 |  Environmental Science: A Global Concern, 7/e William P. Cunningham,
University of Minnesota
Mary Ann Cunningham,
Vassar College
Barbara Woodworth Saigo,
St. Cloud State University
Air, Weather, and Climate
Chapter OverviewFor humans and many other species, the atmosphere provides the most precious resource of all: molecular oxygen. The good news is that, amid a plethora of major air-quality problems, running out of atmospheric oxygen is not one of them.
However, the atmosphere is far more involved with human and ecosystem well-being than with simply providing oxygen. The atmosphere is a central part of the hydrologic, carbon, and nitrogen cycles. It is the layer through which electromagnetic energy from space, including sunlight, must pass.
The atmosphere is also a gigantic weather engine powered by energy input from the sun. It moves water and heat around the earth in massive amounts in ways that dictate global climates. We have recently learned that world climates have long fluctuated between warmer and cooler periods and, in general, are less stable than we previously thought.
Recent studies reveal that human activities themselves appear capable of producing change in global climate. If the models are correct, human activities may have already begun to produce one of the more rapid climatic changes in the earth's history. Potential consequences are severe for both the natural and the human-made world.
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2003 McGraw-Hill Higher Education