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Book Chapter
Telephones, clothing, skis, antihistamines, ballpoint pens, music cassettes, toilet seats, antifreeze, and gasoline: What do these items have in common? All are often made from oil. The United States, like other industrialized nations, bases much of ...
Book Chapter
Hundreds of thousands of boats and ships and the materials and supplies on them have sunk to watery graves since humans first sailed the oceans. Even today, it is common practice for humans to throw their waste into the seas. In the past, much of tha...
Book Chapter
A substance’s molecular structure is responsible for its properties and governs how it interacts with other things on Earth. This Activity introduces and explores one specific property of liquid water. This sample chapter also includes the Table of...
Book Chapter
Water has many peculiar properties: high specific heat capacity, strong ability to act as a solvent, and the ability of the solid phase of water (ice) to float on its liquid phase. Many of the peculiar properties of water are directly related to the ...
Book Chapter
Water is one of the simplest chemical substances on Earth, and yet we must have it to live. In this Activity, you will learn how hydrogen and oxygen join and investigate some characteristics of the bond between them. Knowing the molecular structure o...
Book Chapter
The characteristics of the different parts of the ocean vary depending on the region. While the coastal ocean changes rapidly and presents the largest amount of biological activity, it also shows the largest exchanges with the continents through the ...
Book Chapter
Over and Under— Why Water’s Weird
Understanding water’s molecular structure helps explain some of its characteristics. Density is the mass of an object divided by its volume. In this Activity, you will look at how heating affects the density of different substances....
Book Chapter
The Tides: A Balance of Forces
The interaction between the gravitational forces of Earth, the Moon, and the Sun causes tides. The rhythmic movement of the water associated with the tides causes successive high and low waters in the coastal areas. ...
Book Chapter
Earth’s surface is mostly covered by water. Areas not covered by water—the continents—are surrounded by water. If land and water had the same specific heat, we would expect the land and surrounding water to heat up and cool down at the same rat...
Book Chapter
A wave is a disturbance that transmits energy from one location to another. In the ocean, most waves are created by the action of the wind over the surface. The interaction of the waves with the bottom near the shore causes the waves to break. Larger...
Book Chapter
Water is often called the universal solvent because so many substances will dissolve in it. Why do so many substances dissolve readily in water? In this Activity, you will explore the solubility of various substances in water as compared with other l...
Book Chapter
The ocean plays a fundamental role in many ways: from affecting the global climate and its variability, to phenomena such as El Niño, to the dispersal of pollutants such as oil spills. Understanding the dynamics controlling the ocean is essential to...
Book Chapter
If you have ever gone swimming in an ocean, or better yet, in Great Salt Lake, Utah, you may have noticed that it was easier to float in the ocean or in Great Salt Lake than in a pool or freshwater lake. Why is this? In the first part of this Activit...
Book Chapter
Ocean water is not the same everywhere. In some places, the water is colder or deeper than in other places. Some parts are denser or contain differing amounts of dissolved salts than other parts. All these things affect the way ocean water behaves. ...
Book Chapter
The Myth of Davy Jones’s Locker
For centuries, sailors believed that bodies buried or lost at sea did not sink to the bottom. They believed that a special depth existed between the surface and the bottom of the ocean where a body would remain suspended. Sailors called this region o...
Book Chapter
Estuaries — Where the Rivers Meet the Sea
An estuary is a body of water partially enclosed by land that has a connection to a river or stream, and an opening to the ocean. They are places where freshwater coming from rivers and streams mixes with salty ocean water. In this Activity, you will...
Book Chapter
Recycled Water: The Hydrologic Cycle
If we cannot see the water vapor, how do we know water vapor exists? In this Activity, you will examine the evidence regarding the presence of water vapor in the air and explore how water vapor plays a key role in the formation of clouds and rain....
Book Chapter
Lightning is not only visually spectacular; it is also dangerous. Lightning is one of the leading causes of weather-related deaths and injuries in the United States each year, not to mention damage to property. Knowing the properties of lightning,...
Book Chapter
In this Activity, students write an original, creative story about the movement of a water molecule through the hydrologic cycle....
Book Chapter
Measurement scales are standard values that can be used to compare properties. In meteorology, several scales may be used for the same quantity, depending on the purpose. For example, in the United States, temperature is frequently measured in ter...
Book Chapter
Have you ever looked up in the sky and seen a cloud in the shape of an animal? Regardless of the shape or size, certain conditions need to be present for a cloud to form. In this Activity, you will explore the conditions that must be present for clou...
Book Chapter
If you watch the local news, you have probably heard meteorologists talk about the humidity as well as the temperature. In this Activity, you will use the fact that the amount of water vapor at saturation depends on the temperature to determine how h...
Book Chapter
Snowflakes are made of ice. We think of ice as being frozen water. However, if you have ever seen a snowflake, chances are you have noticed that snowflakes do not look like most examples of frozen water we are used to seeing (e.g., ice cubes, icicles...
Book Chapter
Have you ever heard the word “muggy” used to describe the weather? How about the phrase “hazy, hot, and humid”? These phrases are used to describe times when there is considerable moisture in the air. In this Activity, you will measure humidi...
Book Chapter
The air inside a cloud can be very different from the air outside the cloud, not only because of the presence of cloud droplets and increased water vapor, but also in terms of density and temperature. In this Activity, students learn what types of cl...
Book Chapter
Meteorologists collect data from multiple weather stations and instruments on Earth’s surface. The weather maps seen online and on TV are analyzed pictures that are produced after the data analyses have been completed. Weather maps usually show the...
Book Chapter
Riding the Wave of a Hurricane
Hurricanes are the most destructive storms on Earth. Hurricanes contain tremendous amounts of energy. When it appears that a hurricane is moving toward land, the National Weather Service (NWS) issues hurricane watches and warnings. In this Activity, ...
Book Chapter
The atmosphere is made up of a variety of gases, but it is gases like water vapor and carbon dioxide, which make up a small fraction of the air, that have the biggest impact on us in terms of precipitation, pollutants, and global warming. The atmosph...
Book Chapter
In this Activity, you will explore how gases can be dissolved in a liquid or solid, what influences how those gases are released from the liquid or solid into the atmosphere, and how that process can be used to explain why there is as much oxygen in ...
Book Chapter
El Niño Southern Oscillation (ENSO)
ENSO refers to the periodic “shift” in sea surface temperatures across the equatorial Pacific Ocean that affects climate in a large portion of the world. The acronym ENSO comes from two such climate shifts, one known as El Nino (which corresponds...
Book Chapter
Although we usually cannot feel the air, there are times when the force of the air is obvious. Differences in air pressure influence the wind as well as cloud formation, and air pressure observations can help meteorologists predict weather patterns. ...
Book Chapter
The ozone layer refers to a region of the atmosphere about 15–30 km above Earth’s surface that contains a relative abundance of ozone (but still a tiny amount compared to the rest of the air). Ozone is a molecule containing three oxygen atoms (in...
Book Chapter
The Percentage of Oxygen in the Atmosphere
How do we know how much of each gas is in the atmosphere? We cannot see the individual atoms that make up the air and, even if we could, we would not be able to count all of the atoms to see which type of atom is most common. There are several ways t...
Book Chapter
Air Pollution and Environmental Equity
Airborne pollutants include “criteria” pollutants, such as ozone, particulate matter, carbon monoxide, nitrogen oxides, sulfur dioxide, and lead, and toxic pollutants like benzene and mercury. The Environmental Protection Agency (EPA) is charged ...
Book Chapter
At first, you may think the particles are the result of pollution. While much of the particulate matter in the atmosphere is the result of humans polluting the air, there are also natural sources of particles. Wind-blown dust and pollen are examples,...
Book Chapter
Weather and the Redistribution of Thermal Energy
The weather that we observe, like the variations in temperature, humidity, wind, and precipitation, is a consequence of the atmosphere’s response to differences in its temperature. In response to these differences, the air circulates and thermal ...
Book Chapter
Why Is It Hotter at the Equator Than at the Poles?
For locations close to the equator, the Sun can get close to directly overhead. For locations close to the poles, the Sun never gets far above the horizon. For some days of the year, the Sun never gets above the horizon at all. So, why is there a dif...
Book Chapter
Global Warming and the Greenhouse Effect
The “greenhouse effect” refers to how certain gases in the atmosphere (like carbon dioxide and water vapor) warm due to their absorption of infrared radiation emitted by Earth, leading to the surface of Earth being warmer than it would be with...
Book Chapter
Which Gets Hotter: Light or Dark Surfaces?
On sunny summer days, is it better to wear light-or dark-colored clothing if you are trying to keep cool? Which type of clothing is best to wear on cold, sunny winter days if you want to get warm quickly? You probably have answered some of these ques...
Book Chapter
Environmental Effects of Acid Rain
Acid rain refers to rain water that is slightly acidic due to the presence of air pollutants like sulfur dioxide and nitrogen oxides, much of which come from power plants and auto emissions. Acid rain impacts lakes and streams, trees and forests, ...