Mitigation Strategies and Solutions Essay Example | Topics and Well Written Essays - 1750 words

Mitigation Strategies and Solutions - Essay ExampleKemp (2004) estimates that the earths rebel temperature have increased by 0.3c-0.6c since 1900. The years 1995-2006 ranked amongst 11 of the twelve warmest years on record since climatic records began in 1850. The IPCC also estimates that by 2020, the earths temperatures will have ascensionn by a further 0.2c. Natural Causes/Contributions of Global Warming Earths Orbital Variation The Milankovitch Theory of climate change predicts that the Earths orbit close to the sun is not a perfect circle but an ellipse, which makes the earth closer to the sun at certain periods. This currently occurs in January, making Union hemisphere winters slightly milder than previous winters. With greater eccentricity the length of the Earths seasons varies, which can lead to the build up of ice sheets when there atomic number 18 tankful summers. Sun Spot Activity The sun is now believed to be its most active for 300 years (Kemp, 2004). In the past 120 years, 0.5c rise in global temperatures occurred before 1940, which is earlier than the biggest rise in greenhouse gas (GHG) emissions released by humans. Further evidence comes from tree ring data in which 17 out of 19 of the warmest spells in the past 10,000 years coincided with peaks in solar activity (Goudie, 2000). Ocean Circulation Changes The Earths oceans cover around 70% of the Earths surface and fawn twice the amount of suns radiation as the atmosphere of the land surface (Jackson and Jackson, 1996). With their huge modify capacity, and means to move vast quantities of heat across the planet, they have a major effect on the earths temperatures, e.g. during an El Nino cycle, the west microscope slide of South America experiences higher temperatures with greater rainfall due to the transportation of warm waters from the South Pacific replacing the usual up-welling of nutrient blue cooler waters (Thomas and Goudie, 2000). The North Atlantic Jet and Gulf Stream also ha s a major affect on the earths surface temperatures in North Europe, which transports warm heat from the Caribbean up to high latitudinal regions making temperatures artificially high for their latitudinal position. Human Causes/Contributions of Global Warming tan of Fossil Fuels The burning of fossil fuels such as coal, oil and gas releases anthropogenic emissions of GHGs, such as carbon dioxide, methane, nitrous oxide and halocarbons. These gases absorb some of the unseeable radiation emitted by the Earth which would otherwise escape back into space. This creates the enhanced greenhouse effect, in which increased CO? levels (280ppm from pre industrial levels to 379pmm by 2005) have warm global temperatures by around 0.5c over the past century (IPCC, 2007) Deforestation The worlds forests have decreased by around 38% over the past century (Jackson and Jackson, 1996). This has led to increased levels of CO? in the earths atmosphere because there are not enough trees to absorb the additional carbon rates caused by increased human activity. Increased agriculture and livestock such as cows release significant amounts of methane, which get towards global warming. Levels of methane have doubled since pre-industrial times to 1.765 ppmv (Kemp, 2004). CFCs CFCs and other halocarbons released from refrigerators, insulating foams, aerosol spray cans and industrial plants all destroy the stratospheric ozone, and are a significant cause of global warming due to their higher concentration levels of greenhouse gases (Goudie, 2000). Positive and Negative