Recycling is a very important way you can help preserve the world's forests.

The average temperature of the earth's surface has increased about 0.5 to 1.5 Fahrenheit degrees (0.3 to 0.8 Celsius degree) since the late 1800's. Scientists have not yet proved that an increasein atmospheric carbon dioxide has raised the surface temperature. But in the likely event that this relationship does exist, the eventual results could be severe. Many scientists estimate that, by about 2050, the amount of carbon dioxide in the atmosphere will have doubled from the preindustrial level. If this increase were to add to the natural greenhouse effect, the earth's surface temperature might rise between 3 and 8 Fahrenheit degrees (1.5 and 4.5 Celsius degrees) by 2100.

Scientists have examined evidence from the distant past to determine whether changes in carbon dioxide concentration cause temperature changes. Cores of ice drilled from great depths in Greenland and Antarctica provide a record for the past 160,000 years. During those years, the climate warmed and cooled several times. Researchers analyzed the gases and other substances that were trapped in the ice when it formed. During the cooler periods, the atmosphere contained about 30 percent less carbon dioxide and 50 percent less methane than during the warmer periods.

Today, severe deforestation occurs in tropical areas, primarily as a result of the clearing of land for agriculture and industry. Until the late 1940's, tropical rain forests covered about 6 million square miles (16 million square kilometers) of the earth's land. In the late 1980's, they covered only about 4 million square miles (10 million square kilometers). Scientists estimate that as many as 50 million acres (20 million hectares) of tropical rain forests are destroyed each year. Most of this destruction occurs in Latin America and Southeast Asia.

In other parts of the world, industrial pollution is a chief cause of deforestation. Factories often release poisonous gases into the air and dangerous wastes into lakes and rivers. Air pollutants may combine with rain, snow, or other precipitation and fall to earth as acid rain. These pollutants can restrict plant growth in a region and eventually kill most plants there. In parts of Europe, forest areas set aside long ago for continuous timber production have been seriously damaged by industrial pollution. Pollution also threatens forests in eastern North America. ²

The earch is our home, an island in space. Let's respect the rain forests, and put an end to deforestation!

Sustainable Ecosystems

Wild species of animals and plants provide many valuable substances, such as wood and other plant products, fibers, meat and other foods, and skins and furs. The financial value of wild species is important to the economies of many nations. Every species of wildlife plays a role in helping maintain the balanced, living systems of the earth. These systems must continue to function if life is to survive. Thus, the loss of any species can threaten the survival of all life, including human beings.³