A Brief History of the Earth's Climate , livre ebook

OF THE S E, PD
A BRIEF HISTORY
NATURE / CLIMATE CHANGE
What’s natural,
what’s caused by humans, and why A BRIEF HISTORYclimate change is a disaster for all. 
I love it. Earle understands the big climate picture and OF THEpaints it with exceptional clarity.
— JAMES HANSEN, director, Climate Science, Awareness and Solutions,
Columbia University Earth Institute
A model for clear science writing that forcefully awakens readers to
what’s at stake and what needs to be done.
— RICHARD HEINBERG, Senior Fellow, Post Carbon Institute, author, Power
A Brief History of the Earth’s Climate is an accessible myth-busting guide to the
natural evolution of the Earth’s climate over 4.6 billion years, and how and why
humancaused climate change is different and much more dangerous.
Richly-illustrated chapters cover the major historical climate change processes including
evolution of the sun, plate motions and continental collisions, volcanic eruptions, ocean
currents and cycles, sunspots, and Earth’s orbital variations, as well as human-caused
global warming. Content includes:
• Understanding natural geological processes that shaped the climate
• How human impacts are now rapidly changing the climate
• Tipping points and the unfolding climate crisis
• An overview of the implications of the COVID pandemic for climate change
• What we can do to limit the damage to the planet and ecosystems
• Countering climate myths peddled by climate change science deniers.
A Brief History of the Earth’s Climate is essential reading for everyone who is
looking to understand what drives climate change, counter skeptics and deniers, and
take action on the climate emergency.
A must-read for anyone seeking to understand the Earth’s climate system.
— ANDREW WEAVER, professor, University of Victoria, former chief editor, Journal of Climate
An engaging tour through the complex natural processes at play.
— TOM GREEN, Senior Climate Policy Advisor, David Suzuki Foundation
___________________________________________________________________
Steven Earle, PhD, has taught university Earth Science for almost four decades EVERYONE’S GUIDE toand is author of the widely used textbook, Physical Geology. He participates in
community engagement with climate change solutions on Gabriola Island, Canada, The SCIENCE of CLIMATE CHANGEwhere he lives with his family.
S E, PDwww.newsociety.comPraise for
A Brief History of the Earth’s Climate
I love it. Earle understands the big climate picture and paints it with
exceptional clarity.
— James Hansen, director, Climate Science,
Awareness and Solutions, Columbia University Earth Institute
An informative, succinct, and fascinating r — Steveaden Earle ofers
a unique and detailed account of Earth’s climate history. His innate
story-telling ability, coupled with his remarkable talent for making
complex scientifc information accessible, makes this page-turner a
must-read for anyone seeking to understand the Earth’s climate system.
— Andrew Weaver, professor, University of V ictoria,
lead author, Intergovernmental Panel on Climat e Change,
second, third, fourth, and ffth Assessment R eports,
former chief editor, Journal of Climate
An engaging tour through the complex natural processes at play in
writing the Earth’s long history of natural climate change to our present
climate emergency. This primer will give campaigners, policy makers,
and concerned citizens a more thorough understanding of climate
science and renewed conviction to go all in on applying the br - akes, leav
ing fossil fuels behind, and embracing a cleaner, healthier, and more
equitable future.
— Tom Green, Senior Climate Policy Advisor, David Suzuki Foundation
People interested in climate change, which these days should be e- very
one, need a basic understanding of the science of why Earth’s climate
is the way it is, and why it sometimes changes. Earle’s book makes that
complicated story easy to grasp. It’s a model for clear science writing,
and it forcefully awakens readers to what’s at stake and what needs to
be done. 
— Richard Heinberg, Senior Fellow, Post Carbon Institute, author, PowerA clear, concise and engaging introduction to the global ecosystem
processes that govern our climate. A fascinating read for anyone
ready to go beyond the headlines to learn more about how climate has
shaped our history, why current climate change poses an unpr - ece
dented threat to our future, and what we can do about it.
— Laura Lengnick, author, Resilient Agricul ture:
Cultivating Food Systems for a Changing ClimateA Brief History of the Earth’s ClimateA BRIEF HISTORY
OF THE
EARTH’S
CLIMATE
EVERYONE’S GUIDE to
The SCIENCE of CLIMATE CHANGE
STEVEN EARLE, PHDCopyright © 2021 by Steven Earle. All rights reserved.
Cover design by Diane McIntosh.
Cover photo: ©iStock 
All fgures, drawings, and photos by author unless otherwise noted.
Printed in Canada. First printing September, 2021.
This book is intended to be educational and informative. It is not intended to serve as a
guide. The author and publisher disclaim all responsibility for any liability, loss or risk
that may be associated with the application of any of the contents of this book.
Inquiries regarding requests to reprint all or part of A Brief History of the Earth’s Climate
should be addressed to New Society Publishers at the address below. To order directly
from the publishers, please call t free (North America) 1-oll- 800-567- 6772, or order
online at www.newsociety.com
Any other inquiries can be directed by mail to
New Society Publishers
P.O. Box 189, Gabriola Island, BC V0R 1X0, Canada
(250) 24 7- 9 737
Library and Archives Canada Cataloguing in Publication
Title: A brief history of the Earth’s climate : everyone’s
guide to the science of climate change / Steven Earle, PhD.
Names: Earle, Steven, author.
Description: Includes bibliographical references and index.
Identifers: Canadiana (print) 20210264411 | Canadiana (ebook) 20210264713 |
isbn 9780865719590 (softcover) | isbn 9781550927528 (P dF) |
isbn 9781771423489 (eP ub)
Subjects: lcsh: Climatic changes. | lc: Climatic changessh —
Efect of human beings on. | : Global wlcsh arming.
Classifcation: lcc Qc903 .e 27 2021 | ddc 363.738/74 — dc23
New Society Publishers’ mission is to publish books that contribute in fundamental
ways to building an ecologically sustainable and just society, and to do so with the least
possible impact on the environment, in a manner that models this vision. Contents
Preface ........................ ix
Acknowledgments ................... xiii
Introduction ...................... xv
1. What Controls the Earth’s Climat ...........e? 1
2. A Slowly Warming Sun................. 17
3. Sliding Plates and Colliding Continents......... 31
4. Cooling and Warming from Volcanic Eruptions ..... 43
5. Earth’s Orbital Variations................ 63
6. Moving Heat with Ocean Currents ........... 77
7. Short t -erm Solar V ariations .............. 91
8. Catastrophic Collisions ................. 103
9. A Plague of Humans .................. 115
10. Tipping Points ..................... 127
11. What Now? ...................... 147
Notes ......................... 165
Index 181
About the Author ................... 189
About New Society Publishers ............. 192
viiPreface
Let them not say: we did not see it.
We saw.
Let them not say: we did not hear it.
We heard.
Let them not say: they did not taste it.
We ate, we trembled.
Let them not say: it was not spoken, not written.
We spoke, we witnessed with voices and hands.
Let them not say: they did nothing.
We did not- enough.
— From “Let Them Not Say,” by Jane Hirshfeld 1
Climate change is not coming; it is here now. The indications are
clear, all around the world, with new ones coming t virtuallo light y
every day. One would need to have lucrative business interests, strong
political convictions, or an impressive degree of stubbornness to be
comfortable in saying that there is no strong evidence for
anthropogenic (human- caused) climat e change.
Those who do deny anthropogenic climate change often use the
argument that the climate has changed before, and in that they are
absolutely correct. The Earth’s climate has been changing one way or
another for 4.6 billion years. We have a reasonably good idea of how it
has changed, and when, and why. The main natural mechanisms are
changes in the sun’s output, evolutionary changes in the lifestyles of
organisms, moving continents and colliding tectonic plates, volcanic
ix


x Preface
eruptions, incoming comets and meteorites, and even the Earth- ’s vari
able orbit around the sun. Most of these changes have been ex- cruciat
ingly slow, but some have been —fast even faster than anthropogenic
climate change. Some are in the past, but most are still operating, and
some of those do afect our climate on a human time scale.
The premise behind this book is that in order to fully understand
anthropogenic climate change, we need to understand the Earth’s
long history of natural climate change. With just a limited knowledge
of how the sun changes, how ocean currents behave, how the Earth
wobbles (and why that matters), or how volcanic eruptions afect the
climate, we can readily see that none of these natural processes can
account for any part of the observed 1°C rise in the Earth’s average
surface temperature over the past 60 years. It’s all on us.
Knowing something about past natural climate change is crucial
to understanding the processes that are contributing t - o anthropo
genic climate change now, how the forcing mechanisms— such as in -
creased greenhouse gas le — v nudge the climatels e to a warmer state,
and how the feedback mechan — is sucmsh a s melting i —cea mp l if y
those forcings. That knowledge of past climate changes should also
help us to determine how close we are to a tipping point that could