Early predictions of global warming co2s greenhouse

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Unformatted text preview: greenhouse gases." Too Much Greenhouse Gas is Bad! As the concentraMons of these gases conMnue to increase in the atmosphere, the Earth's temperature is climbing above levels of recent past. Early Predictions of Global Warming CO2’s greenhouse effect was known to 19th century scientists such as the Swedish chemist, Svante Arrhenius. He was aware that burning coal was adding to the atmospheric concentration of CO2. Arrhenius made a calculation for doubling the CO2 in the atmosphere, and estimated it would raise the Earth's temperature some 5-6˚C. He did not see that as a pressing problem, figuring that if industry continued to burn fuel coal at the current (1896) rate, it would take perhaps three thousand years for the CO2 level to rise so high. Where are we now? 396.8 ppm in May 2012 levels recorded at observatory in Hawaii Recall that CO2 levels had been steady at 280 ppm for thousands of years Global warming is a reality Over the last century, the average temperature has climbed about 0.6°C. The 2000’s were the warmest decade in the past thousand years; 2010 was the 2nd hottest year ever recorded; the eleven hottest years on record all occurred since 1998, and the 15 hottest since 1995. The USA in 2012 •  The US recorded its warmest January-June period on record, and its warmest 12 month period •  In June, average daily temp for lower 48 states was 2.0 °F above the 20th century average •  Daily record high temperatures have outpaced daily record lows by an average of 2 to 1. –  If climate were not warming, should be 1:1 ratio. Is there a distinction between climate change and global warming? •  Climate change refers to any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). According to the National Academy of Sciences, “the phrase ‘climate change’ is growing in preferred use to ‘global warming’ because it helps convey that there are other changes in addition to rising temperatures.” Climate vs. weather •  Difference is a measure of time –  Weather: conditions of the atmosphere over a short period of time –  Climate: how the atmosphere behaves over relatively long periods of time; the prevailing long-term weather conditions in an area •  Climate change: changes in long-term averages Geochemical cycles or human activity? 396.8 ppm in May 2012 Model with natural AND anthropogenic fo...
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This test prep was uploaded on 03/20/2014 for the course BIOLOGY 171 taught by Professor Hunter during the Fall '09 term at University of Michigan.

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