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The Geomorphology of the Great Barrier Reef
Development, Diversity, and Change
By David Hopley, Scott G. Smithers,
and Kevin E. Parnell, Cambridge
University Press, 2007, 546 pages, ISBN
9780521853026, Hardcover, $150 US
REVIEWED BY NICK HARVEY
The Geomorphology of the Great Barrier
Reef by David Hopley, Scott G. Smithers,
and Kevin E. Parnell was preceded
25 years ago by Hopley’s landmark
book on the same topic. The first book
filled a void in terms of Quaternary
reef science at the time, and the recent
volume provides a fresh perspective on
the complexity, diversity, and volume of
geomorphological research undertaken
on the Great Barrier Reef (GBR) over
the last 25 years. To complete this task,
Hopley teamed up with two other
coastal geomorphologists, Smithers
and Parnell, both based at James Cook
University in North Queensland. The
three authors have extensive experience
in reef research and are well qualified to
write this book.
The book is aimed at “academic
researchers in geomorphology and
oceanography” and is also intended to
appeal “to graduate students in related
fields.” The 468-page text is organized
into 13 well-illustrated chapters that
include over 150 black-and-white line
diagrams and photographs. Although the
diagrams are well drawn and clear, many
of them, and most of the photographs,
would have benefited considerably from
being reproduced in color (I have seen
some of the original photographs, which
are quite spectacular). This publishing
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Oceanography
Vol.21, No.1
decision was undoubtedly cost-related.
The book’s chapters are basically
organized into three groups. The first
group of four chapters provides the
background to the geomorphology of the
GBR including a historical perspective
on previous research, the geological
background, the impact of Quaternary
sea-level changes, and the influence of
oceanography, hydrodynamics, climate,
and water quality. The next group of six
chapters (5–10) takes a spatial approach
in terms of an overall analysis of reef
and island morphology (Chapter 5),
and also deals with different areas of the
reef in separate chapters such as those
treating the mid-shelf reefs (Chapter 8)
and the reef islands (Chapter 10). The
final group of three chapters (11–13)
synthesizes some of the earlier material
and discusses it in a broader context. For
example, Chapter 11 compares processes
and rates from all the reef types and then
puts them in context with examples from
reefs located elsewhere. Chapter 13 summarizes the usefulness of geomorphology in GBR management.
The discussion on the foundations
of the reef (Chapter 2) shows that the
modern GBR is one of the world’s
youngest reef systems and that the major
reef-building turn-on event occurred
between 452 and 365 thousand years ago.
However, the geomorphological characteristics of the GBR are mostly related to
the last glacial period lasting for around
100 thousand years when the reef was
exposed and subsequently drowned
rapidly during the Holocene sea-level
transgression. Chapter 3 goes into some
detail regarding the importance of
sea-level fluctuations in controlling reef
growth, and it points out that the GBR
was subject to long periods of subaerial
exposure with only relatively short
intervening periods of reef construction.
This chapter also provides a detailed discussion on the debate around Holocene
sea-level curves for the GBR region, in
particular the issues of whether there
was a smooth or pulsed sea-level rise,
the date at which modern sea level was
reached, the influence of hydro-isostasy,
and the complications of using sea-level
data from different sea-level indicators
and from different parts of the GBR.
The next chapter, which outlines
the importance of climatological and
hydrodynamic influences on the GBR,
comments that the modern debate on
climate-change impacts needs to be in
the context of the variability of the last
few hundred years when climatic cycles
such as the El Niño Southern Oscillation
(ENSO) have been important factors.
Similarly, the chapter notes the lack of
Category 5 cyclones in the twentieth
century compared to severe cyclogenesis
in the nineteenth century based on
This article has been published in Oceanography, Volume 21, Number 1, a quarterly journal of The Oceanography Society. Copyright 2008 by The Oceanography Society. All rights reserved. Permission is granted to copy this article for use in teaching and research. Republication, systemmatic reproduction,
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B o o k R eviews
geomorphological evidence. This observation illustrates well the importance
of geomorphological data to extend the
historical record and avoid misinterpretations based on the relatively short
instrumental record. Chapter 4 also
provides an overview of water, sediment,
and nutrient impacts on the GBR.
Chapter 5 is the first of six chapters
that provides a spatial approach to
explaining patterns of reef morphology
throughout the GBR region. This chapter
goes into some detail, supplying reef and
reef-island statistics, and descriptions
of classification and distribution of reefs
by type (e.g., crescentic or ribbon reefs).
The chapter demonstrates the nonrandomness of reef type distribution
and sets the scene for the following five
chapters, which examine reef evolution
of: non-reefal areas (Chapter 6); fringing and nearshore reefs (Chapter 7);
mid-shelf reefs (Chapter 8); outer-shelf
reefs (Chapter 9); and the islands
(Chapter 10). Each chapter has a different focus, such as the substrate and
deposits of fringing reefs in Chapter 7,
and the shelf-edge morphology of and
tectonic influences on the outer-shelf
reefs in Chapter 9.
Chapters 11 and 12 take a more
holistic approach to GBR evolution by
discussing data from all the reefs in the
GBR to provide a better understanding
of rates of geomorphological processes
across the GBR and also in context of
other reefs in different parts of the world.
For example, Chapter 11 examines
variations in the depth to the antecedent
surface on the GBR (4–28 meters) and
notes the similar depth range of this
antecedent surface for other Australian
reefs and also for Pacific atolls. This
chapter discusses models of reef growth
in response to different rates of sea-level
rise and the different growth rates for
various reef facies. In particular, it notes
the importance of the antecedent surface
structure for the take-off rate and timing
of Holocene reef growth but stresses
the importance of the relative sea-level
curve in influencing reef facies, growth
rates, and age of the near-surface reef.
Here, the chapter shows how the reef
reaches optimal vertical growth rates
of ~ 8 mm per year at water depths of
12 to 15 meters and discusses how various reefs in the GBR either kept up with
sea-level rise or got left behind and managed to catch up later after sea level had
stabilized. This discussion is important
when considering future reef response
to projected sea-level rise associated
with climate change. The chapter is also
important for its comparison between
the GBR, Indo-Pacific atolls, Pacific
barrier and fringing reefs, Indian Ocean
reefs, and Caribbean reefs.
The following chapter (12) then
provides a synthesis of the Holocene
evolution of the GBR by discussing key
upcoming
stages, such as the glacial maximum low
sea level, the early sea-level transgression, the start of the Holocene, the final
stage of the transgression, and then
the mid-to-late Holocene. This chapter
paints a picture of what the continental
shelf would have looked like at various
stages through the Holocene and notes
that Aboriginal people in Australia
were present throughout the flooding
of the continental shelf and the creation
of the modern GBR.
The final chapter focuses on the
importance of understanding geomorphological processes for management
and conservation of the GBR. It is unfortunate that its running header emphasizes “Geomorphology’s contribution to
the problems of the Great Barrier Reef ”
rather than the importance of geomorphological knowledge to understanding
and solving the problems. This chapter
provides useful data on reef islands,
sediments, nutrients, geomorphology, and conservation, but notes that
geomorphological criteria have mostly
been given a low status in the manage-
BOOK Reviews
Ebb and Flow: Tides and Life on our Planet
by Tom Koppel, The Dundern Group, 292 pages
Lagrangian Analysis and Prediction of Coastal and Ocean Dynamics
by A. Griffa, A.D. Kirwan Jr., A.J. Mariano, T. Özgökmen, and T. Rossby,
Cambridge University Press, 487 pages
Climate Change: A Multidisciplinary Approach
by William James Burroughs, Cambridge University Press, 378 pages.
Arc Marine: GIS for a Blue Planet
by Dawn J. Wright, Michael J. Blongewicz, Patrick N. Halpin, and Joe Breman,
ESRI Press, 216 pages
Oceanography
March 2008
111
ment of the GBR compared with many
terrestrial national parks. The final part
of this chapter reflects on the importance
of global climate change and the impact
of projected sea-level rise on the GBR
from a geomorphological perspective.
This discussion is very relevant for the
current global debate on the impacts
of climate change such as the Fourth
Assessment of the Intergovernmental
Panel on Climate Change (IPCC), in
particular the report from Working
Group II (Parry et al., 2007). At the
regional level, this issue is also addressed
in the recent volume on Climate Change
and the Great Barrier Reef (Johnson and
Marshall, 2007), which incorporates a
detailed discussion on potential geo-
morphological impacts resulting from
climate change on the GBR.
Overall, I think the book is an excellent synthesis of current knowledge on
the geomorphology of the Great Barrier
Reef. While I agree with the authors that
understanding geomorphological reef
processes is very important in the management of the GBR, I don’t think that
this book alone will convince managers
of that need because it is largely written
for a different target audience. However,
the book will undoubtedly become an
essential reference for reef researchers
and graduate students, and I give it my
strongest endorsement. I congratulate
the three authors on producing such a
comprehensive text.
N ick H arvey (nicholas.harvey@
adelaide.edu.au) is the Executive Dean,
Faculty of Humanities and Social
Sciences, and Professor, Geography and
Environmental Studies, The University of
Adelaide, South Australia.
REFERENCE S
Parry, M.L., O.F. Canziani, J.P. Palutikof, P.J. van der
Linden, and C.D. Hansen, eds. 2007. Climate
Change 2007: Impacts, Adaptation and Vulnerability.
Contribution of Working Group II to the Fourth
Assessment Report of the Intergovernmental Panel
on Climate Change. Cambridge University Press,
Cambridge, UK, 1000 pp.
Johnson, J.E., and P.A. Marshall, eds. 2007. Climate
Change and the Great Barrier Reef: A Vulnerability
Assessment. Great Barrier Reef Marine Park
Authority and Australian Greenhouse Office.
818 pp.
The Unnatural History of the Sea
We learn from history that we do not learn from history.
—Georg Wilhelm Friedrich Hegel (1770–1831)
By Callum M. Roberts, Island Press,
2007, 435 pages, ISBN 9781597261029,
Hardcover, $28.00 US
REVIEWED BY ANDREW J. READ
On June 15, 2006, President George
W. Bush created the world’s largest
fully protected marine reserve, the
Papahānaumokuākea Marine National
Monument in the Northwestern
Hawaiian Islands (NWHI). Established
by Presidential proclamation, the monument is the largest conservation area in
the United States. In his proclamation
speech, the president noted that, “our
duty is to use the land and seas wisely, or
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Vol.21, No.1
sometimes not use them at all.”
Coming, as it did, from a president
not known for his sensitivity to environmental issues, the establishment of the
Papahānaumokuākea Marine National
Monument was a major victory for the
conservation of marine ecosystems.
Commercial fisheries, and other forms
of resource extraction, are to be banned
from the monument, providing an
unparalleled level of protection to the
fragile coral reef ecosystems of the
NWHI. Coral reefs are often described
as the rainforests of the sea because of
their biodiversity and, in some areas,
high levels of endemism.
Throughout the world ocean, coral
reefs are in decline, due to the synergistic
effects of overfishing, coastal development, and climate change. One of the
most pervasive threats is overfishing,
particularly of large, predatory fishes.
In one stroke of his pen, President Bush
eliminated this threat to the extensive
coral reef systems in the NWHI. But
what of coral reef systems elsewhere in
the world? And what about the effects
of fishing on other, less-celebrated
marine ecosystems?
To answer these questions, Callum
Roberts has written The Unnatural
History of the Sea, which he describes as
“…an account of the history of fishing
and the effects it has had on the sea.” The
book is encyclopedic in scope, starting
with the earliest accounts of fishing in
the medieval period and continuing to
the present. Roberts covers the history of
European and North American harvests
of whales, seals, sea turtles, oysters, and
fish and the effect of these removals on
marine ecosystems.
The history of many fisheries, as
seen through Roberts’ long historical
lens, is depressingly familiar. The initial
discovery of a new resource is followed
by a rapid and profitable harvest expansion, which leads to overcapitalization,
excess harvesting capacity, and eventual
collapse of both the resource and the
fishery. Roberts argues, correctly in my
view, that to fully understand the effects
of marine fisheries, we need to compare
the current status of marine ecosystems
with their structures and compositions
prior to exploitation. But this is a difficult task, as most marine ecosystems
were first exploited long before the fields
of marine ecology and fisheries biology
were conceived. Intensive fisheries have
existed in Europe for centuries, but systematic observations of fisheries and fish
populations (using fisheries-independent
data) began only at the dawn of the
twentieth century. Thus, when we examine trend data on the abundance of an
exploited population, the starting point
of our time series may not be representa-
tive of pre-exploitation conditions. This
gap in our knowledge is exacerbated by
the problem of shifting baselines, a term
coined by Daniel Pauly of the University
of British Columbia, which describes the
tendency of each scientist to evaluate
the degradation of marine ecosystems
over her or his lifetime, thus ratcheting down expectations of ecosystem
structure and function.
One of the great strengths of The
Unnatural History of the Sea is the use
of older sources. The first third of this
book, entitled “Explorers and Exploiters
in the Age of Plenty,” is replete with citations to antique volumes. In the preface,
Roberts admits to “an incurable passion
for dusty, ancient tomes,” and the reader
is all the better for his obsession. Later
in the book, Roberts describes some of
the first reviews of the ecological effects
of commercial fishing, including a
British Royal Commission appointed to
examine the effects of bottom trawling
in 1863. The excerpts of the Commission
report will make sadly familiar reading
to anyone acquainted with today’s battles
over fisheries conservation in Europe
or North America.
Any book of this scope will contain
some shortcomings and a few errors, and
The Unnatural History of the Sea is no
exception. Roberts does not give much
consideration to opposing points of view
and occasionally presents controversial
hypotheses without an adequate explanation of the uncertainty associated with
these ideas. Nevertheless, the book is a
call to action rather than a dry, scholarly
account of divergent viewpoints, and
I have no quarrel with any of Roberts’
fundamental conclusions.
In the last third of the book, Roberts
lays out a series of recommendations
for the reform of fisheries management.
He does so in a nontechnical and very
accessible fashion, in keeping with the
rest of the book. He identifies seven
specific areas of reform that he believes
are necessary to create sustainable (and
more profitable) fisheries: (1) reduce the
amount of fishing, (2) eliminate risky
decisions, (3) eliminate catch quotas,
(4) require fishers to keep what they
catch, (5) use the best available fishing
technology to reduce bycatch, (6) ban
or restrict the most damaging fishing
gear, and (7) implement extensive
networks of marine reserves that are off
limits to fishing. Roberts is best known
for his work on marine reserves and
he makes a strong argument for their
efficacy in improving fish yields and
conserving biodiversity.
I read Callum Roberts’ book while
taking a graduate class in Marine
Conservation Biology to Midway Atoll in
the newly created Papahānaumokuākea
Marine National Monument. After the
experience of snorkeling in a small
marine reserve near Honolulu, my students and I were amazed to see the abundance and size of reef fish at Midway.
It was a profound experience to swim
alongside enormous jacks and through
huge schools of goatfish. Perhaps
Roberts’ book, and his optimism, will
help to prove Hegel wrong. I hope so.
ANDREW J. READ ([email protected])
is Rachel Carson Associate Professor
of Marine Conservation Biology,
Nicholas School of the Environment
and Earth Sciences, Duke University,
Beaufort, NC, USA.
Oceanography
March 2008
113
Fundamentals of
Geophysical Fluid Dynamics
By James C. McWilliams, Cambridge
University Press, 2006, 266 pages,
ISBN 9780521856379, Hardcover,
$79 US
Reviewed by Christopher
A. Edwards
Fundamentals of Geophysical Fluid
Dynamics is a new textbook that
provides an introduction to the basic
dynamics governing fluid motion in a
rotating system. This book is designed
for first-year graduate students and
assumes background knowledge of
multivariable calculus, partial differential
equations, and classical mechanics. It
would also be helpful if a student had
previously studied nonrotational fluid
dynamics and more general phenomenology of the ocean and atmosphere.
The text is divided into six chapters. A
very short introduction sets the broader
context for the book’s subject. The
second chapter presents a limited discussion of the basic equations that govern
fluid dynamics, for example, those for
conservation of momentum and kinetic
and potential energy, and it introduces
concepts of divergence, circulation, and
vorticity. This chapter also provides
relevant fundamentals, such as the equations of state and observed stratification
for the ocean and the atmosphere. The
final section of this chapter focuses on
the influence of rotation, introducing
geostrophic balance and including a
valuable discussion of scaling to identify
appropriate limits for approximations.
114
Oceanography
Vol.21, No.1
The third chapter, entitled “Barotropic
and Vortex Dynamics,” addresses twodimensional motion in the horizontal
plane only. This chapter begins with
the barotropic equations and defines
the appropriate forms of the vorticity equation, potential vorticity, and
streamfunction. By reintroducing
geostrophy and extending the discussion
to gradient-wind balance, the author
prepares for an extensive discussion of
stationary vortex flow and movement of
multiple vortices. The chapter includes
a section on barotropic and centrifugal
instability, and concludes with a section on two-dimensional turbulence,
with a concise discussion of the energy
and enstrophy cascades. This chapter’s
emphasis on vortex processes is excellent
and unique among existing geophysical
fluid dynamics texts. Providing this
emphasis adds meaningfully to existing
resources for students with material
that extends easily across multiple
geophysical systems.
The topic of Chapter 4 is rotating
shallow-water and wave dynamics. It
begins with classical discussions of
linear wave solutions and geostrophic
adjustment, but then expands into
nonlinear wave steepening leading
to wave breaking. After an introduction to quasigeostrophy, the chapter
discusses Rossby waves and ends with
mechanisms for their generation. In
general, the author very clearly does not
try to exhaustively cover all aspects of
geophysical fluid dynamics, particularly
when a subject is discussed extensively in
other texts. Rather, he includes sufficient
information to make this text (and associated course) self-contained, and directs
interested readers to other references
for further study. The author’s treatment
of linear waves in geophysical systems
is an excellent example. The text solidly
addresses many introductory aspects and
then moves on to important extensions,
for example, nonlinear bores and the
coupling of vortices on the beta-plane
to Rossby wave modes, which are not
covered in commonly used geophysical
fluid dynamics texts.
Chapter 5 introduces baroclinic
motion with layered hydrostatic models.
The chapter’s central topic, baroclinic
instability, is covered in two parts. The
first part is an analytical treatment
of two-layer flow, described using a
normal-mode approach. The second
part describes the processes resulting
from instability of a three-layer zonal jet.
This section draws heavily on numerical
experiments carried out by the author
decades ago, but provides useful,
intuition-building ideas about eddymean flow interaction and along- and
cross-jet balances.
The final chapter focuses on boundary
layers and the physics of ocean gyres. It
derives appropriate dynamical approximations for atmospheric planetary
boundary layers and surface and bottom
boundary layers in the ocean. There is a
subsequent discussion of classical winddriven ocean gyres. Both of these sections include interesting and important
material focused on numerical support
for the analytical treatments provided. In
particular, there is a discussion of direct
numerical simulations to test the validity
of Ekman theory. In addition, the author
uses scaling arguments to alert the
student that real ocean gyres are more
nonlinear than classical theory demands.
He presents numerical experiments to
reveal the influence of such nonlinearity.
Overall, this textbook is extremely
successful as a reference for an introductory graduate course. It balances
two goals: discussing a wide range of
interesting topics to engage the student
reader and providing sufficient depth to
offer students a rigorous foundation. By
presenting relevant images of oceanic
or atmospheric features, each chapter
begins with classical material for which
analytic approaches apply; each subject
ends with more realistic, nonlinear
regimes explored usually using idealized
numerical output for phenomenological
description or further analysis. There is
some uneven treatment, for example, the
discussion of the rotational coordinate
transformation and the introduction to
the N-layer system, but these areas are
very few in number. The book’s scope is
limited, omitting, for example, dynamics of internal waves in a continuously
stratified medium, but it includes more
than enough material for an introductory course—which is its intent. The
book is systematically organized, and the
exposition is extremely clear and chock
full of short, effective definitions and
illuminating descriptions of important
geophysical processes. On top of this,
the text includes a collection of useful
and challenging problems that are
perfect for a class. These problems fill out
derivations not offered in the text and
also extend material and ideas brought
forth within the chapters. Their inclusion
further helps make this text an excellent
teaching resource.
In summary, Fundamentals of
Geophysical Fluid Dynamics is a valuable
addition to the existing collection of
texts in this field. It is a well-written,
concisely worded, self-contained introduction, emphasizing material, such as
vortex motion, not central to other texts
of its type. It will be useful as a study
guide to incoming graduate students as
well as an occasional reference for more
advanced researchers in the field.
Christopher A. Edwards (cedwards@ucsc.
edu) is Assistant Professor, Ocean Sciences
Department, University of California,
Santa Cruz, CA, USA.
Upcoming
Special-Issue
Topics
Vol. 21, No. 2, June 2008
Celebrating 50 Years of International
Partnerships in Ocean Research
Guest Editor: Peter Ranelli,
NATO Undersea Research Centre
Vol. 21, No. 3, September 2008
20th Anniversary of
The Oceanography Society
Guest Editor: Melbourne Briscoe,
founding Secretary of TOS
Vol. 21, No. 4, December 2008
Coastal Ocean Processes
Guest Editor: Richard Jahnke,
Skidaway Institute of Oceanography
Vol. 22, No. 1, March 2009
HERMES: Hotspot Ecosystem Research on
the Margins of European Seas
Guest Editors: TBN
Vol. 22, No. 2, June 2009
Tenth Anniversary of the National
Oceanographic Partnership Program
Guest Editors: Eric Lindstrom, National
Aeronautics and Space Administration;
Jim Kendall, Minerals Management
Service; and Ben Chicoski, Consortium
for Ocean Leadership
Vol. 22, No. 3, September 2009
The Revolution in Global Ocean Forecasting
– GODAE: 10 Years of Achievement
Guest Editors: Mike Bell, National Centre for
Ocean Forecasting, and Pierre-Yves Le Traon,
IFREMER
Vol. 22, No. 4, December 2009
Ocean Acidification
Guest Editor: Richard Feely, National Oceanic
and Atmospheric Administration
Future Topic
Future of Satellite Oceanography
The editorial staff also encourages unsolicited
manuscripts on other oceanography themes
for consideration and publication under the
Regular Features banner.
Oceanography
March 2008
115