Paleoclimate

Synopsis

Earth's climate has undergone dramatic changes over the geologic timescale. At one extreme, Earth has been glaciated from the poles to the equator for periods that may have lasted millions of years. At another, temperatures were once so warm that the Canadian Arctic was heavily forested and large dinosaurs lived on Antarctica. Paleoclimatology is the study of such changes and their causes. Studying Earth's long-term climate history gives scientists vital clues about anthropogenic global warming and how climate is affected by human endeavor.


In this book, Michael Bender, an internationally recognized authority on paleoclimate, provides a concise, comprehensive, and sophisticated introduction to the subject. After briefly describing the major periods in Earth history to provide geologic context, he discusses controls on climate and how the record of past climate is determined. The heart of the book then proceeds chronologically, introducing the history of climate changes over millions of years--its patterns and major transitions, and why average global temperature has varied so much. The book ends with a discussion of the Holocene (the past 10,000 years) and by putting manmade climate change in the context of paleoclimate.


The most up-to-date overview on the subject, Paleoclimate provides an ideal introduction to undergraduates, nonspecialist scientists, and general readers with a scientific background.

Summary

Chapter 1: Introduction to Paleoclimatology

Paleoclimatology studies past climates to understand present and future climate change. This chapter provides an overview of the field, including its history, methods, and data sources.

Real-world example:
Ice cores from Antarctica contain trapped air that can be analyzed to reconstruct past atmospheric CO2 levels and temperatures.

Chapter 2: The Earth's Climate System

The Earth's climate system is a complex interplay of components, including the atmosphere, ocean, and land surface. This chapter examines the processes that regulate climate and how they have changed over time.

Real-world example:
Satellite data shows that the Arctic sea ice is melting rapidly, which is a consequence of rising global temperatures.

Chapter 3: Climate Proxies

Paleoclimatologists use a variety of proxies to reconstruct past climates. These proxies include tree rings, ice cores, and lake sediments. This chapter discusses the strengths and weaknesses of different proxies.

Real-world example:
Tree rings can be used to reconstruct past temperatures and precipitation by analyzing the width and density of the rings.

Chapter 4: Climate Change Over Earth's History

This chapter presents a timeline of major climate changes that have occurred throughout Earth's history. It includes periods of extreme warmth, glacial periods, and abrupt climate transitions.

Real-world example:
The Permian-Triassic extinction event, which occurred 252 million years ago, was the most severe extinction event in Earth's history and was likely caused by global warming.

Chapter 5: The Last Glacial Period

The Last Glacial Period, which occurred from about 110,000 to 10,000 years ago, was a time of significant climate change. This chapter examines the causes and consequences of this period, including the growth and retreat of ice sheets.

Real-world example:
Evidence from ice cores indicates that temperatures during the Last Glacial Period were much colder than today, with ice sheets covering North America and Europe.

Chapter 6: The Holocene

The Holocene is the current geological epoch, which began about 10,000 years ago. This chapter discusses the climate changes that have occurred during the Holocene, including the rise in sea level and the Medieval Warm Period.

Real-world example:
Historical records show that the Medieval Warm Period, which occurred from about 800 to 1300 CE, was a time of relatively warm temperatures in Europe.

Chapter 7: Human Impacts on Climate

Human activities have significantly impacted Earth's climate in recent centuries. This chapter examines the role of greenhouse gases, deforestation, and land use changes in climate change.

Real-world example:
The burning of fossil fuels has released large amounts of CO2 into the atmosphere, contributing to global warming.

Chapter 8: Future Climate Change

This chapter presents projections of future climate change based on models and paleoclimate data. It discusses the potential impacts of climate change and the mitigation and adaptation strategies that can be implemented.

Real-world example:
Models predict that global temperatures could rise by several degrees Celsius by the end of this century, which could lead to extreme weather events, rising sea levels, and other impacts.