effect. The increase in greenhouse gasses from human sources comes from a variety of things. Elevated Co2 levels, which have been increasing at a rate of 0.5% per year, largely come from the burning of fossil fuels(70-75%), especially coal. Deforestation and plant burning account for the remainder. Increased Methane and Nitrous oxide in the atmosphere are mostly due to agriculture; rice patties, cattle, termites and decomposition of dead tissue. The improper burning of natural gas, natural gas leeks from oil and gas production and pipelines also contribute to these elevated levels. CFC’s and PFC’s are a purely human addition to the atmosphere. Air conditioners, refrigeration, and plastic foam production account for these elevations.A small change in climate can cause a great deal of change. Many biomes would seriously be affected. A 10C change in climate would cause a 100 mile shift in biomes from the equator. This shift would cause serious economic and humanitarian problems in the United States. Scientists predict by 2100 a climate change of between 10c,at best and a 3.50c, at worst, could happen. Lets assume say a 20c climate change were to occur. A 200 mile shift in the crop band would occur, putting the nations breadbasket largely in Canada, devastating the U.S. economy. The tundra soil of Canada not being as good for agriculture as the plains and rolling hill of the middle eastern United States and the lack of established agribusiness could account for a 10 to 50 decrease in food production. Rain and weather patterns would shift, causing many cities to be relocated. Hurricanes, droughts, flooding and other severe weather would be more prevalent due to increased water vapor in the atmosphere. A severe impact on forestation and biodiversity would occur. Evolutionary adaptation to the new climate takes time and the mile per year movement of forests would not be able to out run it. Aquatic systems would b...
