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Book Introduction to the Second Edition for Students and Instructors

Dear Students and Instructors,

We are excited to provide you with the opportunity to learn about Earth's climate of the past, and its relevance to climate of the present and future, through an inquiry‐based curricula design. This is the second edition of Reconstructing Earth's Climate History – Inquiry‐Based Exercises for Lab and Class, and we have worked hard to maintain the best content of the first edition, while also expanding topics, updating exercises, and reorganizing content to scaffold data‐rich material and support your learning. As the title of the book implies, this is a book that has you, the student, playing an important active role; you are to make observations, ask questions, wrestle with uncertainly, interact with your classmates and instructor, and work to synthesize information, pose evidence‐based hypotheses, and infer broad implications from case study examples. All of this is part of the process of scientific inquiry, which aims to build your content knowledge and observational and analytical skills.

In order to get the most out of your work with this book, we want you to know why and how we designed it, as well as what is new to the second edition. We think understanding the design will give you a roadmap of what to expect as you use this book to reconstruct Earth's climate history.

Motivation and Purpose

There has never been a more critical time for students to understand how the Earth works. Understanding the causes and potential consequences of Earth's changing climate are of particular importance because modern climate change is an issue that impacts economies, societies, environments, and lifestyles; furthermore these impacts are distributed differently across countries and populations. The context for understanding global warming today lies in the records of Earth's past. This is demonstrated by decades of paleoclimate research by scientists in organizations such as the International Ocean Discovery Program, the Antarctic Geological Drilling Program, the Byrd Polar and Climate Research Center's Ice Core Laboratory, and many others. The purpose of this book is to put key data and published case studies of past climate change at your fingertips, so that you can experience the nature of paleoclimate research and discovery. You will evaluate data, practice developing and testing hypotheses, and infer the broader implications of scientific results. It is our philosophy that addressing how we know is as important as addressing what we know about past climate.

Use of Real Data

The chapters in the book can be considered multipart exercises that build upon authentic data from peer‐reviewed scientific publications. One of the most effective means of conveying science data is through figures – graphs, photos, diagrams. Therefore, unlike many books where the figures supplement the text, in this book the figures are the central elements of every exercise. Questions and tasks within each exercise are constructed around the data or concepts presented in figures. This means that it is essential to carefully examine the figures and diligently read their captions. This may not be easy at first, but with practice (and this book will give you lots of it!) it will become second nature.

Content Topics

The content topics chosen for this book support the Essential Principles of Climate Science (USGCRP, 2009; Table 1)1. The relevance of investigating past climates for understanding modern climate change and for predicting future climate change is evident throughout the book. Reconstructing past climate change relies on investigations of multiple archives, including tree rings, corals, speleothems, ice, sediment, and sedimentary rock. In this book we focus primarily on climate change during the Cenozoic Era (the last 66.0 million years of Earth’s history; see timescale inside front cover of book). We therefore draw largely from ocean sediment core and ice core records, which are valuable archives of the past 200 million years and past 500 thousand years, respectively. The second edition expands on this to include more terrestrial records as well. As you will see, obtaining detailed natural records of Earth's climate history is a challenging undertaking, often involving expeditions to remote locations, complex coring technology, careful planning and execution, and hard work. Once obtained, paleoclimate records must be systematically described, ages must be determined, and indirect evidence (i.e. proxies) of past climate must be analyzed. Much like the work of a detective, geoscientists and paleoclimatologists reconstruct what happened in the past, and when and how it happened based on the clues left behind by the events that took place.

TABLE 1. Chapter alignment to scientific content, skills, and USGCRP (2009) climate literacy principles.

The chapters in this book are organized to first explore fundamental aspects of paleoclimate research and the “tools” used to conduct this research. Chapter 1 introduces how marine and terrestrial records are obtained, with increased representation of terrestrial records compared to the first edition. Chapter 2 focuses on describing marine sediments, a major archive of past climate. Chapters 3–5 focus on how ages of geologic and paleoclimate records are determined using multiple methods. New to the second edition, Chapter 3 introduces relative and radiometric age dating techniques. We also reversed the order of two chapters from the first edition: paleomagnetism (now Chapter 4) and biostratigraphy (now Chapter 5) because magnetostratigraphy is a bridge between the numerical ages that radiometric dating provides and the relative ages that fossils provide. Chapter 5 was expanded to include a new unit on organic‐walled microfossils.

Chapters 6 and 7 transition the content of the book from paleoclimate tools (specifically, proxies) to chronological case studies. Chapter 6 provides an overview of the Phanerozoic CO₂ record and introduces stable carbon isotopes, whereas Chapter 7 provides an overview of Cenozoic climate history based on oxygen isotope data in fossils and ice. The next five chapters of the book continue chronological case studies that open windows to examine the causes and consequences of climate change patterns and events within the Cenozoic: including climate cycles (Chapter 8, which now also includes access to a downloadable spreadsheet of a climate cycle case study), the Paleocene–Eocene Thermal Maximum (Chapter 9), the onset of Antarctic glaciation (Chapter 10), Antarctica and Neogene climate change (Chapter 11, which is a condensed version of two chapters in the first edition), and Pliocene warmth (Chapter 12, with expanded sections on sea level change and the transition to Pleistocene Northern Hemisphere glaciation). The final two chapters are new to the second edition. Chapter 13 explores connections between climate change and life with examples from the Paleozoic, Mesozoic, and Cenozoic Eras. Chapter 14 examines connections between climate change and human civilizations with examples from water‐stressed regions in modern and historical times. A more detailed description of each chapter is provided in the Table of Contents.

Transportable Skills

In addition to introducing and working with paleoclimate content, the exercises in this book are also designed to provide opportunities to develop and practice scientific and other life skills (Table 1). These include making observations, formulating hypotheses, practicing quantitative and problem‐solving skills, making data‐based interpretations, recognizing and dealing with uncertainty, working in groups, communicating (written and oral) with others, synthesizing data, and articulating evidence‐based arguments. Many of these scientific skills are also valued by other disciplines – from business to the social sciences. Therefore, whether your aspirations are to pursue a career in science or in another field, working with the data in this book in this inquiry‐based way will help you develop valuable, transportable skill sets.

Practical Use of Multipart Exercises

Each chapter in this book is a multipart exercise. The first part of each chapter is typically designed to introduce a topic and/or gauge prior knowledge, and therefore to identify possible misconceptions. In‐depth exploration of the topic follows in subsequent exercise parts, as does the synthesis of the important implications of the data. How you use these exercises will depend on the focus of your course, time, prior knowledge (both instructor and student), and class size. Therefore you may explore a chapter from beginning to end, or you may be extracting specific parts of exercises that support your curriculum and instructional goals, and course management decisions. Some exercises may be assigned as homework, and others may serve as in‐class activities that can be jumping‐off points for lectures, or an entire chapter may serve as a weekly lab activity. In all cases, the value of group discussion at different junctures within, and/or at the end of, an exercise cannot be underestimated. As undergraduate instructors, the authors of this book all practice a “do‐talk‐do” approach to teaching and learning, whereby we integrate both inquiry‐based student learning and lecture in our classes. We encourage instructors using this book to do the same. For instructors to successfully adapt inquiry‐based approaches (as used in this book), it almost certainly is necessary to cover less material than would be covered in a semester (or quarter) of lecture‐only classes. This is because inquiry takes more time than does lecture. However, the benefits of having students take active roles in the construction of their knowledge and the development of transportable skills are well worth this trade‐off. We recognize that instructors using this book are not necessarily experts themselves in paleoclimatology. Therefore, we developed comprehensive instructor guides for each chapter to provide essential background information, detailed answer keys, and alternative implementation strategies, as well as to provide links to other supplementary materials and examples for assessment.

Audience

Because of the flexible design of these multipart exercises, they can be (and have been) used at multiple levels and with multiple audiences. Collectively the use of all of the exercises in this book would support an undergraduate course in paleoclimatology, global climate change, or paleoceanography. The select use of specific chapters or parts of chapters can also support topics in many Earth science courses (e.g. historical geology, oceanography, stratigraphy, Quaternary science).

Classroom Tested

The flexible and effective use of these exercises with multiple audiences at multiple levels is demonstrated by our classroom testing; we have used exercises from this book in our introductory geoscience courses for nonmajors, advanced courses for geoscience majors, and even in workshops for K‐12 teachers, for PhD students (e.g. Urbino Summer School on Paleoclimatology), and for undergraduate instructors. Our classroom and lab experiences, and the feedback from students and workshop participants informed the design and revisions of the exercises and the content included in the instructor guides.

In using this inquiry‐based book we hope you gain new knowledge, new skills, and greater confidence in making sense of the causes and consequences of climate change. Enjoy the challenge and the reward of working with scientific data and results!

Kristen St. John, Mark Leckie, Kate Pound, Megan Jones, and Larry Krissek

April 2021