What is today’s Anthropogenic Radiative Forcing? www.assignmentpoint.com

CO2 causes most of the positive radiative forcing of climate, but the sum of the other greenhouse gases is comparable. Aerosols generally cool and are the source of greatest uncertainty in radiative forcing since the pre-industrial era. www.assignmentpoint.com

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Temperature comparison with and without greenhouse gases and sulphur (NCAR/DOE) www.assignmentpoint.com

NCAR/DOE conclusions on temperature models “Solar activity contributed to a warming trend in global average temperature from the 1910s through 1930s. As industrial activity increased following World War II, sun-blocking sulfates and other aerosol emissions helped lead to a slight global cooling from the 1940s to 1970s. Since 1980, the rise in greenhouse gas emissions from human activity has overwhelmed the aerosol effect to produce overall global warming. “ www.assignmentpoint.com

Global Warming Effects Predicted Global Warming of 5°F will affect everyone in most structural aspects of society and in their costs. We don’t realize how our present housing, business, and supply nets are closely adapted to our current climates. The major increase in temperature and climate effects such as rainfall, drought, floods, storms, and water supply, will affect farming, year round water supplies, household and business heating and cooling energy. These may require large and costly modifications. Some cold areas may benefit, and some hot areas will become unfarmable and costly to inhabit. Recent projection: US agriculture would go up 4%, CA down 15%. Methane production seems to have stabilized (UCI result) It is very misleading to portray the problem as a purely environmentalist issue which affects only polar bears, a few Pacific islanders, and butterflies. www.assignmentpoint.com

What can be said about the controversy? Here are some comments. 17 national science academies have endorsed the conclusion of global warming and its man-made causes. The Intergovernmental Panel for Climate Change (IPCC, www.ipcc.ch ), consulting 2,500 scientists from 130 countries, will issued a new report on Feb. 2, after six years, which states a 90-99% probability that warming since 1950 is human caused. It has also concluded a >90% probability that temperatures will continue to rise. www.assignmentpoint.com

What can we reasonably say about fossil fuels and global warming? Global warming of 1° F has occurred in the past century. CO2 is a greenhouse gas and is way higher than it has historically been. This is generated by human burning of fossil fuel, but fortunately, half of that generated has been absorbed in the carbon cycle. Common sense, models of earth systems, and the correlation of warming with CO2 in ice ages, indicate a direct effect between the two. Clearly, funding much more research on this is clearly justified. Since we are going to run out of cheap fossil fuel this century, research on new energy sources, and plans to develop them are clearly called for. www.assignmentpoint.com

Arguments against global warming and its man-made causes 1. Global warming doesn’t exist There is one location which hasn’t warmed The Antarctic ice is growing in thickness Michael Crichton’s State of Fear 2. Global warming is a natural cycle and not caused by humans (and will go away?) Answer: But temperature changes must have a cause. All of the known causes are included in the models, and human made causes dominate. Users of this symantic out never propose a “natural” cause. 3. Other objections to man-made origins: The dip in the 50s in the temperature curve How can ppm of CO2 have any effect Breathing creates CO2 The temperature always fluctuates You can’t predict next week’s weather, so how can you … Water vapor is more important www.assignmentpoint.com