There is no other planet like Earth in our solar system: no other planet is both rocky and has flowing water at its surface. Without water, life as we know it could not exist. Although our planet is covered by seemingly vast oceans, only a small fraction of the water on Earth is fresh, and even less is readily accessible. As the population grows, it becomes more important to understand how to manage and protect our fresh water supply.

Water is very useful. It generates electricity and waters the grains, fruits and vegetables that people and animals eat. It can also be very dangerous, causing much destruction from flooding and landslides. Concern about the purity of both surface and groundwater is a growing issue. If we misuse chemicals on our crops, lawns, or industry both surface and groundwater supplies may be contaminated.

Some scientists study water in streams, rivers, and underground. They measure rain and snowfall, how much runs off into streams, [taking soil and water samples]and how much filters through the soil and rocks into the underground water system. These scientists work with biologists, chemists, public health specialists, physicists, geologists and atmospheric scientists, who also have a personal and professional concern about water. What do we call these scientists? Hydrologists

Did you know? The Antarctic ice sheet is up to 3 miles thick.

Some scientists study oceans. They investigate how biology, geology, meteorology, physics, and chemistry interact to shape the marine environment. They have discovered that the floor of Earth’s oceans has high mountains, deep valleys, shelves and slopes, and is as varied as the surface of the land. Some of these scientists study how tides and storms move sand to and from beaches. Because a large percentage of Earth’s population lives within 50 miles of a coast, understanding these processes is very important. They also investigate how the oceans move heat around our planet, and they work with meteorologists to predict changes in weather and climate. This team is now better able to predict and monitor El Niño and La Niña events, which are warm and cold ocean currents that have a big impact on weather. Ocean Submersible

Did you know? Water covers 71% of the Earth.

Many scientists concentrate their attention on the chemical composition of ocean water. Most of the substances in seawater come from the land, where they have been dissolved and then carried by rivers to the oceans. Some of these substances are pesticides, herbicides, and other waste products from human activities. These scientists work with marine biologists to understand the impact that toxic chemicals are having on marine plants and animals. They use ships, deep submersibles, fixed platforms, underwater laboratories, aircraft, and Earth-orbiting satellites to learn about our environment. What do we call all these scientists? Oceanographers