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Tuesday, 19 February 2008 |
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Global Warming is caused by many things. The causes are split up into two groups, man-made or anthropogenic causes, and natural causes. Natural Causes Natural causes are causes created by nature. One natural cause is a release of methane gas from arctic tundra and wetlands. Methane is a greenhouse gas. A greenhouse gas is a gas that traps heat in the earth's atmosphere. Another natural cause is that the earth goes through a cycle of climate change. This climate change usually lasts about 40,000 years. Man-made Causes Man-made causes probably do the most damage. There are many man-made causes. Pollution is one of the biggest man-made problems. Pollution comes in many shapes and sizes. Burning fossil fuels is one thing that causes pollution. Fossil fuels are fuels made of organic matter such as coal, or oil. When fossil fuels are burned they give off a green house gas called CO2. Also mining coal and oil allows methane to escape. How does it escape? Methane is naturally in the ground. When coal or oil is mined you have to dig up the earth a little. When you dig up the fossil fuels you dig up the methane as well. |
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Last Updated ( Thursday, 03 July 2008 )
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Saturday, 16 February 2008 |
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In many tropical countries, the majority of deforestation results from the actions of poor subsistence cultivators. However, in Brazil only about one-third of recent deforestation can be linked to "shifted" cultivators. Historically a large portion of deforestation in Brazil can be attributed to land clearing for pastureland by commercial and speculative interests, misguided government policies, inappropriate World Bank projects, and commercial exploitation of forest resources. For effective action it is imperative that these issues be addressed. Focusing solely on the promotion of sustainable use by local people would neglect the most important forces behind deforestation in Brazil.
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Last Updated ( Thursday, 03 July 2008 )
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Saturday, 16 February 2008 |
As the first seven sections of this site have described, tropical rainforests are incredibly rich ecosystems that play a fundamental role in the basic functioning of the planet. Rainforests are home to probably 50 percent of the world's species, making them an extensive library of biological and genetic resources. In addition, rainforests help maintain the climate by regulating atmospheric gases and stabilizing rainfall, protect against desertification, and provide numerous other ecological functions. 
However, these precious systems are among the most threatened on the planet. Although the precise area is debated, each day at least 80,000 acres (32,300 ha) of forest disappear from Earth. At least another 80,000 acres (32,300 ha) of forest are degraded. Along with them, the planet loses as many as several hundred species to extinction, the vast majority of which have never been documented by science. As these forests fall, more carbon is added to the atmosphere, climactic conditions are further altered, and more topsoil is lost to erosion. |
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Last Updated ( Thursday, 03 July 2008 )
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Saturday, 16 February 2008 |
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Greenhouse gases Carbon Dioxide levels in the Earth's atmosphere have increased by 30% in the last 200 years alone. Concentrations of greenhouse gases in the atmosphere are currently at their highest for 800,000 years. Temperatures  Global temperatures have risen by over 0.7C since the 1700s with 0.5C of this warming occurring during the past 100 years. The warmest decade of the last millennium was the 1990s with four out of five of the warmest years ever recorded occurring during the decade. 1998 was the warmest year globally since records began in 1861. Water Average global sea levels have increased by between 0.1 and 0.2 metres over the last 100 years as a result of heavier rainfall, melting artic ice sheets and water expanding due to warmer temperatures. The frequency and severity of drought conditions has increased in Asia and Africa in the past few decades. Predictions The Intergovernmental Panel on Climate Change (IPCC) predicts a probable global temperature rise of between 1.8C and 4C (3.2-7.2F) by the end of the century if current levels of greenhouse gas emissions continue. The IPCC states that possible global temperature changes by the end of the century could be as high as 6.4C.Sea levels around the world are likely to rise by 28-43cm by the end of the century. Arctic summer sea ice is likely to disappear in second half of century An increase in the number of heatwaves and tropical storms are expected in parts of the world.  Human activities
The world population has grown by more than 2.5 times in the past 55 years from 2.5 billion in 1950 to 6.45billion in 2005. Global energy demands are projected to rise by as much as 60% in the next 20 years as a result of continued population growth and economical, commercial and social development. |
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Last Updated ( Thursday, 03 July 2008 )
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Saturday, 16 February 2008 |
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One of the most current and widely discussed factor which could lead to the ultimate end of existence of Earth and man is global warming and its devastating effects. Scientists have asked how fast the Earth is heating up, and how the warming effects on Earth may effect crops and climatic conditions. Several current trends clearly demonstrate that global warming is directly impacting on; rising sea levels, the melting of icecaps, and significant worldwide climatic changes. This paper will discuss the degree of destruction caused by global warming, contributing factors to warming, and finally, discuss what we can do to decrease the current rate of global warming. I would also like to present opposing viewpoints to the effects of the warming process. In my understanding, global warming represents a fundamental threat to all living things on earth.  |
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Last Updated ( Thursday, 03 July 2008 )
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Climate Change 
