Global Warming 4

Global Warming

Human kind has entered a brand new relationship with the earth. The constant and increasing pressures we are exerting threaten our planets ability to sustain life itself. Change-in the way we think , and in the way we live-is needed now.Global warming is the most urgent environmental problem the world will face in the next decade and the next century. Few, if any, trends are more important to our future than climate change caused by human activities. Scientist around the world are warning us that global warming poses a major threat to our future quality of life, previously there has been little information on this problem. Right now, the rate of global warming may be 100 times faster than it has ever been. Very soon the earth may become hotter then
at any time in human history. In the last decades the problems of atmospheric change have been gravely advanced by pollution resulting from human activities. These environmental changes pose a real threat to the lives of people and wild life.It is vital to all of us that we fully understand the complex relationship between the atmosphere and the earth. The earth is getting warmer. the changes are small, so far, but they are expected to grow and speed up. Within the next 50 to 100 years, the earth will continue to heat up hotter than it has been in the past
million years. As oceans warm and glaciers melt, land and cities along coasts may be flooded. Heat and drought may cause forests to die and food crops to fail. Global warming will effect weather everywhere, plants and animals everywhere and people everywhere. Humans are warming the earth¹s atmosphere by burning fuels, cutting down forests, and by taking part in other activities that release certain heat- trapping gasses into the air. Humans all over the world need to get together and solve these problems.In the southern hemisphere, the warming is the greatest over Australia, southern south Africa, the southern tip of south America, and the area of Antarctica near Australia. In the northern hemisphere, warming is strongest in Alaska, northwest and eastern Canada, most of the Soviet Union, and parts of Southern Asia, North Africa and south west Europe. Climate has cooled in Great Britain and northern and
eastern Europe. In the USA scientists found no overall warming trend in weather records kept since the nineteenth century, however keep in mind the United States covers only 1.5 percent of the earth¹s surface. As warming continues, every place on the earth will be effected.In the frozen heart of the last ice age, 18,000 years ago, the temperature was only about nine degrees Fahrenheit colder then today. So a change of a few degrees can have a dramatic effects. Today's most sophisticated climatic models estimate the global temperature will rise between 3 and 9 degrees Fahrenheit in the next century.This could occur as early as the year 2050. Here are the large scale changes the rise might bring: As water warms it expands, taking up more space. So warmer ocean water, with added melt-water from glaciers, will rise by twenty inches to five feet in the next 50 to 100 years.Just a 1 foot rise in sea level can cause shorelines to recede a hundred feet, and in flat terrain, a thousand feet. If ocean waters rise several feet, whole beaches could wash away. Many homes, hotels, other
buildings, and entire cities will be threatened. Salt water will pollute freshwater wells that millions of people use for drinking water. Coastal marshes, which are vital nurseries for fish and other ocean life will be endangered. Along undeveloped coast, marshes may survive because they can move inland with the rising waters. In many places seawalls and other human structures will prevent this process and the marshes will be destroyed. In the United States ocean water may cover the Florida Keys and large parts of southern Florida and Louisiana.Two kinds of action are called for. One is to take steps to prepare for the the effects of warming that already have begun. Agricultural scientist must develop varieties of wheat and other crops that can grow in a longer but drier growing season. Ways must be fond to use irrigation water more effectively. Conservation will also be important for drinking water supplies.Governments that control building and other development along coasts must begin to plan for rising sea levels. In the United States, billions of dollars have been spent to replace send eroded from beaches, and to help owners of beach front homes rebuild after storm damage. The states of Maine and North Carolina now prohibit permanent buildings on threatened beaches.