing readers, if they wish, to embark on their own more specialist
studies.
A fascinating introduction to the subject, this textbook will be of interest
to a wide range of people, from students in the life sciences who need a brief
overview of the basics of climate science, to atmospheric science, geography
andenvironmentalsciencestudentswhoneedtounderstandthebiologicaland
human ecological implications of climate change. It will also be a valuable
reference for those invol ved in environmental monitoring, conservation,
policy-makingandpolicylobbying.
JONATHAN COWIE hasspent many years conveyingthe viewsof biological
science learned societies to policy-makers. His earlier postgraduate studies
related to energy and the environment, and he is a former Head of Science
PolicyandBooksattheInstituteofBiology(UK).HeisauthorofClimateand
HumanChange:DisasterorOpportunity(ParthenonPublishing,1998).

CLIMATE CHANGE
Biological and Human Aspects
JONATHAN COWIE
CAMBRIDGE UNIVERSITY PRESS
Cambridge, New York, Melbourne, Madrid, Cape Town, Singapore, São Paulo
Cambridge University Press
The Edinburgh Building, Cambridge CB2 8RU, UK
Published in the United States of America by Cambridge University Press, New York
www.cambridge.org
Information on this title: www.cambridge.org/9780521696197
© J. Cowie 2007
This publication is in copyright. Subject to statutory exception and to the
provision of relevant collective licensing agreements, no reproduction of any part
may take place without the written permission of Cambridge University Press.
First published in print format 2007
ISBN-13 978-0-511-55673-9 eBook (Dawsonera)
ISBN-13 978-0-521-69619-7 paperback
Cambridge University Press has no responsibility for the persistence or accuracy
of urls for external or third-party internet websites referred to in this publication,
and does not guarantee that any content on such websites is, or will remain,
accurate or appropriate.
Contents
Introduction pagexi
Acknowledgements xv
1 Anintroductiontoclimatechange 1
1.1 Weatherorclimate 2
1.2 Thegreenhouseeffect 3
1.3 Thecarboncycle 10
1.4 Naturalchangesinthecarboncycle 20
1.5 Pacemakeroftheglacial–interglacialcycles 22
1.6 Non-greenhouseinfluencesonclimate 28
1.7 Thewatercycle,climatechangeandbiology 31
1.8 Fromtheorytoreality 33
1.9 References 35
2 Principalindicatorsofpastclimates 37
2.1 Terrestrialbioticclimaticproxies 39
2.1.1 Tree-ringanalysis(dendrochronology) 39
2.1.2 Isotopicdendrochronology 43
2.1.3 Leafshape (morphology) 45
2.1.4 Leafphysiology 46
2.1.5 Pollenandsporeanalysis 47
2.1.6 Speciesasclimateproxies 50
2.2 Marinebioticclimaticproxies 53
2.2.1 18Oisotopeanalysisofforamsandcorals 53
2.2.2 Alkenoneanalysis 58
2.3 Non-bioticindicators 59
2.3.1 Isotopicanalysisofwater 59
2.3.2 Boreholes 61
2.3.3 Carbondioxideandmethanerecordsas
palaeoclimaticforcingagents 61
2.3.4 Dustasanindicatorofdry–wethemisphericclimates 63
2.4 Otherindicators 63
v
vi Contents
2.5 Interpretingindicators 64
2.6 Conclusions 64
2.7 References 65
3 Pastclimatechange 67
3.1 EarlybiologyandclimateoftheHadeanandArcheaen
eons(4.6–2.5billionyearsago,bya) 67
3.1.1 Thepre-bioticEarth(4.6–3.8bya) 67
3.1.2 TheearlybioticEarth(3.8–2.3bya) 68
3.2 Majorbio-climaticeventsoftheProterozoiceon
(2.5–0.542bya) 71
3.2.1 Earthintheanaerobic–aerobictransition
(2.6–1.7bya) 71
3.2.2 TheaerobicEarth(from1.7bya) 74
3.3 Majorbio-climaticeventsofthepre-QuaternaryPhanerozoic
(540–2mya) 77
3.3.1 Late-Ordovicianextinction(455–435mya) 77
3.3.2 Late-Devonianextinction(365–363.5mya) 78
3.3.3 Vascularplantsandtheatmosphericdepletion
ofcarbondioxide(350–275mya) 79
3.3.4 Permo–Carboniferousglaciation(330–250mya) 81
3.3.5 End-Permianextinction(251mya) 83
3.3.6 End-Triassicextinction(205mya) 85
3.3.7 Toarcian(early(latelower)Jurassic)extinction
(183mya) 86
3.3.8 Cretaceous–Tertiaryextinction(65.5mya) 87
3.3.9 Eoceneclimaticmaximum(55–54.8mya) 90
3.3.10 Eocene–O ligoceneextinction(approximately35mya;
or33.9mya?) 101
3.3.11 LateMioceneexpansionofC grasses(14–9mya) 103
4
3.4 Summary 108
3.5 References 109
4 TheOligocenetotheQuaternary:climateandbiology 113
4.1 TheOligocene(33.9–23.03mya) 113
4.2 TheendMiocene(9–5.3mya) 115
4.3 ThePliocene(5.3–1.8mya) 116
4.4 Thecurrenticeage 120
4.5 Thelastglacial 126
4.5.1 Overviewoftemperature,carbondioxideandtiming 126
4.5.2 Iceandsealevel 129
4.5.3 Temperaturechangeswithintheglacial 130
Contents vii
4.5.4 Biologicalandenvironmentalimpactsofthelastglacial 141
4.6 Interglacialsandthepresentclimate 148
4.6.1 Previousinterglacials 148
4.6.2 TheAllerød,BøllingandYoungerDryas
(14600–11600yearsago) 152
4.6.3 TheHolocene(11500yearsago–theIndustrial
Revolution) 159
4.6.4 Biologicalresponsetothelastglacial,LGMand
Holocenetransition 168
4.7 Summary 178
4.8 References 179
5 Presentclimateandbiologicalchange 184
5.1 Recentclimatechange 184
5.1.1 ThelatterhalfoftheLittleIceAge 184
5.1.2 Twentieth-centuryclimate 188
5.1.3 Twenty-first-centuryclimate 189
5.1.4 TheHoloceneinterglacialbeyondthetwenty-first
century 189
5.1.5 Holocenesummary 191
5.2 HumanchangearisingfromtheHoloceneclimate 193
5.2.1 Climaticimpactsonearlyhumancivilisations 193
5.2.2 TheLittleIceAge’shumanimpact 194
5.2.3 Increasingtwentieth-centuryhumanclimatic
insulation 200
5.3 Climateandbusinessasusualinthetwenty-firstcentury 201
5.3.1 IPCCBusinessasUsual 201
5.3.2 Uncertaint iesandtheIPCC’sconclusions 213
5.4 Currenthumaninfluencesonthecarboncycle 222
5.4.1 Carbondioxide 222
5.4.2 Methane 226
5.4.3 Halocarbons 227
5.4.4 Nitrousoxide 228
5.5 References 228
6 Currentwarmingandlikelyfutureimpacts 231
6.1 Currentbiologicalsymptomsofwarming 231
6.1.1 Currentborealdendrochronologicalresponse 231
6.1.2 Currenttropical-rainforestresponse 233
6.1.3 Somebiologicaldimensionsoftheclimatic-change
fingerprint 235
6.1.4 Phenology 238
viii Contents
6.1.5 Biologicalcommunitiesandspeciesshift 240
6.2 Casestudy:climateandnaturalsystemsintheUSA 253
6.3 Casestudy:climateandnaturalsystemsintheUK 264
6.4 Biologicalresponsetogreenhousetrendsbeyondthe
twenty-firstcentury 275
6.5 Possiblesurpriseresponsestogreenhousetrendsinthe
twenty-firstcenturyandbeyond 276
6.5.1 Extremeweatherevents 276
6.5.2 Greenhousegases 279
6.5.3 Sea-levelrise 280
6.5.4 Methanehydrates(methaneclathrates) 289
6.5.5 Volcanoes 293
6.5.6 Oceanicandatmosphericcirculation 296
6.5.7 Oceanacidity 301
6.5.8 Theprobabilityofsurprises 304
6.6 References 305
7 Thehumanecologyofclimatechange 310
7.1 Population(past,presentandfuture)andits
environmentalimpact 310
7.1.1 Populationandenvironmentalimpact 310
7.1.2 Pastandpresentpopulation 319
7.1.3 Futurepopulation 322
7.1.4 Food 325
7.1.5 Impactonotherspecies 327
7.2 Energysupply 330
7.2.1 Energysupply–thehistoricalcontext 331
7.2.2 Futureene rgysupply 337
7.3 Humanhealthandclimatechange 343
7.3.1 Healthandweatherextremes 345
7.3.2 Climatechangeanddisease 353
7.3.3 Floodingandhealth 361
7.3.4 Droughts 368
7.4 Climatechangeandfoodsecurity 368
7.4.1 Pastandpresentfoodsecurity 368
7.4.2 Futurefoodsecurityandclimatechange 371
7.5 Thebiologyofreducinganthropogenicclimatechange 377
7.5.1 Terrestrialphotosynthesisandsoilcarbon 378
7.5.2 Manipulatingmarinephotosynthesis 383
7.5.3 Biofuels 384
7.6 Summaryandconclusions 387