The Climate Modelling Primer E-Book

Kendal McGuffie

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 859

Veröffentlichungsjahr: 2014

Beschreibung

As a consequence of recent increased awareness of the social and political dimensions of climate, many non-specialists discover a need for information about the variety of available climate models. A Climate Modelling Primer, Fourth Edition is designed to explain the basis and mechanisms of all types of current physically-based climate models.

A thoroughly revised and updated edition, this book will assist the reader in understanding the complexities and applicabilities of today’s wide range of climate models. Topics covered include the latest techniques for modelling the coupled biosphere-ocean-atmosphere system, information on current practical aspects of climate modelling and ways to evaluate and exploit the results, discussion of Earth System Models of Intermediate Complexity (EMICs), and interactive exercises based on Energy Balance Model (EBM) and the Daisyworld model. Source codes and results from a range of model types allows readers to make their own climate simulations and to view the results of the latest high resolution models. Now in full colour throughout and with the addition of cartoons to enhance student understanding the new edition of this successful textbook enables the student to tackle the difficult subject of climate modeling.

Leseprobe

CONTENTS

PREFACE

Learning Objectives – for the whole book

Illustrative climate model understanding boxes

Technical/mathematical boxes

Practical communication about climate modelling: learning by doing

A, B, C to R, S, T of climate modelling

Downloadable, easy-to-use climate models to explore concepts

Biographies of people who are/have been important in climate modelling

Chapter summary

Chapter closing showcase

ACKNOWLEDGEMENTS

ABOUT THE COMPANION WEBSITE

1 Why Model Climate?

1.1 Introduction

1.2 What is a climate model?

1.3 Multiple reasons for climate modelling

1.4 Climate models: sound components in careful combination

1.5 Climate modelling: about this book

1.6 Summary: research and review

2 The Evolution of Climate Models

2.1 Introducing climate modelling

2.2 Types of climate models

2.3 History of climate modelling

2.4 Sensitivity of climate models

2.5 Parameterisation of climatic processes

2.6 Simulation of the full, interacting climate system: one goal of modelling

2.7 Summary: research and review

3 Energy Balance Models

3.1 Balancing the planetary radiation budget

3.2 The structure of energy balance models

3.3 Parameterising the climate system for energy balance models

3.4 Simple climate models

3.5 Energy balance and glacier models

3.6 Box models – another form of energy balance model

3.7 Energy balance models: deceptively simple

3.8 Summary: research and review

4 Intermediate Complexity Models

4.1 Why lower complexity?

4.2 One-dimensional radiative-convective models

4.3 Radiation: the driver of climate

4.4 Experiments with radiative-convective models

4.5 Reduced complexity models

4.6 The spectrum of Earth system models of intermediate complexity

4.7 Why are some climate modellers Flatlanders?

4.8 Summary: research and review

5 Coupled Climate System Models

5.1 Three-dimensional models of the climate system

5.2 Configuring the climate

5.3 Computers for modelling climate

5.4 Modelling climate components

5.5 Localising climate models

5.6 ‘Complete’ coupled climate models

5.7 Summary: research and review

6 Through the Looking Glass

6.1 First reflection: a chef or a modeller?

6.2 Second reflection: knowledge ‘boxes’

6.3 Third reflection: climate modelling collection

6.4 Fourth reflection: meeting real climate modellers

6.5 Fifth reflection: reasons for modelling

6.6 Reflections overview – book summary: research and review

COLLECTED ENDNOTES

Chapter 1

Chapter 2

Chapter 3

Chapter 4

Chapter 5

Chapter 6

HINTS AND SOLUTIONS

Chapter 2

Chapter 3

Chapter 5

LIST OF ABBREVIATIONS

LIST OF SYMBOLS

General use

Specific use

BIBLIOGRAPHY

INDEX

This edition first published 2014. © 2014 by John Wiley & Sons, Ltd

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Library of Congress Cataloging-in-Publication Data

McGuffie, K.    The climate modelling primer / Kendal McGuffie, Department of Applied Physics, University of Technology, Sydney, NSW, Australia, Ann Henderson-Sellers, Department of Environment and Geography, Macquarie University, North Ryde, NSW, Australia. – Fourth edition.        pages cm    Includes bibliographical references and index.

    ISBN 978-1-119-94336-5 (cloth : alk. paper) – ISBN 978-1-119-94337-2 (pbk. : alk. paper) – ISBN 978-1-118-74684-4 (epdf) – ISBN 978-1-118-74707-0 – ISBN 978-1-118-74712-4 (cs) – ISBN 978-1-118-74718-6 (epub) – ISBN (invalid) 978-1-118-74719-3 (emobi) 1. Climatology–Mathematical models. I. Henderson-Sellers, A. II. Title.    QC981. M482 2014    551.601′1–dc23

2013030746

A catalogue record for this book is available from the British Library.

Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books.

Cover image: Ladders iStock File #13915338 © luchschen. Sky iStock File #99665 © Lumnicence. World iStock File #3112747 © janrysavy. Dice iStock File #9926268 © creisinger. All other images courtesy of the authors.

PREFACE

Today, climate modelling affects everyone, everywhere. Today, the Worldwide Web contains myriad resources for anyone interested in climate modelling. These include videoed talks by world experts, fantastic simulations made using some of the world’s most modern models and links that allow an interested beginner to actively participate in climate modelling themselves. This pervasive electronic environment means that our fourth edition of The Climate Modelling Primer is quite different from its predecessors. This latest edition still represents the culmination of more than a quarter of a century of learning about how to model climate but we have re-oriented the book towards engaging readers in an interactive experience, making use of internet resources such as scannable QR (quick response) codes and links to websites, articles, etc. Times change, and today’s climate model beginners more frequently wish to know how models work in order to allow them to understand model simulations properly, rather than themselves wanting to build, run or own a climate model. In response to this need, we suggest activities, such as developing a ‘treasure chest’ collection, writing blogs and addressing local community meetings that are designed to appeal to anyone wishing to develop their understanding of climate modelling science.

Climate modelling may seem to be about computers and technology but it is also very much about people. How models evolve and how well they are understood and who trusts their results depend critically on the scientists who build them, the funders who support them, the policy analysts who use them and the communicators who explain their outputs. This has always been true but today the emphasis has shifted from a scientific activity with little apparent public scrutiny to one about which everyone has an opinion. Many of these are less fully informed than they wish. The Climate Modelling Primer is dedicated to these people: readers who hope to gain understanding about 21st-century climate modelling.

Our Climate Modelling Primer (CMP) has greatly evolved since the first edition published in 1987. In keeping with the rapid development of climate models, modelling techniques and tools, the model environment, and indeed climate modellers themselves, every CMP version has changed. The first edition contained a ‘floppy’ disk that was, at the time, quite revolutionary. The second edition included a CD offering a small number of visualisations from actual climate model runs: a novel concept in 1997. The third edition also included a CD and we developed a dedicated website (www.climatemodellingprimer.net/). Now a classic, The Climate Modelling Primer can be considered as a guide to the rules and riddles of climate change science for those who need to know how models work and what they can deliver. Today, this audience includes virtually all thoughtful citizens and certainly all our political leaders.

This fourth edition aims to reach out by delivering information in a user-centred format. We take as our premise that each reader (each climate modelling student) intends to increase their understanding of climate models. Throughout the Primer we will examine climate modelling from the premise that ’all models are wrong; the practical question is how wrong do they have to be to not be useful’ (Box and Draper 1987). Naturally, climate prediction will be important but we will endeavour to draw attention to the other strengths and benefits of climate modelling throughout this text.

The book encourages learning by including a number of specific tools in every chapter:

A clear statement of learning objectives at the beginning of each chapter

Illustrative climate model understanding insets such as speed dating, model validation, feedback and so-called ‘wiring’ diagrams

Technical/mathematical boxes that explain underpinning theory more fully

Practical communication exercises about climate modelling as a ‘learn by doing’ enterprise

Downloadable, easy-to-use climate models to explore concepts

Biographies of people who are/have been important in climate modelling

Short exercises that summarise the chapter’s content and consolidate learning by means of research and review questions

A closing ‘Showcase Study’ that highlights some of the main points in the chapter

Below we demonstrate how these aspects will appear in this fourth edition of The Climate Modelling Primer.

Learning Objectives – for the whole book

After studying this book you will:

be familiar with the history of climate modelling and understand its aims for the future

understand how climate models are used in simulations of past, future and current climates at a variety of scales

be able to assess a wide range of communication forms employed to share results from climate model simulations with different audiences

recognise the variety of confidence and uncertainty measures associated with climate model outputs and know how to interpret them

appreciate the ways in which results from climate models affect 21st-century policy, laws, international trade and human development.

These items are reviewed as Learning Outcomes for this book in Chapter 6.

Illustrative climate model understanding boxes

These are exercises to be appreciated; indeed, we hope, enjoyed. We encourage you to dip into them.

Illustrative climate model understanding

Boiling a frog

There is a well-known story about what allegedly happens if you boil a frog. Take a quick look on the web to source a few examples of this such as cartoons, sketches, etc.; for example, boiling the frog movie: http://www.climatemodellingprimer.net/l/k001.htm

 There are two lessons to draw from this modern parable: the first emphasises the relationship between speed of change and response to it. The second exploits humorous comparisons between frogs and people to point out wisdom and awareness.

 In terms of climate modelling, the question is – which of these illustrations has value in explaining or demonstrating characteristics of models?

This might be the place to explain that we are referencing material differently in this edition. We offer a very short literature history at the end of each chapter – this is a background historical overview of the topics in that chapter. All our other literature citations are in the form of endnotes – gathered at the end of the book. These and other reference material are collected in a complete Bibliography, also at the end of the book.

Technical/mathematical boxes

These usually include mathematical developments that are worked outside the main text because they can be followed or not as the reader prefers. So you can skip these if you wish. For example:

Practical communication about climate modelling: learning by doing

Our hope in proposing an example ‘climate model communication’ idea in each chapter is to encourage sharing of modelling concepts and of climate model understanding. In all aspects of life, nothing better aids understanding than the process of trying to explain something to someone else. We have an undisguised second motive in making these suggestions – we hope that readers of our Primer will assist in widening community appreciation of all that climate models can do – and all they cannot!

A, B, C to R, S, T of climate modelling

At the end of most chapters, we invite reader review and involvement following the topics: R, Reasons for climate modelling; S, Signposts to understanding; and T, Treasures of climate model discovery and insight.

To encourage personal learning, we are employing an old technique that may be unexpected in this context: a collector’s chest. The goal is that as you read the Primer you collect climate modelling treasures: a small set of illustrations that you find persuasive, pretty and memorable. Beginning a great treasure collection will be the Climate Modelling Communication task in Chapter 1. One of the authors’ examples is mostly a collection of web links. When these occur in this edition, we also give QR code pictures: point your smartphone at the QR code here to view one of these simulations: http://www.climatemodellingprimer.net/l/k002.htm

Climate Model Communication Box 1

Write a blog (diary) or tweet: action

If you already have a blog or can ‘blog’ in a group site, that’s great. If not, either create one (this is simple) or write a personal diary. Or you may prefer to ‘tweet’.

 Your task is to create blog entries about 10 different aspects of climate models during the time it takes you to work through this book. Each entry has to be at least 100 words long and with a great headline. If you prefer to ‘tweet’, then create 50 tweets in total: five per topic.

 If you are unfamiliar with blogging or tweeting, the first step is not to write yourself but to hunt the web for blog entries that you like. Collect at least 10 entries you like, as different as possible (i.e. by different people; about different topics; written with different audiences in mind). List why you like each of these entries and try to develop a set of ‘good characteristics’ from this list that will help you to write interesting blogs yourself. Discuss your ideas with someone who is a successful blogger.

 Your goal is to influence others. Consider how you might try to measure this.

Downloadable, easy-to-use climate models to explore concepts

The downloadable models can be found on www.climatemodellingprimer.net. One is a simple energy balance model (EBM); another spreadsheet model illuminates anthropogenic climate change mitigation options. In Chapter 2, we explore the latter simple model, which calculates the required emission reduction rate (% per year) as a function of the desired climate target and the start date. In this figure, temperature limit goals are unachievable in the lower right, bright red area. Climate control ‘targets’ (resulting warming above preindustrial temperatures) rise exponentially as a function of start date (year) of any proposed reduction scheme. This is a screen snapshot from one of our spreadsheet models.

Biographies of people who are/have been important in climate modelling

Our ‘meet the modeller’ biography boxes are genuine introductions to real people. The first example we’ve chosen for this Preface may seem a little odd – our short biography is of Isaac Asimov (Biography Box 1). We chose Dr Asimov for a couple of reasons, as well as the fact that we both love his science fiction. Asimov has influenced people we mention in the Primer (read the biography to find out who). He also pushes science to close to its limits in his concept of psychohistory: a series of mathematical laws by means of which one can predict the future of civilisations. This idea is interesting today because we are now asking how far into unexpected and so far unexplored domains might climate models be useful: to predict human health, to construct policy about limits to population growth, or to frame political debate about geoengineering?

Biography Box 1

Meet the modeller: Isaac Asimov

Isaac Asimov (2 January 1920 – 6 April 1992) was an American scientist, famous author and professor of biochemistry at Boston University. A prolific writer, he is renowned for the fact that he published books in all 10 major categories of the Dewey Decimal (library) System. He is credited by the Oxford English Dictionary with the introduction of the words robotics, positronic (his robotic brains were positronic) and psychohistory (the theory of large numbers of intelligent agents invented by Hari Seldon as the basis of the Foundation series).

 Isaac Asimov described Carl Sagan as one of only two people he ever met whose intellect surpassed his own. The other, he claimed, was the computer scientist and artificial intelligence expert Marvin Minsky. Paul Krugman, a Nobel Laureate in Economics, has stated that it was Asimov’s concept of psychohistory that inspired him to become an economist (Krugman 2010).

Read more

Asimov, I. (1980) In Joy Still Felt: The Autobiography of Isaac Asimov, 1954–1978. New York: Doubleday/Avon. pp. 217, 302.

Asimov, I. (1988) Prelude to Foundation. New York: Bantam Books.

Watch

Asimov on life-long learning: http://www.climatemodellingprimer.net/l/k003.htm

Biography Box 2

Meet a modeller: Ann Henderson-Sellers and Kendal McGuffie

Climate modelling leadership: AH-S conducted the world’s first climate model simulation of tropical deforestation in 1982, which led to the quantification of the role of forests in large-scale climate change. KMcG and AH-S worked together in the late 1980s/early 1990s to deliver one of the first digital intercomparisons of climate model results through the Model Evaluation Consortium for Climate Assessment (MECCA) Analysis Team (see 2nd edition of the CMP’s CD for these results).

Popular recognition: This is their seventh joint book if you include the one they co-wrote about hiking the Australian Great North Walk – a history of the 250 km bush track connecting the New South Wales cities of Newcastle and Sydney.

Kendal McGuffie and Ann Henderson-Sellers. Photo source: K. McGuffie and A. Henderson-Sellers.

Climate modelling connectivity: Ann owes much of her understanding of climate models to Jim Hansen and of the land surface to Bob Dickinson. Both Kendal and Ann have worked closely with Greg Holland, the respected mesoscale modeller, including in the co-authorship of the definitive paper published in 1998 in the Bulletin of the American Meteorological Society.

Life and times: Kendal McGuffie is an Associate Professor and Head of the School of Physics and Advanced Materials at the University of Technology, Sydney. He graduated from the University of Edinburgh with a BSc in Physics and went on to complete a PhD at the University of Liverpool on cloud and radiation interactions. His first paper resulted from what his supervisor considered to be an excessive fascination with the hysteresis cycle of snow albedo. He has also researched tracking the hydrological cycle using stable water isotopes and conducted observational studies of tropical convection in association with the development of novel observational platforms for tropical cyclone monitoring.

 Ann Henderson-Sellers was one of the founders of model-based analysis of the land surface in climate, contributing fundamentally to understanding anthropogenic climate change. Thirty years ago, she co-created (with Mo Wilson) the first digital dataset of vegetation and soil and, in 1992, she designed and co-ordinated the first international intercomparison of climate modules. She has held many positions, including being the Director of the United Nation’s World Climate Research Programme culminating in its contributions to the IPCC being recognised in the Nobel Peace Prize for 2007.

 Together these researchers have contributed to a wide variety of aspects of climate: explaining models, evaluating simulations and rescuing data; for example, between 1985 and 1995 they jointly identified and accessed archival sources that showed cloudiness increasing over the 20th century. They also share random godchildren, an electric car, pleasure in movie going, a penguin and a chocolate Raisin.

Read more

Henderson-Sellers, A., Zhang, H., Berz, G., et al. (1998) Tropical cyclones and global climate change: a post-IPCC assessment. Bull Am Meteorol Soc 79(1), 19–38.

Henderson-Sellers, A., McGuffie, K. (eds) (2012) The Future of the World’s Climate. Amsterdam: Elsevier Scientific. (Winner of the Atmospheric Science Librarians International (ASLI) Choice Award for 2012.)

Watch

Communicating climate change: hurricane hazards’ honesty (KMcG and AH-S), 2011, Rhodes:http://www.climatemodellingprimer.net/l/k004.htm

Our second reason for including biographies of well-known climate modellers, beyond the obvious one of introduction, is to try to mention some of the personal connections among folks in this field. Although there are many modellers today, this community grew quite fast from a tiny origin. Tracing some modeller links illuminates how some models seem more closely related than others. For anyone interested in family histories, there are fascinating tales to unravel of relationships, break-ups and long-lost siblings.

Speaking of links, it is time to introduce ourselves (Biography Box 2).

As another example of the QR codes we will use throughout the Primer, here is a link to a talk by one of our most beloved modellers – check him out. http://www.climatemodellingprimer.net/l/k005.htm

1 Summary: research and review

Review topic and question

Write a 200-word description of any climate model or climate model simulation you know about that is suitable for a public blog or a newspaper column. For example, model predictions of future climate changes relevant to where you live.

Discussion topic

Assess the success of either your communication (in your response to the above invitation) or our description of what will be found in this book. Did the communication mostly focus on how models work, on the confidence or uncertainties of predictions, on the development that underpins models or on the actions that are demanded by the results of the simulation?

 Rate the success of either communication on a scale of 1 (dreadful) to 10 (fully successful).

Chapter summary

At the end of every chapter we offer a two-part set of exercises: the first part is questions that can be answered – say in a report or essay. The second part contains more open-ended questions to prompt discussion. This is also the very last section of the book – reviewing and reflecting on learning gained from the book as a whole.

All these collected summary topics can be pursued by an individual or as part of class or group learning.

Chapter closing showcase

Here we list the boxes that appear in the six chapters of The Climate Modelling Primer and give a hint about the topics they illustrate. As well as the biography boxes and the technical (mathematical) material boxes, there are eight sets of explanatory boxes that involve the reader in thought, further study or research.

1. Speed Dating: Meet a Model – a very quick ‘meet and greet’ of a real model

2. CSI (climate simulation intrigues) in sets of four per chapter

3. Model Validation – comparing observations and model results

4. Spotlight on Climate Models – probing one aspect of important climate modelling papers

5. Climate Model Communication – ideas to tempt climate model sharing

6. Feedback diagrams – connecting components

7. Wiring the World – describing relationships

8. Showcases – climate model paper highlight at the end of each chapter

Table 1 Boxes in the book. The boxed material in Chapters 1–5 (and also in Chapter 6, but not boxed) can be checked and cross-referenced using this summary

Throughout the book, these boxes offer reviews and forward glimpses (Table 1).

There are a number of ‘routes’ through this book. We hope you will begin with Chapter 1 but, beware, it contains lots of ideas and material, much of which is explained in subsequent chapters. If you come across stuff you don’t fully follow, don’t worry too much just there. For example, if you need to find out about the skill and capability of today’s models, go to Chapter 5 but we also recommend reading Chapter 1 on ‘why model’. If you want to try modelling for yourself then read Chapter 3 with a preliminary scan of Chapter 2 on the evolutionary history of climate modelling and download the simple models described. Chapter 4 is rather mathematical but if you really need to know the ingredients of modelling, then it is your study text, after an introduction in Chapter 1 or 2.

Finally, we still enjoy learning about climate models and their applications and we do very much hope that our readers will share some of our enjoyment in this new, fourth edition of The Climate Modelling Primer.

Kendal McGuffie and Ann Henderson-SellersSydney

ACKNOWLEDGEMENTS

We are, as ever, immensely grateful to Brian who seems always ready and willing to set aside his own research and book writing in order to help us with ours. Without him we would have poor spelling, terrible punctuation and a whole lot of muddled science – thanks for everything Bri!

We also wish to thank all our reader-reviewers of this edition. Drs Liam Phelan and Huqiang Zhang were especially helpful in their comments, criticisms, edits and enthusiastic support. We are also grateful to (in alphabetical order): Dr Jean-François Exbrayat, Dr Supriya Mathew, Dr Debasish PaiMazumder, Martin Rice, Dr Maria Tsukernik, and Martin Vezér. They all made very useful contributions to the editing phase. This edition could have included mistakes from earlier editions if it were not for the diligent feedback received from many earlier readers, many of whom joined us in the Model Evaluation Consortium for Climate Assessment Analysis Team (pictured below) – thank you all.

Despite these acknowledgements, we must, of course, assume full responsibility for any remaining imperfect explanations and for any errors that may have crept in. Please contact us via the web page (http://www.climatemodellingprimer.net) and let us know if you find any of these.

We have drawn on a very wide variety of published material. Specific credits are given where the figure, table or quotation is used, coupled with all references being listed in full in the Bibliography at the end of the book. Fiona Katauskas (fionakatauskas.com) drew most of the cartoons. ‘Why cutting down forests reduces rainfall’ is reproduced by permission of Cathy Wilcox, Fairfax Media.

ABOUT THE COMPANION WEBSITE

This book is accompanied by a companion website:

 

www.wiley.com/go/mcguffie/climatemodellingprimer

 

The website includes:

Figures from the bookTables from the book

The authors also operate a website:

 

www.climatemodellingprimer.net

 

It is frequently updated and contains:

All the hot-linked QR code addressesUpdates and corrections to this and earlier editionsAll the downloadable computer modelsReaders’ feedback

Vocabulary of Climate

Plate 1.1 Vocabulary of climate. How we discuss climate today is illustrated in this ‘wordle’,1 created by Neville Nicholls using the text in Chapter 3 of the 2012 Intergovernmental Panel on Climate Change (IPCC) Report on Climate Extremes.2 Most of the work drawn upon is collaborative, so the phrase ‘et al.’ indicating with others dominates. Interestingly, precipitation is more frequently used (larger) than temperature; projected and projections occur much more often than evidence; and, relevant for this book, models and confidence are both fairly important.

Plate 1.2 Eclipse 2012 – the climate is driven first and foremost by solar radiation

1

Why Model Climate?

‘All models are wrong, but some are useful.’ (Box and Draper 1987, p4)

‘The strongest arguments prove nothing so long as the conclusions are not verified by experience. Experimental science is the queen of sciences and the goal of all speculation.’ (Roger Bacon ca. 1214–1294)

LEARNING OBJECTIVES

After completing this chapter, you will be able to:

recognise the many reasons for having models

track the history of climate theory becoming fact

list the factors affecting planetary scale climate

explain the concept of climate feedback and give examples

recognise the mechanisms whereby persistent and widespread life affects climate.

1.1 Introduction

This book is entitled The Climate Modelling Primer, a title that presupposes modelling to be a useful exercise, and that readers are familiar with the idea of models and the reasons for participating in modelling. We assume you are interested in building or testing models or in exploiting their results. This foundation chapter tests these assumptions by examining the important question, ‘Why model climate?’. We try to answer this question in three ways: first by looking at reasons for modelling in general; by applying a selection of these reasons to climate modelling; and then by taking a very different view of Earth’s climate, from a distant galaxy, and using this metaphorical alien climate scoping to investigate some of the fundamental ingredients of planetary climates and thus of climate models. In this opening chapter we cover a wide variety of topics quite quickly to give a sense of the wonderful breadth of climate models and their achievements. In doing this we do not define or explain in much detail because these explanations constitute the rest of this book. If you come across a concept you wish to understand better, you can locate a further description of it using the index or checking the summary of boxed material at the end of the Preface.

The characteristics of climate and hence those that climate models must try to reproduce can be thought of as a primer – or perhaps an A, B, C – as outlined in Table 1.1.

A is for astronomy

: any planet or moon with a climate is constrained by fundamental astrophysical conditions.

B is for boundary and for biology

: climate becomes interesting to model most often when it relates to living systems and where it touches boundaries.

C is for comprehension

: the reasons for constructing, operating and analysing climate models are ultimately to try to understand climate change and variability.

To encourage personal learning, we are employing an old technique that may be unexpected in this context. It is a ‘collector’s chest’. In the 18th and 19th centuries, such collector’s chests were built to hold and attractively display novel collections of scientific specimens. Many voyages of discovery included natural scientists who would have carried their rare and curious samples home in such sturdy wooden chests. Our example (Figure 1.1), the Macquarie collector’s chest, was almost certainly intended as a special presentation piece to celebrate the colony of New South Wales once the Governor, to whom it was given, arrived back in the UK. If you are not keen on stuffed birds and old seaweed, another type of treasure collection still to be found in some homes is the heritage quilt, and a still more modern version is scrapbooking.

Table 1.1 A primer, or ‘A, B, C’, of climate modelling

A, B, C

Aspects of climate modelling

A: Astronomy

Astrophysical attributes – orbit, atmosphere, radiative budget, existence/prevalence of water …

B: Biology and boundaries

Life and climate, surface conditions, volcanic activity …

C: Comprehension

Prediction, testing theories, raising questions, bracketing outcomes, directing data collection, disciplining policy …

Figure 1.1 The Macquarie collector’s chest. Collections like these were for display and specifically designed as attractive and persuasive depictions of unusual places.