O C E A N S

Oceans - contain most of the Earth's water.

Today we rely on the oceans for an array of resources and pure enjoyment.

Until now, the oceans were the perfect home for marine life and a poor source of water for humans. Salt water couldn't cure thirst and it caused rust.

Fig. Fagatale Bay National Marine Sanctuary, island of Tutuila, American Samoa. Photo by Kip Evans.

But now that other reservoirs of water are running low, people are reconsidering the ocean as a source of drinking water. If developing desalination technologies succeed, the oceans may provide us with more than "a drop to drink".

We rely on the oceans for food and other natural resources. Very few of us hunt and capture wild game, but many of us have a taste for wild tuna sandwiches.

Mariculture is also important - bringing farm-raised foods such as salmon and shrimp to local groceries at bargain prices.

We consume most of the catch in less visible ways, in feed used for agriculture and numerous chemical products including biomedicines. Whether by capture or culture, we consume many living resources from within the ocean reservoir. The quality and quantity of these living ocean resources depends how well we manage these resources and their environment.

Fig. Frozen tuna for sashimi, Tokyo Fish Market, Japan. Photo by Memorie Yasuda.

The ocean brings us comfort. Although sea air can bring the discomfort of high humidity, it also moderates regional weather, preventing scorching summers and snowy winters. Combined with irresistably good looks and other charms, coastal properties are in demand for recreation, living, farming, and wildlife.

Life has always depended on the sea. The moderate environment of the oceans harbored early life when terrestrial environments were still too harsh.

Fig. Fossil fish from the Cretaceous Niobrara Formation, Kansas. Photographer Kenneth Jenkins, image used with permission.

Even well after the start of life, special living things were made possible by the presence of shallow seas. Dinosaurs flourished in shallow seas that covered many continents during the Mesozoic. Beach property existed in states like Colorado and Wyoming. Abundant marine and coastal fossils serve as reminders in areas that are now land.

The water in the oceans is the reason life can exist on Earth and life is still drawn to it.

© Copyright 2002 by the UC Regents and the Wyland Foundation.
All rights reserved

PART 1
Water on Earth
 • Overview
 • Stores of Water
 • Infinite cycle:
   finite resource
 • Sculpting the earth
 • What's left to drink?
Quiz
Glossary
Resources
Teacher's guide
Information Sources

•  Activity Oceans.1
Investigate: Is desalination under consideration in your community?

Starting Points:
Desalting plant for some county water proposed for Carlsbad
San Diego Union Tribune

Seawater desalination in California
California Costal Commission

•  Activity Oceans.2
Investigate: What is harvested from the ocean? Consider what's captured and cultured.

Starting Points:
Recent trends in Global Fishery Production
Global statistics on captures and cultures.
Food and Agriculture Organization, United Nations

•  Activity Oceans.3
Investigate: Have ancient oceans existed where you live today?