The Rate Debate Slowing
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- AT: Alt Cause - Clouds
- AT: Alt Cause - Cosmic Rays
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AT: Alt Cause - SunspotsHuman emissions, not the sun, are the primary cause of global warming – NASA satellites prove Parry 12 (Wynne Parry, LiveScience Senior Writer, 2/1/12, “NASA Report: Greenhouse Gases, Not Sun, Driving Warming” www.livescience.com/18255-solar-cycle-climate-change-warming.html) A recent, prolonged lull in the sun's activity did not prevent the Earth from absorbing more solar energy than it let escape back into space, a NASA analysis of the Earth's recent energy budget indicates. An imbalance like this drives global warming — since more energy is coming in than leaving — and, because it occurred during a period when the sun was emitting comparatively low levels of energy, the imbalance has implications for the cause of global warming. The results confirm greenhouse gases produced by human activities are the most important driver of global climate change, according to the researchers. They found that the Earth absorbed 0.58 watts of excess energy per square meter than escaped back into space during the study period from 2005 to 2010, a time when solar activity was low. By comparison, the planet receives 0.25 watts less energy per square meter during a solar minimum, than during a period of maximum activity in the sun's 11-year cycle. (Currently, the sun is in the midst of Solar Cycle 24, with activity expected to ramp up toward solar maximum in 2013.) "The fact we still see a positive imbalance despite the prolonged solar minimum isn't a surprise given what we've learned about the climate system," lead researcher James Hansen, director of NASA's Goddard Institute for Space Studies, said in a statement. "But it's worth noting, because this provides unequivocal evidence that the sun is not the dominant driver of global warming." AT: Alt Cause - CloudsCloud formations irrelevant - they are net coolants Baum et. al 12 (Seth Baum, Research on Environmental Decisions @ Columbia, Chris Karmosky, Geography @ Penn State, Jacob Haqq-Misra, Meteorology and Astrobiology Research Center, June 2012, "Climate Change: Evidence of Human Causes and Arguments for Emissions Reduction," Science and Engineering Ethics 18(2)) The Role of Cloud Formation Clouds do play an important role in surface air temperatures: water vapor is Earth’s most prevalent greenhouse gas, so increased cloud cover will cause surface warming. However, clouds also reflect incoming solar radiation back into space, thereby cooling Earth’s surface. In general, thick clouds, such as the cumulonimbus Evidence of Human Causes and Arguments 397 123clouds found in thunderstorms, tend to have a net cooling effect on Earth’s surface, whereas thin clouds, such as high cirrus clouds, have a net warming effect (Grenci and Nese 2006). Higher global temperatures will cause higher rates of evaporation, bringing more of both thick and thin clouds. Clouds thus constitute an important source of uncertainty in future temperature change. AT: Alt Cause - Cosmic RaysBaum et. al 12 (Seth Baum, Research on Environmental Decisions @ Columbia, Chris Karmosky, Geography @ Penn State, Jacob Haqq-Misra, Meteorology and Astrobiology Research Center, June 2012, "Climate Change: Evidence of Human Causes and Arguments for Emissions Reduction," Science and Engineering Ethics 18(2)) The Role of Cosmic Rays The amount of incoming radiation from both the sun and other cosmic ray sources is not constant over time. As Spier (2008) indicates, some researchers have claimed that these cosmic ray fluctuations are at least as dominant a driver of global temperature changes as greenhouse gas emissions, including via changes in cloud cover (Carslaw et al. 2002; Marsh and Svensmark 2000a, b). However, there is no apparent correspondence between the cosmic ray time series and global low-level cloud cover past 1994 (Kristjansson et al. 2002, 2004; Sun and Bradley 2002). Likewise, the overall contribution of solar variability to global radiative forcing is small relative to anthropogenic contributions (Solomon et al. 2007). AT: Alt Cause - VolcanoesVolcanic eruptions actually help slow down warming Eilperin 11 (Juliet Eilperin joined The Washington Post as the House of Representatives reporter, where she covered the impeachment of Bill Clinton, lobbying, legislation, and four national congressional campaigns, since April of 2004 she has covered the environment for the national desk, reporting on science, policy and politics in areas including climate change, oceans, and air quality, 7/21/11, “Volcanic ash, soot helped slow recent warming, study shows” www.washingtonpost.com/national/health-science/volcanic-ash-soot-helped-slow-recent-warming-study-shows/2011/07/20/gIQAg7k8RI_story.html) Tiny solid and liquid particles in the atmosphere, including volcanic ash and soot from fossil fuel burning, have kept the Earth from warming as fast as it otherwise would have in the past dozen years, according to a new study published online Thursday in the journal Science. The findings show that both natural and human factors have slowed the rate of global warming 20 percent since 1998. Small particles, otherwise known as aerosols, help cool the Earth’s climate by blocking out sunlight. The study is significant because although average global temperatures last decade were higher than in the 1990s and 1980s, it appears the rate of warming has slowed compared with previous decades. Now, scientists say, persistent aerosols in the stratosphere — the region of the atmosphere that contains the ozone layer — might account for why warming has not been as rapid. John S. Daniel, who co-authored the paper and is a research scientist at the National Oceanic and Atmospheric Administration’s Earth System Research Laboratory in Boulder, Colo., said the analysis shows the impact minor volcanic eruptions and soot from coal burning is “certainly not negligible.” By looking at both ground-based and satellite data, “you could see without a doubt volcanoes were having an impact” even though there has not been a colossal eruption since Mount Pinatubo erupted in 1991, Daniel said. The six researchers, from France and the United States, did not determine how much of the cooling effect stemmed from natural causes and how much was from human activities such as sulfur dioxide emissions from power plants and vehicles. Alan Robock, a professor at Rutgers University’s Department of Environmental Sciences who specializes in analyzing volcanic activity’s climatic impact, said the paper buttresses the argument that the climate change taking place is consistent with computer modeling. 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 0.98 Mb. Share with your friends:
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