alt="Remember"/> We want you to remember everything you read in this book, but if you can’t quite do that, then remember the important points flagged with this icon.
Beyond the Book
In addition to the ocean of information and insight we provide in this book, you have access to even more help and information online at Dummies.com, including a Cheat Sheet that serves as a quick reference guide to this book. We also posted a list of our ten favorite sea creatures — a bonus item that truly goes “beyond the book.” To access the Cheat Sheet, go to www.dummies.com and search for “Oceans For Dummies Cheat Sheet.”
Where to Go from Here
You’re certainly welcome to read this book from cover to cover, but we wrote it in a way that facilitates skipping around. For a quick cruise around the ocean, turn to Chapter 1. To find out how the ocean formed and how marine life evolved (how the ocean as we know it came to be), head to Chapter 3. To scope out different areas of the ocean, head to Part 2, where we divide the ocean into zones and ecosystems and check out the seafloor.
All chapters in Part 3 are required reading, but feel free to just flip through them at your leisure to look at all the pretty pictures. Words just can’t capture the beauty of the ocean and the creatures that call it home as well as photos can. Chapter 21 is also required reading. One of the primary reasons we wrote this book is to recruit you to join our mission to save the ocean — one of the world’s most precious resources. In Chapter 24, we provide a menu of easy ways you can help.
Other than that, you’re pretty much on your own to explore at your own pace and as your curiosity leads you. Enjoy!
Part 1
Getting Started with Your Ocean Voyage
IN THIS PART …
Take a quick primer on ocean fundamentals — from dividing the ocean into oceans (plural) and getting up to speed on the water cycle to engaging in a quick meet-and-greet with the ocean’s inhabitants.
Take inventory of the various ways the ocean contributes to our health and happiness, not to mention our very existence.
Discover how the ocean and oceans formed and how life on Earth may have begun.
Trace the evolution of marine life from the Paleozoic to the Cenozoic era and everything in between.
Look ahead to find out what the future of the ocean might look like.
Chapter 1
Brushing Up on Ocean Fundamentals
IN THIS CHAPTER
Before you dive into any large or complex topic, you’re wise to step back and look at the big picture. A general understanding provides a framework on which to hang the details. In this chapter, we provide that framework, establishing a context for understanding the many facets of the ocean and how they all fit together.
We start by introducing you to the ocean and breaking it down into its five “oceans.” Then, we get into a few topics in the realm of physical oceanography — the water cycle, the shapes of the ocean basins, meteorology, and other properties and processes that explain what makes the ocean tick from a physical standpoint. We then introduce you to the various groups of life-forms that populate the ocean — plants, animals, and beings that fit in neither (or both) categories. Finally, we wrap things up with a discussion of the ocean’s current state and the human-ocean relationship — the benefits we gain from the ocean and our responsibilities as environmental stewards in protecting and preserving it.
Get ready for a wild ride. In this chapter, we cover a lot of ground, not to mention all that water!
Taking a Nickel Tour of the Ocean(s)
The ocean is big. How big? Well, it covers about 360 million square kilometers (140 million square miles), which is just a smidgen more than 70 percent of Earth’s surface. Volume-wise it contains approximately 1.3 billion cubic kilometers (321 million cubic miles) of water — that translates to about 352 quintillion gallons, which accounts for about 97 percent of Earth’s water. In terms of living space, the ocean comprises about 99 percent of the biosphere — all land, water, and atmosphere where life on Earth exists.
Because it’s so big, people have developed all sorts of ways to slice and dice it to better understand and describe the different areas that make it up.
Dividing the ocean into oceans … or not
Earth has only one ocean, which is why we will refer to it as the ocean (singular) throughout this book. Geographically, it’s divided into four or five oceans, depending on who’s doing the dividing. Prior to the year 2000, text books recognized four oceans: the Atlantic, Pacific, Indian, and Arctic. Sometime around the year 2000, the International Hydrographic Organization designated a fifth ocean the Southern Ocean — a band that wraps around the world from the coast of Antarctica to 60 degrees south latitude (see Figure 1-1). Here’s a brief description of each of the five oceans, in order of size, because, well, size matters.
