Sbsp affirmative- arl lab- ndi 2011
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AT: Ozone HoleOzone hole stable – no decline this centuryYang et al 2006 – Professor at Georgia Institute of Technology [Eun-Su, 3/22/06, Journal of Geophysical Research, “Attribution of recovery in lower-stratospheric ozone,” with experts from Jet Propulsion Laboratory/California Institute of Technology, Hampton University, NASA/Langley Research Center, Global Monitoring Division at NOAA Earth System Research Laboratory, University of Alabama at Huntsville, DS] Multiple satellite and ground-based observations provide consistent evidence that the thickness of Earth’s protective ozone layer has stopped declining since 1997, close to the time of peak stratospheric halogen loading. Regression analyses with Effective Equivalent Stratospheric Chlorine (EESC) in conjunction with further analyses using more sophisticated photochemical model calculations constrained by satellite data demonstrate that the cessation of ozone depletion between 18 and 25 km altitude is consistent with a leveling off of stratospheric abundances of chlorine and bromine, due to the Montreal Protocol and its amendments. However, ozone increases in the lowest part of the stratosphere, from the tropopause to 18 km, account for about half of the improvement in total column ozone during the past 9 years at Northern Hemisphere midlatitudes. The increase in ozone for altitudes below 18 km is most likely driven by changes in transport, rather than driven by declining chlorine and bromine. Even with this evidence that the Montreal Protocol and its amendments are having the desired, positive effect on ozone above 18 km, total column ozone is recovering faster than expected because of the apparent transport driven changes at lower altitudes. Accurate prediction of future levels of stratospheric ozone will require comprehensive understanding of the factors that drive temporal changes at various altitudes and partitioning of the recent transport-driven increases between natural variability and changes in atmospheric structure perhaps related to anthropogenic climate change. AT: VolcanoesVolcanoes are comparatively irrelevant – humans emit a hundred times moreGerlach, ’10 – emeritus geologist at the USGS, Cascades Volcano Observatory [Terry, 6/30/2010, Earth Magazine, “Voices: Volcanic versus anthropogenic carbon dioxide: The missing science,” http://www.earthmagazine.org/earth/article/371-7da-7-1e, DS] “Volcanoes add far more carbon dioxide to the oceans and atmosphere than humans.” So says geologist Ian Plimer of the University of Adelaide in his 2009 best seller “Heaven and Earth: Global Warming — the Missing Science.” With this assertion, Plimer brings volcanic carbon dioxide degassing front and center in the climate change debate, reviving and reinforcing this wildly mistaken notion. USGS Although discussions of volcanic carbon dioxide emissions make up less than 5 percent of “Heaven and Earth’s” text, the alleged predominance of volcanic over human carbon dioxide emissions is one of its most publicized takeaway messages. And one that will reverberate in the media and blogosphere — no matter how vociferously professionals who investigate volcanic carbon dioxide emissions bristle and huff about how appallingly at odds Plimer’s claim is with our research findings. The treatment of volcanic versus anthropogenic carbon dioxide emissions in this book illustrates one of the pathways by which myths, misrepresentations and spurious information get injected into the climate change debate. Like several climate skeptic publications, blogs and websites, “Heaven and Earth” does not provide the published estimates of the present-day global carbon dioxide emission rate from volcanoes. These estimates are, ironically, “the missing science” of a book professing to rectify supposed excesses of missing science — a book that appears impressively authoritative by citing a mountain of scientific literature. Several studies containing these estimates are among its 2,311 citations, but the estimates themselves are never divulged. Moreover, the book and other purveyors of this myth never explain, nor cite sources that explain, how it is known that volcanoes wholly outdo humans in adding carbon dioxide to the oceans and atmosphere. Published estimates based on research findings of the past 30 years for present-day global emission rates of carbon dioxide from subaerial and submarine volcanoes range from about 150 million to 270 million metric tons of carbon dioxide per year, with an average of about 200 million metric tons, These global volcanic estimates are utterly dwarfed by carbon dioxide emissions from fossil fuel burning, cement production, gas flaring and land use changes; these emissions accounted for some 36,300 million metric tons of carbon dioxide in 2008, according to an international study published in the December 2009 issue of Nature Geoscience. Even if you take the highest estimate of volcanic carbon dioxide emissions, at 270 million metric tons per year, human-emitted carbon dioxide levels are more than 130 times higher than volcanic emissions. Occasionally, scaled-down versions of the myth surface — for example, “Volcanoes produce more carbon dioxide than the world’s cars and industries combined.” The truth is that data from the Carbon Dioxide Information and Analysis Center of Oak Ridge National Laboratory and the International Energy Agency indicate that light-duty vehicles (cars, pickup trucks, SUVs, vans, wagons) contribute about 3,040 million metric tons of carbon dioxide per year, and industry adds another 6,100 million metric tons of carbon dioxide. The combined output is about 35 times greater than estimates of global volcanic carbon dioxide output. Another version of the myth is the all-powerful but poorly understood volcanic source. For example, “Heaven and Earth” describes submarine volcanoes as “poorly understood because of the lack of continuous observation and measurement,” yet “carbon dioxide from tens of thousands of submarine hot springs associated with these submarine basalt volcanoes quietly dissolves in the cold high-pressure deep ocean water.” Then, this statement: “One hot spring can release far more carbon dioxide than a 1,000-megawatt coal-fired power station yet they are neither seen nor measured.” If this is neither seen nor measured, then how does Plimer know how much carbon dioxide a hot spring emits? No supporting evidence or references are offered. In fact, there are measurements on the carbon dioxide flux of mid-ocean ridge hydrothermal fluids, but they do not support the power station comparison. According to the Environmental Protection Agency, the average carbon dioxide emission rate from coal-fired power generation in the United States is 1.02 metric tons per megawatt-hour. So, 1.02 metric tons of carbon dioxide per megawatt-hour, times 1,000 megawatts, times 24 hours per day, times 365 days per year, equals 8,935,200 metric tons of carbon dioxide per year. Thus, one of these submarine hot springs allegedly generates “far more” than 9 million metric tons of carbon dioxide per year — or far more than three times the annual baseline output of Kilauea Volcano in Hawaii! Just 12 of these hot springs would exceed carbon dioxide emission rate estimates for the entire 65,000-kilometer-long mid-ocean ridge system. To scale up volcanic carbon dioxide output to the current anthropogenic level would require adding thousands of volcanoes to the 50 to 60 normally active volcanoes of the subaerial landscape and more than a hundred additional mid-ocean ridge systems to the seafloor. Global volcanic carbon dioxide emission estimates contain uncertainties and are variable, but there is virtually no doubt that volcanism adds far less carbon dioxide to the oceans and atmosphere than humans. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 1.74 Mb. Share with your friends:
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