The Rate Debate Slowing
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- Oceans Check - AT: They Run Out
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Oceans CheckWarming would be slow – ocean absorption solves Roe & Bauman 11 (Gerald Roe, Department of Earth and Space Sciences, University of Washington, AND Yoram Bauman, Professor, Program on the Environment, University of Washington, 1-1-2011, “Should the climate tail wag the policy dog?”) A key player in the physical system is the enormous thermal inertia represented by the deep ocean. The whole climate system cannot reach a new equilibrium until the deep ocean has also reached equilibrium. In response to a positive climate forcing (i.e., a warming tendency), the deep ocean draws heat away from the surface ocean, and so buffers the surface temperature changes, making them less than they would otherwise be. The deep ocean is capable of absorbing enormous amounts of heat and not until this reservoir has been exhausted can the surface temperatures attain their full equilibrium values. A second key player is the inherent relationship between feedbacks and adjustment time scales in physical systems. If it transpires that we do in fact, live on a planet with a high climate sensitivity, it will be because we live on a planet with strong positive feedbacks. In other words, the net effect of all of the dynamic processes (clouds, water vapor, ice reflectivity, etc.) is to strongly amplify the planet's response to radioactive forcing. In this event, it would mean that we live on a planet that is inefficient in eliminating energy perturbations: a positive feedback reflects a tendency to retain energy within the system, inhibiting its ultimate emission to space, and therefore requiring a larger temperature response in order to achieve energy equilibrium. Moreover. it is generally true that, all else being equal, an inefficient system takes longer to adjust than an efficient one. A useful rule of-thumb is that the relevant response time of the climate system is given by the effective thermal inertia of the deep ocean multiplied by the climate sensitivity parameter (defined as AEX/AR" , see. eg., Roe. 2009). This behavior is absolutely fundamental and widely appreciated (e.g., Hansen et al.. 1985: Vlligley and Schlessinger. 1985). As time progresses, more and more of the ocean abyssal waters become involved in the warming, and so the effective thermal inertia of the climate system increases. Hansen et al. (1985) solve a simple representation of this effect and show that the adjustment time of climate is proportional to the square of climate sensitivity. In other words, if it takes 50 yrs to equilibrate with a climate sensitivity of 1.5°C, it would take 100 times longer, or 5,000 yrs to equilibrate if the climate sensitivity is 15°C. Although Nature is of course more complicated than this (see eg., Gregory, 2000), the basic picture described here is reproduced in models with a more realistic ocean circulation. In particular see results Held et al. (2010) for results from fully-coupled global climate models. In the context of the PDF of climate sensitivity, its effects have been reviewed in Baker and Roe (2009). Oceans Check - AT: They Run OutReaching ocean carbon sink capacities take centuries Cherubini et al. (FRANCESCO CHERUBINI*, GLEN P. PETERSw, TERJE BERNTSENwz, ANDERS H. STRØMMAN*andEDGAR HERTWICH* *Department of Energy and Process Engineering, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway, wCenter for International Climate and Environmental Research – Oslo (CICERO), Oslo, Norway, zDepartment of Geosciences, University of Oslo, Norway) 2011 (Francesco, “CO2 emissions from biomass combustion for bioenergy: atmospheric decay and contribution to global warming,” GCB Bioenergy (2011) 3, http://onlinelibrary.wiley.com/doi/10.1111/j.1757-1707.2011.01102.x/full, Page 415) //CL *Note in this article “C” refers to carbon as indicated by the author at the beginning C cycle climate models. CO2 emissions play a key role in the earth’s C cycle and climate system. Those which are classified as anthropogenic (i.e. from fossil fuel combustion, cement production, deforestation and land-use change) are one of the main responsible for anthropogenic climate change (Forster et al., 2007). Complex C cycle climate (CC) models, which establish the link between atmospheric CO2 concentration and anthropogenic C emissions by modeling uptake and exchange fluxes of the atmosphere with the oceans and the terrestrial biosphere, are used to model the time evolution of airborne CO2. In order to make analysis easier for smaller case studies, such as LCA, impulse response functions (IRF) are often used to represent CO2 atmospheric decay under given assumptions (Tubiello & Oppenheimer, 1995; Joos & Bruno, 1996; Enting et al., 2001). The oceans play an important role for the removal of anthropogenic C. They are generally distinguished into the upper layer, which has a very fast turnover rate (Wanninkhof, 1992), and the deep ocean, to which C is transported through oceanic circulation (Joos, 2003). This latter process is the limiting factor for the ocean’s uptake capacity, which is determined by ocean volume and sea water chemistry. This uptake capacity is only reached after several centuries, and it takes millennia to equilibrate ocean water and sediments after a perturbation in oceanic C content. Changes in the land biosphere and in the upper ocean influence atmospheric CO2 concentrations on seasonal to century time scales. Several models dealing with the C cycle in the oceans have been formulated (Oeschger et al., 1975; Siegenthaler & Joos, 1992; Blanke & Delecluse, 1993; Caldeira & Kasting, 1993). Sulfur Dioxide TurnEmissions removal causes warming – so2 cools the earth Prinn et al 5 — (Ronald G. Prinn, John Reilly, Marcus Sarofim, Chien Wang and Benjamin Felzer, MIT Joint Program on the Science and Policy of Global Change, January 2005, http://18.7.29.232/bitstream/handle/1721.1/7510/MITJPSPGC_Rpt118.pdf?sequence=1) The impact of these various pollutant caps on global and hemispheric mean surface temperature and sea level changes from 2000 to 2100 are shown in Figure 6 as percentages relative to the global-average reference case changes of 2.7°C and 0.4 meters respectively. The largest increases in temperature and sea level occur when SOx alone is capped due to the removal of reflecting (cooling) sulfate aerosols. Because most SOx emissions are in the northern hemisphere, the temperature increases are greatest there. For the NOx caps, temperature increases in the southern hemisphere (driven by the CH4 increases), but decreases in the northern hemisphere (due to the cooling effects of the O3 decreases exceeding the warming driven by the CH4 increases). For CO and VOC reductions, there are small decreases in temperature driven by the accompanying aerosol increases and CH4 reductions, with the greatest effects being in the northern hemisphere where most of the CO and VOC emissions (and aerosol production) occur. When NOx, CO, and VOCs are all capped, the nonlinearity in the system is evidenced by the fact that the combined effects are not simple sums of the effects from the individual caps. Ozone decreases and aerosol increases (offset only slightly by CH4 increases) lead to even less warming and sea level rise than obtained by adding the CO/VOC and NOx capping cases. Finally the capping of all emissions yields temperature and sea level rises that are smaller but qualitatively similar to the case where only SOx is capped, but the rises are greater than expected from simple addition of the SOx-capped and CO/VOC/NOx-capped cases. Nevertheless, the capping of CO, VOC and NOx serves to reduce the warming induced by the capping of SOx. Note that these climate calculations in Figure 6 omit the cooling effects of the CO2 reductions caused by the lessening of the inhibition of the land sink by ozone (Figure 5). This omission is valid if we presume that anthropogenic CO2 emissions, otherwise restricted by a climate policy, are allowed to increase to compensate for these reductions. This was the basis for our economic analysis in the previous section. To illustrate the lowering of climate impacts if we allowed the sink-related CO2 reductions to occur, we show a sixth case in Figure 6 (“allcap+sink”) which combines the capping of all air pollutant emissions with the enhanced carbon sink from Figure 5. Now we see that the sign of the warming and sea level rise seen in the “allcap” case is reversed in the “allcap+sink” case. If we could value this lowering of climate impacts, it would provide an alternative to the economic analysis in section 4.3. That SO2 is key to global cooling OSU 92 (Department of Geoscience, Oregon State University, http://volcano.oregonstate.edu/book/export/html/156) Symonds, Rose, Bluth, and Gerlach concluded that stratospheric injection of sulfur dioxide (SO2) is the principal atmospheric and global impact of volcanic eruptions via SO2 + OH + 3H2O -> H2SO4 (l) + HO2 The SO2 converts to sulfuric acid aerosols that block incoming solar radiation and contribute to ozone destruction. The blocked solar radiation can cause global cooling. The amount of SO2 released by volcanoes is much less compared to man-made sources but the impact of some eruptions might be disproportionately large. The gases emitted by most eruptions and by man-made sources never leave the troposphere, the layer in the atmosphere from the surface to about 10 km. However, volcanic gases reach the stratosphere, a layer in the atmosphere from about 10 km to about 50 km in altitude, during large eruptions. This relationship is complicated by the fact that the elevation between the volcano summit and the distance to the troposphere/stratosphere decreases with latitude. So, some smaller eruptions at higher latitudes can eject as much SO2 gas into the stratosphere as larger eruptions closer to the equator. Factors influencing the amounts of SO2 in the stratosphere were described and modeled by Bluth and others (1997). For eruptions in the last 25 years, El Chichon and Mount Pinatubo emitted the greatest amounts of SO2 into the stratosphere. El Chichon produced 7 Mt of SO2 and Mount Pinatubo produced 20 Mt. Both of these volcanoes are at low latitudes but they both had high eruption rates. The importance of latitude is obvious for four of the next five volcanoes that had a major influence on SO2 amounts in the stratosphere. Hudson, St. Helens, Alaid, and Redoubt are all at latitudes greater than 45 degrees, where the distance to the stratosphere is less. The eruption rate of Hudson was comparable to El Chichon and Mount Pinatubo. However, the eruption rates of St. Helens, Alaid, and Redoubt where an order of magnitude less. These volcanoes emitted 1, 1.1, and 0.2 Mt of SO2. The other eruption was at Ruiz, which had a high eruption rate, comparable to El Chichon and Mount Pinatubo, but is near the equator. Ruiz emitted 0.7 Mt of SO2. Bluth and others (1997) used the changes in aerosol optical depth as a measure of the impact of the eruptions. The impact of eruptions may not last very long. The aerosols in the stratosphere from mid-range eruptions (St. Helens, Alaid) settled back to the troposphere in about 5-8 months (Kent and McCormick, 1984). For large eruptions like El Chichon it takes about 12 months for SO2 levels in the stratosphere to return to pre-eruption levels. Pinto and others (1989) suggested that at high eruption rates aerosols tend to make larger particles, not greater numbers of same size aerosol particles. Larger particles have smaller optical depth per unit mass, relative to smaller particles, and settle out of the stratosphere faster. These self-limiting effects may restrict the total number of particles in the stratosphere and may moderate the impact of volcanic clouds (Rampino and Self, 1982; Pinto and others,1989). More complicated patterns of warming and cooling have been found on regional scales. Robock and Mao (1992) found warming over Eurasia and North America and cooling over the Middle East and northern Africa during the winters after the 12 largest volcanic eruptions from 1883-1992. For eruptions in the tropics the temperature changes were noted in the first winter after the eruption. For eruptions in the mid-latitudes changes were observed in the first or second winter after the eruption. For eruptions in high latitudes changes were observed in the second winter after the eruption. Robock and Mao (1992) proposed that heating of the tropical stratosphere by the volcanic aerosols led to an enhanced zonal winds. The zonal winds heated some areas while blocking of solar radiation cooled other areas. So2 is key to offset warming – studies prove Biello 11 — (David Biello, reporter for scientific american, science news agency, July 22, 2011, http://www.scientificamerican.com/article.cfm?id=stratospheric-pollution-helps-slow-global-warming) Despite significant pyrotechnics and air travel disruption last year, the Icelandic volcano Eyjafjallajokull simply didn't put that many aerosols into the stratosphere. In contrast, the eruption of Mount Pinatubo in 1991, put 10 cubic kilometers of ash, gas and other materials into the sky, and cooled the planet for a year. Now, research suggests that for the past decade, such stratospheric aerosols—injected into the atmosphere by either recent volcanic eruptions or human activities such as coal burning—are slowing down global warming.¶ "Aerosols acted to keep warming from being as big as it would have been," says atmospheric scientist John Daniel of the National Oceanic and Atmospheric Administration's (NOAA) Earth System Research Laboratory, who helped lead the research published online in Science on July 21. "It's still warming, it's just not warming as much as it would have been."¶ Essentially, sulfur dioxide gets emitted near the surface, either by a coal-fired power plant's smokestack or a volcano. If that SO2 makes it to the stratosphere—the middle layer of the atmosphere 10 kilometers up—it forms droplets of diluted sulfuric acid, known as aerosols. These aerosols reflect sunlight away from the planet, shading the surface and cooling temperatures. And some can persist for a few years, prolonging that cooling.¶ By analyzing satellite data and other measures, Daniel and his colleagues found that such aerosols have been on the rise in Earth's atmosphere in the past decade, nearly doubling in concentration. That concentration has reflected roughly 0.1 watts per meter squared of sunlight away from the planet, enough to offset roughly one-third of the 0.28 watts per meter squared of extra heat trapped by rising atmospheric concentrations of greenhouse gases such as carbon dioxide. The researchers calculate that the aerosols prevented 0.07 degrees Celsius of warming in average temperatures since 2000. Coal burning emits SO2 which cools the earth Biello (Environmental specialist staff writer for the Scientific American) 2011 (David, “Stratospheric Pollution Helps Slow Global Warming,” Energy & Sustainability, July 22, 2011, http://www.scientificamerican.com/article.cfm?id=stratospheric-pollution-helps-slow-global-warming) //CL Particles of sulfuric acid--injected by volcanoes or humans--have slowed the pace of climate change in the past decade Despite significant pyrotechnics and air travel disruption last year, the Icelandic volcano Eyjafjallajokull simply didn't put that many aerosols into the stratosphere. In contrast, the eruption of Mount Pinatubo in 1991, put 10 cubic kilometers of ash, gas and other materials into the sky, and cooled the planet for a year. Now, research suggests that for the past decade, such stratospheric aerosols—injected into the atmosphere by either recent volcanic eruptions or human activities such as coal burning—are slowing down global warming. "Aerosols acted to keep warming from being as big as it would have been," says atmospheric scientist John Daniel of the National Oceanic and Atmospheric Administration's (NOAA) Earth System Research Laboratory, who helped lead the research published online in Science on July 21. "It's still warming, it's just not warming as much as it would have been." Essentially, sulfur dioxide gets emitted near the surface, either by a coal-fired power plant's smokestack or a volcano. If that SO2 makes it to the stratosphere—the middle layer of the atmosphere 10 kilometers up—it forms droplets of diluted sulfuric acid, known as aerosols. These aerosols reflect sunlight away from the planet, shading the surface and cooling temperatures. And some can persist for a few years, prolonging that cooling. By analyzing satellite data and other measures, Daniel and his colleagues found that such aerosols have been on the rise in Earth's atmosphere in the past decade, nearly doubling in concentration. That concentration has reflected roughly 0.1 watts per meter squared of sunlight away from the planet, enough to offset roughly one-third of the 0.28 watts per meter squared of extra heat trapped by rising atmospheric concentrations of greenhouse gases such as carbon dioxide. The researchers calculate that the aerosols prevented 0.07 degrees Celsius of warming in average temperatures since 2000. The question is: why the increase in such aerosols? There have been plenty of smaller volcanic eruptions in recent years, such as the continuously erupting Soufriere Hills on Montserrat and Tavurvur on Papua New Guinea, which may have exploded enough SO2 into the atmosphere. And there has been plenty of coal burning in countries such as China, which now burns some 3 billion metric tons of the fuel rock per year, largely without the pollution controls that would scrub out the SO2, as is sometimes done in the U.S. In fact, a computer model study published July 5 in Proceedings of the National Academy of Sciences suggested that such SO2 pollution in China has cancelled out the warming effects of rising greenhouse gas concentrations globally since 1998. Determining whether humans or volcanoes explain more of the increase in stratospheric aerosols is the focus of ongoing research, says PhD candidate Ryan Neely of the University of Colorado, who contributed to the NOAA research. Combined with a decrease in atmospheric water vapor and a weaker sun due to the most recent solar cycle, the aerosol finding may explain why climate change has not been accelerating as fast as it did in the 1990s. The effect also illustrates one proposal for so-called geoengineering—the deliberate, large-scale manipulation of the planetary environment—that would use various means to create such sulfuric acid aerosols in the stratosphere to reflect sunlight and thereby hopefully forestall catastrophic climate change. But that points up another potential problem: if aerosol levels, whether natural or human-made, decline in the future, climate change could accelerate—and China is adding scrubbing technology to its coal-fired power plants to reduce SO2 emissions and thereby minimize acid rain. In effect, fixing acid rain could end up exacerbating global warming. China "could cause some decreases [in stratospheric aerosols] if that is the source," Neely says, adding that growing SO2 emissions from India could also increase cooling if humans are the dominant cause of injecting aerosols into the atmosphere. On the other hand, "if some volcanoes that are large enough go off and if they are the dominant cause [of increasing aerosols], then we will probably see some increases" in cooling. This is consistent with the conclusion of their studies Robock 8 (Alan Robock1, Luke Oman2, and Georgiy L. Stenchikov1 1Department of Environmental Sciences, Rutgers University, New Brunswick, New Jersey 2Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, Maryland March, 2008, http://www.see.ed.ac.uk/~shs/Climate%20change/Geo-politics/GeoengineeringJGR9inPress.pdf) Anthropogenic stratospheric aerosol production, so as to reduce solar insolation and cool Earth, has been suggested as an emergency response to geoengineer the planet in response to global warming. While volcanic eruptions have been suggested as innocuous examples of stratospheric aerosols cooling the planet, the volcano analog actually argues against geoengineering because of ozone depletion and regional hydrologic and temperature responses. To further investigate the climate response, here we simulate the climate response to both tropical and Arctic stratospheric injection of sulfate aerosol precursors using a comprehensive atmosphere-ocean general circulation model, the National Aeronautics and Space Administration Goddard Institute for Space Studies ModelE. We inject SO and the model converts it to sulfate aerosols, transports the aerosols and removes them through dry and wet deposition, and calculates the climate response to the radiative forcing from the aerosols. We conduct simulations of future climate with the Intergovernmental Panel on Climate Change A1B business-as-usual scenario both with and without geoengineering, and compare the results. We find that 2if there were a way to continuously inject SO2 into the lower stratosphere, it would produce global cooling. Tropical SO2 injection would produce sustained cooling over most of the world, with more cooling over continents. Arctic SO2 injection would not just cool the Arctic. Both tropical and Arctic SO2 injection would disrupt the Asian and African summer monsoons, reducing precipitation to the food supply for billions of people. These regional climate anomalies are but one of many reasons that argue against the implementation of this kind of geoengineering. 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. 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