also assume, however, that you know climate change exists, that you recognize humans contribute to this problem, and that you want to understand why global warming is happening.
Icons Used in This Book
Throughout this book, you see little icons sprinkled in the left margin. These handy symbols flag content that’s of particular interest.
Beyond This Book
This book is full of information in plain English about climate change. If you want some additional pieces that you can refer to on a regular basis, check out the book’s Cheat Sheet at www.dummies.com. Just search for “Climate Change For Dummies Cheat Sheet.”
Where to Go from Here
This book like all other Dummies books is linear, meaning you can read any chapter or section that interest you. If you already know something about the subject or want to find out more about a specific topic, you can open any chapter and start reading. You also can scan the Table of Contents or the index, find a topic that piques your interest, and turn to that chapter to begin reading.
If you’re entirely new to the subject of climate change, you’ll likely want to read this book the old-fashioned way, starting at the beginning and working through to the end. Or, if you’re interested in reading about potential solutions, head to Part 5. No matter where you start, you can find out about causes, effects, progress, and probable solutions.
Part 1
Understanding Climate Change
IN THIS PART …
Explore the science behind the climate emergency: what are the causes, what are the effects, what can humans do about it?
Understand what greenhouse gases are, why they’re vital for life on Earth, and how they’re heating up the atmosphere.
Investigate why scientists are certain that greenhouse gases are the cause of the global warming that the Earth is experiencing today.
Look at some of the other factors contributing to climate change.
Chapter 1
Covering the Basics of Climate Change
IN THIS CHAPTER
The phrase “global warming” has been in the news since the late 1980s, but climate change, as global warming is also known, has been around much longer. In fact, it has been a constant throughout history. Earth’s climate today is very different from what it was 2 million years ago, let alone 10,000 years ago. Since the beginnings of the most primitive life forms, this planet has seen many different climates, from the hot, dry Jurassic period of the dinosaurs to the bleak, frozen landscapes of the ice ages.
Today, however, the planet is experiencing something new: Its climate is experiencing rapid and dangerous changes. Scientists are certain that these changes have been caused by emissions produced by human activities. By examining previous changes in the Earth’s climate, using computer models, and measuring current changes in atmospheric chemistry, they can estimate what global warming might mean for the planet, and their projections are scary.
Fortunately, Earth isn’t locked into the worst-case-scenario fate yet. By banding together, people can put the brakes on global warming. In 2009, when this book was first released, we had more time to apply the brakes than now. This chapter explains the essentials of global warming and what everyone can do to achieve a greener future.
Getting a Basic Overview — Global Warming 101
When “global warming” became a household phrase, greenhouse gases (GHGs), which trap heat in the Earth’s atmosphere, got a bad reputation. After all, those gases are to blame for heating up the planet. But, as we discuss in Chapter 2, GHGs in reasonable quantities aren’t villains, they’re heroes. They capture the sun’s warmth and keep it around so that life as it’s known is possible on Earth. The problem starts when the atmosphere contains too great an amount of GHGs. (In Chapter 3, we look at how scientists have determined the correlation between carbon dioxide in the atmosphere and temperature.)
Other factors, which we discuss briefly in the following sections, affect the Earth’s climate. Some are short-term — mostly those are seen as variations in weather, like El Niño or El Niña. The ones that matter most, though, are those that have long-term effects on climate. When the overall temperature of the Earth and the oceans rise, that’s not just a change in the weather. And it’s not just a normal variation that might have been observed in the past. That’s a change in the Earth’s climate.
