Global Warming is a big problem in today¡¦s society. Global Warming also known as the Greenhouse effect is a problem everyone will soon have to face. The people of the younger generations should be educated about what Global Warming is and that it is caused due to the way people are treating the environment.
We are now entering the Greenhouse century as we know it. Planet Earth is estimated to be 4.5 billion years old, and life on earth has existed for more than 3.5 billion years. Humans have been on earth for 2 to 3 million years. It is only been in the past 200 years people have been affected by global warming. The last 40 years have been the most damaging.
As the impacts of human influences have grown, so have the risks associated with those impacts. New technologies carry increasing risks, and the scale, frequency, and impacts of disaster caused or influenced by human activity are growing tremendously. The risks to the Earth¡¦s natural systems are becoming significantly concerning.
The world¡¦s population, currently 5.2 billion has grown from about 3 billion in 1960, and around 2 billion in 1925. Today it increased by almost 90 million each year, and is likely to reach 10 billion by 2025(Corson 4).
The reason we currently have an atmosphere crisis is because of human impact on the gases which make up our atmosphere. Our atmosphere, which is made up of four distinct layers blankets our planet and protects up in many way. One way it protects us if from the harmful rays the sun radiates on our planet. Each layer differs from the others in temperature, density, composition and in the way it absorbs radiation from the sun. The atmosphere itself is some 300 miles thick. The first layer is the Troposphere. It is the lowest layer and extends higher than any airplane can travel, about 6.8 miles. Air in this layer is heated by the earth itself and for every 1000 feet the temperature drops 3.5 „a F. When it reaches the top of this layer the temperature is about - 70„a f. The next layer extends to about 30 miles. It is less dense than the underlying layer. Unlike the troposphere, temperature increases with altitude. This warming is caused by a layer of ozone.
Ozone is a form of oxygen. The ozone absorbs most of the sun¡¦s ultraviolet radiation. This has two important effects, First, it warms the air in the stratosphere. Second, it prevents much of the harmful rays from reaching the earth surface. Temperature in the layer reaches 29„a f.
The next few layer have almost no ozone or any water vapors. Air is less dense here and not even sound travels well here.
Carbon Dioxide comprises only a small portion of the atmosphere. A little more than 0.03%.
It is colorless, odorless gas yet vitally important to life on earth. Actually too much Carbon Dioxide can be just as dangerous as too little. Carbon Dioxide molecules have the ability to absorb heat energy. The greater amount of carbon dioxide, the greater amount of heat absorbed. The heat absorbed remains in the atmosphere rather than being radiated back into space. The result is higher temperatures on earth¡¦s surface. There are many signs that the levels of Carbon Dioxide in our atmosphere is increasing. This threatens the balance between the amount of solar energy reaching the earth.
Breathing for humans consists of taking in oxygen and getting rid of waste gases such as Carbon Dioxide. Carbon Dioxide is a byproduct of many industrial processes, including the fermentation of sugars to produce alcohol, the decomposition of limestone to make quicklime and the manufacture of cement. But the main sources are the burning of fossil fuels and the destruction of forests.
Because plants themselves need Carbon Dioxide Through photosynthesis plants absorb Carbon Dioxide and act as a natural defense against global warming. But there is a problem...people are destroying forests at an alarming rate. This deforestation increases Carbon Dioxide in the atmosphere in two ways. One with out the forests, Carbon Dioxide that would have been absorbed for photosynthesis remains in the air. The other is when the forest is burned or if trees decay after cutting them down, they release the carbon they have absorbed over their entire lifetime.
Burning fossil fuels pours huge amount of carbon dioxide and other heat-trapping gases into the atmosphere. About 5.6 Billion tons a year! The increasing amount of carbon dioxide in the atmosphere allows solar energy to pass through and prevents heat given off the earth form escaping into space. Other gasses affect the atmosphere come from many sources including CFCs from aerosol cans, refrigerants and cleaning solvents. This damaging cycle is called The Greenhouse Effect.
The growth of human numbers and their impacts on the earth¡¦s resources have greatly accelerated since World War II. The production of food, energy, and industrial commodities is associated with much of the deterioration of the Earth¡¦s life-support systems.
Some of the ways that Earth may respond to global warming could be gradual or could be rapid. By continuing to add greenhouse gases to the air we may be surprised by some climate changes. As an example when the Arctic warms, huge amounts of methane now trapped under ice could escape into the air. Methane is a Greenhouse gas that traps heat in the atmosphere, these added emissions could cause the Earth to warm even faster than now expected.
Part of the West Antarctic ice sheet precariously rest on the sea floor. As the sea warms, the ice might become destabilized, break up and melt. As a result over the next 300 years sea level would rise faster than currently predicted. Warmer water temperatures might lead to changes in the course of major ocean currents. Their paths determine the distribution of ocean temperatures and nutrients that sustain marine life. If the currents were to change direction, entire marine ecosystems could be disrupted.
It is known that plants and animals are being pushed to extinction. Also it is known about the role in raising the Earth¡¦s temperature. However no one knows how the two are connected. Global Warming may be proved to be the single threat to fellow species.
Vast quantities of pollutants are pouring into the atmosphere , posing health threat to humans, damaging the environment and changing the Earth¡¦s climate. Historically, the air has renewed itself through interaction with vegetation and the oceans. Today, however, this process is threatened by increasing use of fossil fuels, expanding industrial production, and growing use of motor vehicles.(Corson 220)
The most common and widespread pollutants currently emitted by human activities are sulfur dioxide, nitrogen oxides, carbon monoxide, carbon dioxide, volatile organic compounds particulate. Dozens of toxic chemicals are commonly found in the air surrounding urban areas.
In recent years, many industrial nations have controlled air pollution with some success. Europe and North America are now suffering serious damage from acid deposition. Increasing pollution from the growing use of motor vehicles plagues many nations. Car sales in Western industrialized nations rose 71 percent from 1970 to 1986.
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