Science.gov

Sample records for geoengineering symposium friday

  1. Geoengineering on exoplanets

    NASA Astrophysics Data System (ADS)

    Lockley, Andrew

    2015-04-01

    Solar radiation management (SRM) geoengineering can be used to deliberately alter the Earth's radiation budget, by reflecting sunlight to space. SRM has been suggested as a response to Anthropogenic Global Warming (AGW), to partly or fully balance radiative forcing from AGW [1]. Approximately 22% of sun-like stars have Earth-like exoplanets[2]. Advanced civilisations may exist on these, and may use geoengineering for positive or negative radiative forcing. Additionally, terraforming projects [e.g. 3], may be used to expand alien habitable territory, or for resource management or military operations on non-home planets. Potential observations of alien geoengineering and terraforming may enable detection of technologically advanced alien civilisations, and may help identify widely-used and stable geoengineering technologies. This knowledge may assist the development of safe and stable geoengineering methods for Earth. The potential risks and benefits of possible alien detection of Earth-bound geoengineering schemes must be considered before deployment of terrestrial geoengineering schemes.

  2. Stratospheric aerosol geoengineering

    SciTech Connect

    Robock, Alan

    2015-03-30

    The Geoengineering Model Intercomparison Project, conducting climate model experiments with standard stratospheric aerosol injection scenarios, has found that insolation reduction could keep the global average temperature constant, but global average precipitation would reduce, particularly in summer monsoon regions around the world. Temperature changes would also not be uniform; the tropics would cool, but high latitudes would warm, with continuing, but reduced sea ice and ice sheet melting. Temperature extremes would still increase, but not as much as without geoengineering. If geoengineering were halted all at once, there would be rapid temperature and precipitation increases at 5–10 times the rates from gradual global warming. The prospect of geoengineering working may reduce the current drive toward reducing greenhouse gas emissions, and there are concerns about commercial or military control. Because geoengineering cannot safely address climate change, global efforts to reduce greenhouse gas emissions and to adapt are crucial to address anthropogenic global warming.

  3. Geoengineering as Collective Experimentation.

    PubMed

    Stilgoe, Jack

    2016-06-01

    Geoengineering is defined as the 'deliberate and large-scale intervention in the Earth's climatic system with the aim of reducing global warming'. The technological proposals for doing this are highly speculative. Research is at an early stage, but there is a strong consensus that technologies would, if realisable, have profound and surprising ramifications. Geoengineering would seem to be an archetype of technology as social experiment, blurring lines that separate research from deployment and scientific knowledge from technological artefacts. Looking into the experimental systems of geoengineering, we can see the negotiation of what is known and unknown. The paper argues that, in renegotiating such systems, we can approach a new mode of governance-collective experimentation. This has important ramifications not just for how we imagine future geoengineering technologies, but also for how we govern geoengineering experiments currently under discussion. PMID:25862639

  4. Ranking geo-engineering schemes

    NASA Astrophysics Data System (ADS)

    Boyd, Philip W.

    2008-11-01

    Geo-engineering proposals for mitigating climate change continue to proliferate without being tested. It is time to select and assess the most promising ideas according to efficacy, cost, all aspects of risk and, importantly, their rate of mitigation.

  5. Geoengineering the Earth's Climate

    SciTech Connect

    Google Tech Talks

    2008-01-08

    Emergency preparedness is generally considered to be a good thing, yet there is no plan regarding what we might do should we be faced with a climate emergency. Such an emergency could take the form of a rapid shift in precipitation patterns, a collapse of the great ice sheets, the imminent triggering of strong climate system feedbacks, or perhaps the loss of valuable ecosystems. Over the past decade, we have used climate models to investigate the potential to reverse some of the effects of greenhouse gases in the atmosphere by deflecting some incoming sunlight back to space. This would probably be most cost-effectively achieved with the placement of small particles in or above the stratosphere. Our model simulations indicate that such geoengineering approaches could potentially bring our climate closer to the state is was in prior to the introduction of greenhouse gases. This talk will present much of what is known about such geoengineering approaches, and raise a range of issues likely to stimulate lively discussion. Speaker: Ken Caldeira Ken Caldeira is a scientist at the Carnegie Institution Department of Global Ecology and a Professor (by courtesy) at the Stanford University Department of Environmental and Earth System Sciences. Previously, he worked for 12 years in the Energy and Environment Directorate at the Lawrence Livermore National Laboratory (Department of Energy). His research interests include the numerical simulation of Earth's climate, carbon, and biogeochemistry; ocean acidification; climate emergency response systems; evaluating approaches to supplying environmentally-friendly energy services; ocean carbon sequestration; long-term evolution of climate and geochemical cycles; and marine biogeochemical cycles. Caldeira has a B.A. in Philosophy from Rutgers College and an M.S. and Ph.D. in Atmospheric Sciences from New York University.

  6. Geoengineering the Earth's Climate

    ScienceCinema

    Google Tech Talks

    2009-09-01

    Emergency preparedness is generally considered to be a good thing, yet there is no plan regarding what we might do should we be faced with a climate emergency. Such an emergency could take the form of a rapid shift in precipitation patterns, a collapse of the great ice sheets, the imminent triggering of strong climate system feedbacks, or perhaps the loss of valuable ecosystems. Over the past decade, we have used climate models to investigate the potential to reverse some of the effects of greenhouse gases in the atmosphere by deflecting some incoming sunlight back to space. This would probably be most cost-effectively achieved with the placement of small particles in or above the stratosphere. Our model simulations indicate that such geoengineering approaches could potentially bring our climate closer to the state is was in prior to the introduction of greenhouse gases. This talk will present much of what is known about such geoengineering approaches, and raise a range of issues likely to stimulate lively discussion. Speaker: Ken Caldeira Ken Caldeira is a scientist at the Carnegie Institution Department of Global Ecology and a Professor (by courtesy) at the Stanford University Department of Environmental and Earth System Sciences. Previously, he worked for 12 years in the Energy and Environment Directorate at the Lawrence Livermore National Laboratory (Department of Energy). His research interests include the numerical simulation of Earth's climate, carbon, and biogeochemistry; ocean acidification; climate emergency response systems; evaluating approaches to supplying environmentally-friendly energy services; ocean carbon sequestration; long-term evolution of climate and geochemical cycles; and marine biogeochemical cycles. Caldeira has a B.A. in Philosophy from Rutgers College and an M.S. and Ph.D. in Atmospheric Sciences from New York University.

  7. Atlantic hurricane response to geoengineering

    NASA Astrophysics Data System (ADS)

    Moore, John; Grinsted, Aslak; Ji, Duoying; Yu, Xiaoyong; Guo, Xiaoran

    2015-04-01

    Devastating Atlantic hurricanes are relatively rare events. However their intensity and frequency in a warming world may rapidly increase - perhaps by a factor of 5 for a 2°C mean global warming. Geoengineering by sulphate aerosol injection preferentially cools the tropics relative to the polar regions, including the hurricane main development region in the Atlantic, suggesting that geoengineering may be an effective method of controlling hurricanes. We examine this hypothesis using 6 Earth System Model simulations of climate under the GeoMIP G3 and G4 schemes that use aerosols to reduce the radiative forcing under the RCP4.5 scenario. We find that although temperatures are ameliorated by geoengineering, the numbers of storm surge events as big as that caused the 2005 Katrina hurricane are only slightly reduced compared with no geoengineering. As higher levels of sulphate aerosol injection produce diminishing returns in terms of cooling, but cause undesirable effects in various regions, it seems that stratospheric aerosol geoengineering is not an effective method of controlling hurricane damage.

  8. In Brief: Geoengineering draft statement

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2009-04-01

    The American Meteorological Society (AMS) has prepared a draft policy statement on geoengineering the climate system, which the AMS Council is considering for approval. The statement notes, “Geoengineering will not substitute for either aggressive mitigation or proactive adaptation. It could contribute to a comprehensive risk management strategy to slow climate change and alleviate its negative impacts, but the potential for adverse and unintended consequences implies a need for adequate research, appropriate regulation, and transparent consideration.” The statement, if adopted, indicates that AMS recommends enhanced research on the scientific and technological potential for geoengineering the climate system; additional study of the historical, ethical, legal, political, and societal aspects of the geoengineering issues; and the development and analysis of policy options to promote transparency and international cooperation in exploring geoengineering options along with restrictions on reckless efforts to manipulate the climate system. AMS is accepting comments on the draft statement until 23 April. For more information, visit http://ametsoc.org/policy/draftstatements/index.html#draft.

  9. Geoengineering treatment of methane

    NASA Astrophysics Data System (ADS)

    Lockley, Andrew; Gardian, Alan

    2010-05-01

    Methane is a significant GHG, and substantial reservoirs are vulnerable to instability due to AGW. Excursions, from permafrost and clathrates especially, act a positive feedback to AGW. Existing concentrations of well-mixed atmospheric methane substantially exceed pre-industrial levels. Various geoengineering methods are herein proposed for containment of methane, and/or accelerated oxidation to CO2 (a gas with a lower GWP over all timescales). A basic qualitative analysis of each technique is undertaken, to direct further study. Consideration is also given to the potential capacity of each technique to treat the total likely excursions of methane expected as a result of AGW. Proposed techniques: Section 0 SRM (comparison option) Section 1 Pre-emptive treatment of methane reservoirs Soil heating (polytunnels, heat pumps); Soil aeration; Mining of clathrates; Burning of clathrates Section 2 Remediation of aquatic methane excursions Lake sealing; Mixing of aquatic strata; Bubble capture; Lake aeration; Biological oxidation in aquatic environments Section 3 Remediation of concentrated atmospheric methane Regenerative thermal oxidation; Electrical ignition; Thermal ignition; Using incendiary munitions Section 4 Remediation of diffuse atmospheric methane Thermal oxidation by concentrated solar power; Compression ignition; Chemical degradation Assessment criteria: Infrastructure/implementation cost; Energy cost; Expected efficacy; Complexity/development path; Environmental impacts; Potential for CCS

  10. Fractals for Geoengineering

    NASA Astrophysics Data System (ADS)

    Oleshko, Klaudia; de Jesús Correa López, María; Romero, Alejandro; Ramírez, Victor; Pérez, Olga

    2016-04-01

    The effectiveness of fractal toolbox to capture the scaling or fractal probability distribution, and simply fractal statistics of main hydrocarbon reservoir attributes, was highlighted by Mandelbrot (1995) and confirmed by several researchers (Zhao et al., 2015). Notwithstanding, after more than twenty years, it's still common the opinion that fractals are not useful for the petroleum engineers and especially for Geoengineering (Corbett, 2012). In spite of this negative background, we have successfully applied the fractal and multifractal techniques to our project entitled "Petroleum Reservoir as a Fractal Reactor" (2013 up to now). The distinguishable feature of Fractal Reservoir is the irregular shapes and rough pore/solid distributions (Siler, 2007), observed across a broad range of scales (from SEM to seismic). At the beginning, we have accomplished the detailed analysis of Nelson and Kibler (2003) Catalog of Porosity and Permeability, created for the core plugs of siliciclastic rocks (around ten thousand data were compared). We enriched this Catalog by more than two thousand data extracted from the last ten years publications on PoroPerm (Corbett, 2012) in carbonates deposits, as well as by our own data from one of the PEMEX, Mexico, oil fields. The strong power law scaling behavior was documented for the major part of these data from the geological deposits of contrasting genesis. Based on these results and taking into account the basic principles and models of the Physics of Fractals, introduced by Per Back and Kan Chen (1989), we have developed new software (Muukíl Kaab), useful to process the multiscale geological and geophysical information and to integrate the static geological and petrophysical reservoir models to dynamic ones. The new type of fractal numerical model with dynamical power law relations among the shapes and sizes of mesh' cells was designed and calibrated in the studied area. The statistically sound power law relations were established

  11. Fractals for Geoengineering

    NASA Astrophysics Data System (ADS)

    Oleshko, Klaudia; de Jesús Correa López, María; Romero, Alejandro; Ramírez, Victor; Pérez, Olga

    2016-04-01

    The effectiveness of fractal toolbox to capture the scaling or fractal probability distribution, and simply fractal statistics of main hydrocarbon reservoir attributes, was highlighted by Mandelbrot (1995) and confirmed by several researchers (Zhao et al., 2015). Notwithstanding, after more than twenty years, i&tacute;s still common the opinion that fractals are not useful for the petroleum engineers and especially for Geoengineering (Corbett, 2012). In spite of this negative background, we have successfully applied the fractal and multifractal techniques to our project entitled "Petroleum Reservoir as a Fractal Reactor" (2013 up to now). The distinguishable feature of Fractal Reservoir is the irregular shapes and rough pore/solid distributions (Siler, 2007), observed across a broad range of scales (from SEM to seismic). At the beginning, we have accomplished the detailed analysis of Nelson and Kibler (2003) Catalog of Porosity and Permeability, created for the core plugs of siliciclastic rocks (around ten thousand data were compared). We enriched this Catalog by more than two thousand data extracted from the last ten years publications on PoroPerm (Corbett, 2012) in carbonates deposits, as well as by our own data from one of the PEMEX, Mexico, oil fields. The strong power law scaling behavior was documented for the major part of these data from the geological deposits of contrasting genesis. Based on these results and taking into account the basic principles and models of the Physics of Fractals, introduced by Per Back and Kan Chen (1989), we have developed new software (Muuḱil Kaab), useful to process the multiscale geological and geophysical information and to integrate the static geological and petrophysical reservoiŕ models to dynamic ones. The new type of fractal numerical model with dynamical power law relations among the shapes and sizes of mes&hacute; cells was designed and calibrated in the studied area. The statistically sound power law relations were

  12. On solar geoengineering and climate uncertainty

    SciTech Connect

    MacMartin, Douglas; Kravitz, Benjamin S.; Rasch, Philip J.

    2015-09-03

    Uncertainty in the climate system response has been raised as a concern regarding solar geoengineering. Here we show that model projections of regional climate change outcomes may have greater agreement under solar geoengineering than with CO2 alone. We explore the effects of geoengineering on one source of climate system uncertainty by evaluating the inter-model spread across 12 climate models participating in the Geoengineering Model Intercomparison project (GeoMIP). The model spread in regional temperature and precipitation changes is reduced with CO2 and a solar reduction, in comparison to the case with increased CO2 alone. That is, the intermodel spread in predictions of climate change and the model spread in the response to solar geoengineering are not additive but rather partially cancel. Furthermore, differences in efficacy explain most of the differences between models in their temperature response to an increase in CO2 that is offset by a solar reduction. These conclusions are important for clarifying geoengineering risks.

  13. Future Directions in Simulating Solar Geoengineering

    SciTech Connect

    Kravitz, Benjamin S.; Robock, Alan; Boucher, Olivier

    2014-08-05

    Solar geoengineering is a proposed set of technologies to temporarily alleviate some of the consequences of anthropogenic greenhouse gas emissions. The Geoengineering Model Intercomparison Project (GeoMIP) created a framework of geoengineering simulations in climate models that have been performed by modeling centers throughout the world (B. Kravitz et al., The Geoengineering Model Intercomparison Project (GeoMIP), Atmospheric Science Letters, 12(2), 162-167, doi:10.1002/asl.316, 2011). These experiments use state-of-the-art climate models to simulate solar geoengineering via uniform solar reduction, creation of stratospheric sulfate aerosol layers, or injecting sea spray into the marine boundary layer. GeoMIP has been quite successful in its mission of revealing robust features and key uncertainties of the modeled effects of solar geoengineering.

  14. A Knack for Numbers: Paquita Friday

    ERIC Educational Resources Information Center

    Yates, Eleanor Lee

    2005-01-01

    Back in middle school Dr. Paquita Friday began helping keep books at her grandmother's pharmacy during inventory. It was no chore, she recalls. It was fun. By then, of course, she already knew she had a knack for numbers. Today Friday is gaining recognition for her research in accounting stock market disclosures and winning awards for her teaching…

  15. Lights, Camera, Action... It's "Science Friday"!

    ERIC Educational Resources Information Center

    Tugurian, Linda; Blanchard, Margaret R.

    2010-01-01

    "Science Friday's" motto "Making Science User-Friendly" was the authors' inspiration, as was its format for a segment on the morning broadcast at Forest View Elementary School. Patterned after National Public Radio's "Science Friday," this special feature was designed to provide an opportunity for budding scientists to communicate their…

  16. Effects of sea spray geoengineering

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-03-01

    Anthropogenic climate warming is leading to consideration of options for geoengineering to offset rising carbon dioxide levels. One potential technique involves injecting artificial sea spray into the atmosphere. The sea salt particles would affect Earth's radiation budget directly, by scattering incoming solar radiation, and indirectly, by acting as cloud condensation nuclei, which could lead to whiter clouds that reflect more radiation. However, the potential effects of this method, especially the direct effects, are not fully known. Partanen et al. studied the effects of artificial sea spray using climate model simulations. They found that outside of the most heavily clouded regions the direct effect of scattering of radiation was an important part of the total effect. They also examined the effect of particle size and found that decreasing the size of injected particles could improve the efficiency of the geoengineering technique.

  17. Geo-Engineering through Internet Informatics (GEMINI)

    SciTech Connect

    Doveton, John H.; Watney, W. Lynn

    2003-03-06

    The program, for development and methodologies, was a 3-year interdisciplinary effort to develop an interactive, integrated Internet Website named GEMINI (Geo-Engineering Modeling through Internet Informatics) that would build real-time geo-engineering reservoir models for the Internet using the latest technology in Web applications.

  18. Geoengineering: An Idea Whose Time Has Come?

    PubMed Central

    Resnik, David B.; Vallero, Daniel A.

    2013-01-01

    Some engineers and scientists recently have suggested that it would be prudent to consider engaging in geoengineering to mitigate global warming. Geoengineering differs from other methods for mitigating global warming because it involves a deliberate effort to affect the climate at a global scale. Although geoengineering is not a new idea, it has taken on added significance as a result of difficulties with implementing other proposals to mitigate climate change. While proponents of geoengineering admit that it can have significant risks for the environment and public health, many maintain that it is worth pursuing, given the failure of other means of mitigating global warming. Some environmental groups have voiced strong opposition to all forms of geoengineering. In this article, we examine arguments for and against geoengineering and discuss some policy options. We argue that specific geoengineering proposals should not be implemented until there is good evidence concerning their safety, efficacy, and feasibility, as well as a plan for oversight. International cooperation and public input should also be sought. Other methods for mitigating global warming should be aggressively pursued while geoengineering is under consideration. The promise of an engineering solution to global warming should not be used as an excuse to abandon or cut back current, climate mitigation efforts. PMID:23502911

  19. On solar geoengineering and climate uncertainty

    NASA Astrophysics Data System (ADS)

    MacMartin, Douglas G.; Kravitz, Ben; Rasch, Philip J.

    2015-09-01

    Uncertain climate system response has been raised as a concern regarding solar geoengineering. We explore the effects of geoengineering on one source of climate system uncertainty by evaluating the intermodel spread across 12 climate models participating in the Geoengineering Model Intercomparison project. The model spread in simulations of climate change and the model spread in the response to solar geoengineering are not additive but rather partially cancel. That is, the model spread in regional temperature and precipitation changes is reduced with CO2 and a solar reduction, in comparison to the case with increased CO2 alone. Furthermore, differences between models in their efficacy (the relative global mean temperature effect of solar versus CO2 radiative forcing) explain most of the regional differences between models in their response to an increased CO2 concentration that is offset by a solar reduction. These conclusions are important for clarifying geoengineering risks regarding uncertainty.

  20. Exploring early public responses to geoengineering.

    PubMed

    Pidgeon, Nick; Corner, Adam; Parkhill, Karen; Spence, Alexa; Butler, Catherine; Poortinga, Wouter

    2012-09-13

    Proposals for geoengineering the Earth's climate are prime examples of emerging or 'upstream' technologies, because many aspects of their effectiveness, cost and risks are yet to be researched, and in many cases are highly uncertain. This paper contributes to the emerging debate about the social acceptability of geoengineering technologies by presenting preliminary evidence on public responses to geoengineering from two of the very first UK studies of public perceptions and responses. The discussion draws upon two datasets: qualitative data (from an interview study conducted in 42 households in 2009), and quantitative data (from a subsequent nationwide survey (n=1822) of British public opinion). Unsurprisingly, baseline awareness of geoengineering was extremely low in both cases. The data from the survey indicate that, when briefly explained to people, carbon dioxide removal approaches were preferred to solar radiation management, while significant positive correlations were also found between concern about climate change and support for different geoengineering approaches. We discuss some of the wider considerations that are likely to shape public perceptions of geoengineering as it enters the media and public sphere, and conclude that, aside from technical considerations, public perceptions are likely to prove a key element influencing the debate over questions of the acceptability of geoengineering proposals. PMID:22869796

  1. The risks and efficacy of solar geoengineering

    SciTech Connect

    Keith, David

    2012-12-05

    Solar geoengineering may enable a significant reduction in climate risks by partially offsetting climate change due to increasing greenhouse gases, however this emerging technology entails novel risks and uncertainties along with serious challenges to global governance. I will attempt a rough summary of the physics of solar geoengineering and present recent findings regarding (a) the climate's response to radiative forcing by stratospheric aerosols, (b) methods of producing appropriate aerosol distributions, and (c) risks. In closing I will discuss the trade-off between solar geoengineering, emissions reductions and adaptation in climate policy.

  2. Global change - Geoengineering and space exploration

    NASA Technical Reports Server (NTRS)

    Jenkins, Lyle M.

    1992-01-01

    Geoengineering options and alternatives are proposed for mitigating the effects of global climate change and depletion of the ozone layer. Geoengineering options were discussed by the National Academy of Science Panel on the Policy Implications of Greenhouse Warming. Several of the ideas conveyed in their published report are space-based or depend on space systems for implementation. Among the geoengineering options using space that are discussed include the use of space power systems as an alternative to fossil fuels for generating electricity, the use of lunar He-3 to aid in the development of fusion energy, and the establishment of a lunar power system for solar energy conversion and electric power beaming back to earth. Other geoengineering options are discussed. They include the space-based modulation of hurricane forces and two space-based approaches in dealing with ozone layer depletion. The engineering challenges and policy implementation issues are discussed for these geongineering options.

  3. Climatic effects of surface albedo geoengineering

    NASA Astrophysics Data System (ADS)

    Irvine, Peter J.; Ridgwell, Andy; Lunt, Daniel J.

    2011-12-01

    Various surface albedo modification geoengineering schemes such as those involving desert, urban, or agricultural areas have been proposed as potential strategies for helping counteract the warming caused by greenhouse gas emissions. However, such schemes tend to be inherently limited in their potential and would create a much more heterogeneous radiative forcing than propositions for space-based "reflectors" and enhanced stratospheric aerosol concentrations. Here we present results of a series of atmosphere-ocean general circulation model (GCM) simulations to compare three surface albedo geoengineering proposals: urban, cropland, and desert albedo enhancement. We find that the cooling effect of surface albedo modification is strongly seasonal and mostly confined to the areas of application. For urban and cropland geoengineering, the global effects are minor but, because of being colocated with areas of human activity, they may provide some regional benefits. Global desert geoengineering, which is associated with significant global-scale changes in circulation and the hydrological cycle, causes a smaller reduction in global precipitation per degree of cooling than sunshade geoengineering, 1.1% K-1 and 2.0% K-1 respectively, but a far greater reduction in the precipitation over land, 3.9% K-1 compared with 1.0% K-1. Desert geoengineering also causes large regional-scale changes in precipitation with a large reduction in the intensity of the Indian and African monsoons in particular. None of the schemes studied reverse the climate changes associated with a doubling of CO2, with desert geoengineering profoundly altering the climate and with urban and cropland geoengineering providing only some regional amelioration at most.

  4. Geoengineering the climate: an overview and update.

    PubMed

    Shepherd, J G

    2012-09-13

    The climate change that we are experiencing now is caused by an increase in greenhouse gases due to human activities, including burning fossil fuels, agriculture and deforestation. There is now widespread belief that a global warming of greater than 2(°)C above pre-industrial levels would be dangerous and should therefore be avoided. However, despite growing concerns over climate change and numerous international attempts to agree on reductions of global CO(2) emissions, these have continued to climb. This has led some commentators to suggest more radical 'geoengineering' alternatives to conventional mitigation by reductions in CO(2) emissions. Geoengineering is deliberate intervention in the climate system to counteract man-made global warming. There are two main classes of geoengineering: direct carbon dioxide removal and solar radiation management that aims to cool the planet by reflecting more sunlight back to space. The findings of the review of geoengineering carried out by the UK Royal Society in 2009 are summarized here, including the climate effects, costs, risks and research and governance needs for various approaches. The possible role of geoengineering in a portfolio of responses to climate change is discussed, and various recent initiatives to establish good governance of research activity are reviewed. Key findings include the following.- Geoengineering is not a magic bullet and not an alternative to emissions reductions. - Cutting global greenhouse gas emissions must remain our highest priority. (i) But this is proving to be difficult, and geoengineering may be useful to support it. - Geoengineering is very likely to be technically possible. (i) However, there are major uncertainties and potential risks concerning effectiveness, costs and social and environmental impacts. - Much more research is needed, as well as public engagement and a system of regulation (for both deployment and for possible large-scale field tests). - The acceptability of

  5. Geoengineering and the Problem of Harm

    NASA Astrophysics Data System (ADS)

    Bunzl, M.

    2008-12-01

    Suppose geoengineering "works" and that there are no competing antagonistic interventions. Even on this rosy scenario, it is extremely unlikely that it will "work" for everyone since (as Schneider pointed out many years ago) there is no reason to think the effects of geoengineering will offset the effects of global warming locally. But as Robock et al have argued (Robock, Alan, Luke Oman, and Georgiy Stenchikov, 2008: Regional climate responses to geoengineering with tropical and arctic SO2 injections. J. Geophys. Res., in press), things may even worse than that. Suppose in some places (e.g. India), climate change + geoengineering leaves you worse off (hotter and drier) than climate change alone. Might it nonetheless be fair to proceed on the basis of the numbers - that is if many more would benefit than those who would not? I consider under what circumstances we may "let the numbers count", and where it is wrong to do so, irrespective of the numbers. I argue that the case of geoengineering is one in which we may let the numbers count, but only under conditions that are extremely difficult to satisfy.

  6. Geoengineering as a design problem

    NASA Astrophysics Data System (ADS)

    Kravitz, Ben; MacMartin, Douglas G.; Wang, Hailong; Rasch, Philip J.

    2016-05-01

    Understanding the climate impacts of solar geoengineering is essential for evaluating its benefits and risks. Most previous simulations have prescribed a particular strategy and evaluated its modeled effects. Here we turn this approach around by first choosing example climate objectives and then designing a strategy to meet those objectives in climate models. There are four essential criteria for designing a strategy: (i) an explicit specification of the objectives, (ii) defining what climate forcing agents to modify so the objectives are met, (iii) a method for managing uncertainties, and (iv) independent verification of the strategy in an evaluation model. We demonstrate this design perspective through two multi-objective examples. First, changes in Arctic temperature and the position of tropical precipitation due to CO2 increases are offset by adjusting high-latitude insolation in each hemisphere independently. Second, three different latitude-dependent patterns of insolation are modified to offset CO2-induced changes in global mean temperature, interhemispheric temperature asymmetry, and the Equator-to-pole temperature gradient. In both examples, the "design" and "evaluation" models are state-of-the-art fully coupled atmosphere-ocean general circulation models.

  7. Atlantic hurricane surge response to geoengineering

    PubMed Central

    Moore, John C.; Grinsted, Aslak; Guo, Xiaoran; Yu, Xiaoyong; Jevrejeva, Svetlana; Rinke, Annette; Cui, Xuefeng; Kravitz, Ben; Lenton, Andrew; Watanabe, Shingo; Ji, Duoying

    2015-01-01

    Devastating floods due to Atlantic hurricanes are relatively rare events. However, the frequency of the most intense storms is likely to increase with rises in sea surface temperatures. Geoengineering by stratospheric sulfate aerosol injection cools the tropics relative to the polar regions, including the hurricane Main Development Region in the Atlantic, suggesting that geoengineering may mitigate hurricanes. We examine this hypothesis using eight earth system model simulations of climate under the Geoengineering Model Intercomparison Project (GeoMIP) G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the Representative Concentration Pathway (RCP) 4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those temperature increases in the RCP4.5. However, sulfate injection would have to double (to nearly 10 teragrams of SO2 per year) between 2020 and 2070 to balance the RCP4.5, approximately the equivalent of a 1991 Pinatubo eruption every 2 y, with consequent implications for stratospheric ozone. We project changes in storm frequencies using a temperature-dependent generalized extreme value statistical model calibrated by historical storm surges and observed temperatures since 1923. The number of storm surge events as big as the one caused by the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this reduction is only marginally statistically significant. Nevertheless, when sea level rise differences in 2070 between the RCP4.5 and geoengineering are factored into coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5-y events and about halved for 50-y surges. PMID:26504210

  8. Atlantic hurricane surge response to geoengineering.

    PubMed

    Moore, John C; Grinsted, Aslak; Guo, Xiaoran; Yu, Xiaoyong; Jevrejeva, Svetlana; Rinke, Annette; Cui, Xuefeng; Kravitz, Ben; Lenton, Andrew; Watanabe, Shingo; Ji, Duoying

    2015-11-10

    Devastating floods due to Atlantic hurricanes are relatively rare events. However, the frequency of the most intense storms is likely to increase with rises in sea surface temperatures. Geoengineering by stratospheric sulfate aerosol injection cools the tropics relative to the polar regions, including the hurricane Main Development Region in the Atlantic, suggesting that geoengineering may mitigate hurricanes. We examine this hypothesis using eight earth system model simulations of climate under the Geoengineering Model Intercomparison Project (GeoMIP) G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the Representative Concentration Pathway (RCP) 4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those temperature increases in the RCP4.5. However, sulfate injection would have to double (to nearly 10 teragrams of SO2 per year) between 2020 and 2070 to balance the RCP4.5, approximately the equivalent of a 1991 Pinatubo eruption every 2 y, with consequent implications for stratospheric ozone. We project changes in storm frequencies using a temperature-dependent generalized extreme value statistical model calibrated by historical storm surges and observed temperatures since 1923. The number of storm surge events as big as the one caused by the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this reduction is only marginally statistically significant. Nevertheless, when sea level rise differences in 2070 between the RCP4.5 and geoengineering are factored into coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5-y events and about halved for 50-y surges. PMID:26504210

  9. Climate impacts of geoengineering marine stratocumulus clouds

    NASA Astrophysics Data System (ADS)

    Jones, Andy; Haywood, Jim; Boucher, Olivier

    2009-05-01

    Theoretical potential geoengineering solutions to the global warming problem have recently been proposed. Here, we present an idealized study of the climate response to deliberately seeding large-scale stratocumulus cloud decks in the North Pacific, South Pacific, and South Atlantic, thereby inducing cooling via aerosol indirect effects. Atmosphere-only, atmosphere/mixed-layer ocean, and fully coupled atmosphere/ocean versions of the Met Office Hadley Centre model are used to investigate the radiative forcing, climate efficacy, and regional response of temperature, precipitation, and net primary productivity to such geoengineering. The radiative forcing simulations indicate that, for our parameterization of aerosol indirect effects, up to 35% of the radiative forcing due to current levels of greenhouse gases could be offset by stratocumulus modification. Equilibrium simulations with the atmosphere/mixed-layer ocean model, wherein each of the three stratocumulus sheets is modified in turn, reveal that the most efficient cooling per unit radiative forcing occurs when the South Pacific stratocumulus sheet is modified. Transient coupled model simulations suggest that geoengineering all three stratocumulus areas delays the simulated global warming by about 25 years. These simulations also indicate that, while some areas experience increases in precipitation and net primary productivity, sharp decreases are simulated in South America, with particularly detrimental impacts on the Amazon rain forest. These results show that, while some areas benefit from geoengineering, there are significant areas where the response could be very detrimental with implications for the practical applicability of such a scheme.

  10. Stratospheric sulfate geoengineering impacts on global agriculture

    NASA Astrophysics Data System (ADS)

    Xia, L.; Robock, A.; Lawrence, P.; Lombardozzi, D.

    2015-12-01

    Stratospheric sulfate geoengineering has been proposed to reduce the impacts of anthropogenic climate change. If it is ever used, it would change agricultural production, and so is one of the future climate scenarios for the third phase of the Global Gridded Crop Model Intercomparison. As an example of those impacts, we use the Community Land Model (CLM-crop 4.5) to simulate how climate changes from the G4 geoengineering scenario from the Geoengineering Modeling Intercomparison Project. The G4 geoengineering scenario specifies, in combination with RCP4.5 forcing, starting in 2020 daily injections of a constant amount of SO2 at a rate of 5 Tg SO2 per year at one point on the Equator into the lower stratosphere. Eight climate modeling groups have completed G4 simulations. We use the crop model to simulate the impacts of climate change (temperature, precipitation, and solar radiation) on the global agriculture system for five crops - rice, maize, soybeans, cotton, and sugarcane. In general, without irrigation, compared with the reference run (RCP4.5), global production of cotton, rice and sugarcane would increase significantly due to the cooling effect. Maize and soybeans show different regional responses. In tropical regions, maize and soybean have a higher yield in G4 compared with RCP4.5, while in the temperate regions they have a lower yield under a geoengineered climate. Impacts on specific countries in terms of different crop production depend on their locations. For example, the United States and Argentina show soybean production reduction of about 15% under G4 compared to RCP4.5, while Brazil increases soybean production by about 10%.

  11. Atlantic hurricane surge response to geoengineering

    SciTech Connect

    Moore, John C.; Grinsted, Aslak; Guo, Xiaoran; Yu, Xiaoyong; Jevrejeva, Svetlana; Rinke, Annette; Cui, Xuefeng; Kravitz, Ben; Lenton, Andrew; Watanabe, Shingo; Ji, Duoying

    2015-10-26

    Devastating Atlantic hurricanes are relatively rare events. However their intensity and frequency in a warming world may rapidly increase by a factor of 2-7 for each degree of increase in mean global temperature. Geoengineering by stratospheric sulphate aerosol injection cools the tropics relative to the polar regions, including the hurricane main development region in the Atlantic, suggesting that geoengineering may be an effective method of controlling hurricanes. We examine this hypothesis using 8 Earth System Model simulations of climate under the GeoMIP G3 and G4 schemes that use stratospheric aerosols to reduce the radiative forcing under the RCP4.5 scenario. Global mean temperature increases are greatly ameliorated by geoengineering, and tropical temperature increases are at most half of those in RCP4.5, but sulphate injection would have to double between 2020 and 2070 to balance RCP 4.5 to nearly 10 Tg SO2 yr-1, with consequent implications for damage to stratospheric ozone. We project changes in storm frequencies using a temperature-dependent Generalized Extreme Value statistical model calibrated by historical storm surges from 1923 and observed temperatures. The numbers of storm surge events as big as the one that caused the 2005 Katrina hurricane are reduced by about 50% compared with no geoengineering, but this is only marginally statistically significant. However, when sea level rise differences at 2070 between RCP4.5 and geoengineering are factored in to coastal flood risk, we find that expected flood levels are reduced by about 40 cm for 5 year events and perhaps halved for 50 year surges.

  12. Geoengineering to Avoid Overshoot: An Uncertainty Analysis

    NASA Astrophysics Data System (ADS)

    Tanaka, K.

    2009-04-01

    Geoengineering (or climate engineering) using stratospheric sulfur injections (Crutzen, 2006) has been called for research in case of an urgent need for stopping global warming when other mitigation efforts were exhausted. Although there are a number of concerns over this idea (e.g. Robock, 2008), it is still useful to consider geoengineering as a possible method to limit warming caused by overshoot. Overshoot is a feature accompanied by low stabilizations scenarios aiming for a stringent target (Rao et al., 2008) in which total radiative forcing temporarily exceeds the target before reaching there. Scenarios achieving a 50% emission reduction by 2050 produces overshoot. Overshoot could cause sustained warming for decades due to the inertia of the climate system. If stratospheric sulfur injections were to be used as a "last resort" to avoid overshoot, what would be the suitable start-year and injection profile of such an intervention? Wigley (2006) examined climate response to combined mitigation/geoengineering scenarios with the intent to avert overshoot. Wigley's analysis demonstrated a basic potential of such a combined mitigation/geoengineering approach to avoid temperature overshoot - however it considered only simplistic sulfur injection profiles (all started in 2010), just one mitigation scenario, and did not examine the sensitivity of the climate response to any underlying uncertainties. This study builds upon Wigley's premise of the combined mitigation/geoengineering approach and brings associated uncertainty into the analysis. First, this study addresses the question as to how much geoengineering intervention would be needed to avoid overshoot by considering associated uncertainty? Then, would a geoengineering intervention of such a magnitude including uncertainty be permissible in considering all the other side effects? This study begins from the supposition that geoengineering could be employed to cap warming at 2.0°C since preindustrial. A few

  13. Scientists Debate Geoengineering at European Geosciences Union Meeting

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2014-05-01

    Recent reports by the Intergovernmental Panel on Climate Change (IPCC) and others have presented forecasts of a warmer world and cautioned that some forms of geoengineering might be necessary to deal with climate change in an emergency situation. A debate about geoengineering the climate, held at the European Geosciences Union (EGU) General Assembly on 1 May, explored whether any geoengineering techniques should be considered; if so, which might be acceptable; and what circumstances could necessitate their use. Also discussed was whether potential unintended repercussions from geoengineering could be worse than the problem.

  14. AGU Position Statement: Geoengineering the Climate System

    NASA Astrophysics Data System (ADS)

    2010-04-01

    Human responsibility for most of the well-documented increase in global average temperatures over the last half century is well established. Further greenhouse gas emissions, particularly of carbon dioxide from the burning of fossil fuels, will almost certainly contribute to additional widespread climate changes that can be expected to cause major negative consequences for most nations.1 Three proactive strategies could reduce the risks of climate change: 1) mitigation: reducing emissions; 2) adaptation: moderating climate impacts by increasing our capacity to cope with them; and 3) geoengineering: deliberately manipulating physical, chemical, or biological aspects of the Earth system.2 This policy statement focuses on large-scale efforts to geoengineer the climate system to counteract the consequences of increasing greenhouse gas emissions.

  15. Stratospheric geoengineering with black carbon aerosols

    NASA Astrophysics Data System (ADS)

    Kravitz, Benjamin S.

    I use a general circulation model of Earth's climate to simulate stratospheric geoengineering with black carbon aerosols, varying the altitude of injection, initial particle size, and whether the deposited black carbon modifies ground albedo. 1 Tg of black carbon aerosols injected into the stratosphere each year will cause significant enough surface cooling to negate anthropogenic warming if the aerosols are small (r=0.03 mum) or if the aerosols are injected into the middle stratosphere, although using small aerosols causes large regional cooling effects that would be catastrophic to agriculture. The aerosols cause significant stratospheric heating, resulting in stratospheric ozone destruction and circulation changes, most notably an increase in the Northern Hemisphere polar jet, which forms an Arctic ozone hole and forces a positive mode of the Arctic Oscillation. The hydrologic cycle is perturbed, specifically the summer monsoon system of India, Africa, and East Asia, resulting in monsoon precipitation collapse. Global primary productivity is decreased by 35.5% for the small particle case. Surface cooling causes some sea ice regrowth, but not at statistically significant levels. All of these climate impacts are exacerbated for small particle geoengineering, with high altitude geoengineering with the default particle size (r=0.08 mum) causing a reasonable amount of cooling, and large particle (r=0.15 mum) geoengineering or particle injection into the lower stratosphere causing few of these effects. The modification of ground albedo by the soot particles slightly perturbs the radiative budget but does not cause any distinguishable climate effects. The cheapest means we investigated for placing 1 Tg of black carbon aerosols into the stratosphere by diesel fuel combustion would cost 1.4 trillion initially and 541 billion annual, or 2.0% and 0.8% of GDP, respectively. The additional carbon dioxide released from combusting diesel to produce these aerosols is about 1

  16. Modeling the Climatic Consequences of Geoengineering

    NASA Astrophysics Data System (ADS)

    Somerville, R. C.

    2005-12-01

    The last half-century has seen the development of physically comprehensive computer models of the climate system. These models are the primary tool for making predictions of climate change due to human activities, such as emitting greenhouse gases into the atmosphere. Because scientific understanding of the climate system is incomplete, however, any climate model will necessarily have imperfections. The inevitable uncertainties associated with these models have sometimes been cited as reasons for not taking action to reduce such emissions. Climate models could certainly be employed to predict the results of various attempts at geoengineering, but many questions would arise. For example, in considering proposals to increase the planetary reflectivity by brightening parts of the land surface or by orbiting mirrors, can models be used to bound the results and to warm of unintended consequences? How could confidence limits be placed on such model results? How can climate changes due to proposed geoengineering be distinguished from natural variability? There are historical parallels on smaller scales, in which models have been employed to predict the results of attempts to alter the weather, such as the use of cloud seeding for precipitation enhancement, hail suppression and hurricane modification. However, there are also many lessons to be learned from the recent record of using models to simulate the effects of the great unintended geoengineering experiment involving greenhouse gases, now in progress. In this major research effort, the same types of questions have been studied at length. The best modern models have demonstrated an impressive ability to predict some aspects of climate change. A large body of evidence has already accumulated through comparing model predictions to many observed aspects of recent climate change, ranging from increases in ocean heat content to changes in atmospheric water vapor to reductions in glacier extent. The preponderance of expert

  17. The impacts of Unilateral Stratospheric Geoengineering

    NASA Astrophysics Data System (ADS)

    Jones, A.; Haywood, J. M.; Bellouin, N.; Stephenson, D.

    2013-12-01

    Stratospheric geoengineering proposals have been suggested on the premise that the cooling impacts of volcanic eruptions could be deliberately mimicked to offset the impacts of increased greenhouse gas concentrations in the future by counterbalance global warming. Here, we examine both the impacts of hemispherically asymmetric volcanoes in the observational record and the impact of prolonged deliberate injection of stratospheric aerosol into either the northern or southern hemisphere stratosphere or into both hemispheres equally to assess the impacts on Sahelian rainfall and agriculture (Haywood et al., 2013). While the frequency of volcanic eruptions during the past 100 years is too sparse for definitive attribution, there is a suggestion that volcanic eruptions that preferentially load the northern hemisphere are the harbinger of Sahelian drought. Simulations are then performed with the HadGEM2 couple atmospheric-ocean model to assess the impacts of these volcanic eruptions and deliberate unilateral stratospheric geoengineering. Figure 1 shows the impacts of the geoengineering simulations which show that stratospheric injection into the northern hemisphere induces a severe and prolonged Sahelian drought with undoubted detrimental consequences for the local population. Conversely injection into the southern hemisphere causes a significant greening of the Sahel with vegetation productivity enhanced by over 100%. On the face of it, this suggests potential advocacy of injection into the southern hemisphere: we will investigate potential other side-effects from such a strategy...... Haywood, J.M., A. Jones, N. Bellouin, and D.B. Stephenson, Asymmetric forcing from stratospheric aerosols impacts Sahelian drought, Nature Climate Change, Vol 3, No 7, 660-665, doi: 10.1038/NCLIMATE1857, 2013.

  18. Strategic incentives for climate geoengineering coalitions to exclude broad participation

    NASA Astrophysics Data System (ADS)

    Ricke, Katharine L.; Moreno-Cruz, Juan B.; Caldeira, Ken

    2013-03-01

    Solar geoengineering is the deliberate reduction in the absorption of incoming solar radiation by the Earth’s climate system with the aim of reducing impacts of anthropogenic climate change. Climate model simulations project a diversity of regional outcomes that vary with the amount of solar geoengineering deployed. It is unlikely that a single small actor could implement and sustain global-scale geoengineering that harms much of the world without intervention from harmed world powers. However, a sufficiently powerful international coalition might be able to deploy solar geoengineering. Here, we show that regional differences in climate outcomes create strategic incentives to form coalitions that are as small as possible, while still powerful enough to deploy solar geoengineering. The characteristics of coalitions to geoengineer climate are modeled using a ‘global thermostat setting game’ based on climate model results. Coalition members have incentives to exclude non-members that would prevent implementation of solar geoengineering at a level that is optimal for the existing coalition. These incentives differ markedly from those that dominate international politics of greenhouse-gas emissions reduction, where the central challenge is to compel free riders to participate.

  19. The economics (or lack thereof) of aerosol geoengineering

    NASA Astrophysics Data System (ADS)

    Goes, M.; Keller, K.; Tuana, N.

    2009-04-01

    Anthropogenic greenhouse gas emissions are changing the Earth's climate and impose substantial risks for current and future generations. What are scientifically sound, economically viable, and ethically defendable strategies to manage these climate risks? Ratified international agreements call for a reduction of greenhouse gas emissions to avoid dangerous anthropogenic interference with the climate system. Recent proposals, however, call for the deployment of a different approach: to geoengineer climate by injecting aerosol precursors into the stratosphere. Published economic studies typically suggest that substituting aerosol geoengineering for abatement of carbon dioxide emissions results in large net monetary benefits. However, these studies neglect the risks of aerosol geoengineering due to (i) the potential for future geoengineering failures and (ii) the negative impacts associated with the aerosol forcing. Here we use a simple integrated assessment model of climate change to analyze potential economic impacts of aerosol geoengineering strategies over a wide range of uncertain parameters such as climate sensitivity, the economic damages due to climate change, and the economic damages due to aerosol geoengineering forcing. The simplicity of the model provides the advantages of parsimony and transparency, but it also imposes severe caveats on the interpretation of the results. For example, the analysis is based on a globally aggregated model and is hence silent on the question of intragenerational distribution of costs and benefits. In addition, the analysis neglects the effects of endogenous learning about the climate system. We show that the risks associated with a future geoengineering failure and negative impacts of aerosol forcings can cause geoenginering strategies to fail an economic cost-benefit test. One key to this finding is that a geoengineering failure would lead to dramatic and abrupt climatic changes. The monetary damages due to this failure can

  20. Geoengineering and the Risk of Rapid Climate Change

    NASA Astrophysics Data System (ADS)

    Ross, A. J.; Matthews, D.

    2008-12-01

    Many scientists have proposed that geoengineering could be used to artificially cool the planet as a means of reducing CO2-induced climate warming. However, several recent studies have shown some of the potential risks of geoengineering, including negative impacts on stratospheric ozone, the hydrologic cycle and the possibility of rapid climate change in the case of abrupt failure, or rapid decommissioning of geoengineering technology. In this study, we have emulated a geoengineering scenario in the MAGICC climate model, by counteracting the radiative forcing from greenhouse gases. We have used a hypothetical scenario of business-as-usual greenhouse gas emissions, in which geoengineering is implemented at the year 2020, and is removed abruptly after 40 years. By varying the climate sensitivity of the MAGICC model, and using previously published estimates of climate sensitivity likelihoods, we are able to derive a probabilistic prediction of the rate of temperature change following the removal of geoengineering. In a simulation without geoengineering (considering only the A1B AIM emissions scenario) the maximum annual rate of temperature change (in the highest climate sensitivity simulation) was 0.5° C per decade. In the geoengineering simulations the maximum annual rate of temperature change, occurring in the year after geoengineering was stopped, varied from 0.22° C per decade for a climate sensitivity of 0.5° C to nearly 8° C per decade for a climate sensitivity of 10° C. The most likely maximum rate of change (corresponding to a climate sensitivity of 2.5° C) was just over 5° C per decade. There is a 99.8 percent probability that the rate of temperature change following the stoppage of geoengineering in this scenario would exceed 3° C per decade. This risk of rapid climate change associated with the use of planetary-scale geoengineering is highly relevant to discussion of climate policies aimed at avoiding "dangerous anthropogenic interference" in the

  1. Geoengineering to Avoid Overshoot: An Analysis of Uncertainty

    NASA Astrophysics Data System (ADS)

    Tanaka, Katsumasa; Cho, Cheolhung; Krey, Volker; Patt, Anthony; Rafaj, Peter; Rao-Skirbekk, Shilpa; Wagner, Fabian

    2010-05-01

    Even if a drastic 50% CO2-equivalent emissions reduction is achieved by year 2050, the chances of exceeding a 2°C warming are still substantial due to the uncertainty in the climate system (Meinshausen et al., 2009). Moreover, a strong mitigation is accompanied by overshoot, in which the global-mean temperature temporarily exceeds the target before arriving there. We are motivated by the question as to how much geoengineering would be considered if it were to be used to avoid overshoot even combined with a strong mitigation? How serious would the side effects be expected? This study focuses on stratospheric sulfur injections among other geoengineering proposals, the idea of which has been put forward by Crutzen (2006) and reviewed by Rasch et al. (2008). There are a number of concerns over geoengineering (e.g. Robock, 2008). But the concept of geoengineering requires further research (AMS, 2009). Studying geoengineering may be instructive to revisit the importance of mainstream mitigation strategies. The motivations above led to the following two closely linked studies: 1) Mitigation and Geoengineering The first study investigates the magnitude and start year of geoengineering intervention with the intent to avoid overshoot. This study explores the sensitivity of geoengineering profile to associated uncertainties in the climate system (climate sensitivity, tropospheric aerosol forcing, and ocean diffusivity) and in mitigation scenarios (target uncertainty (450ppm CO2-eq and 400ppm CO2-eq) and baseline uncertainty (A2, B1, and B2)). This study builds on Wigley's premise that demonstrated a basic potential of such a combined mitigation/geoengineering approach (Wigley, 2006) - however it did not examine the sensitivity of the climate response to any underlying uncertainties. This study uses a set of GGI low mitigation scenarios generated from the MESSAGE model (Riahi et al., 2007). The reduced-complexity climate and carbon cycle model ACC2 (Tanaka, 2008; Tanaka et al

  2. Simulated long-term climate response to idealized solar geoengineering

    NASA Astrophysics Data System (ADS)

    Cao, Long; Duan, Lei; Bala, Govindasamy; Caldeira, Ken

    2016-03-01

    Solar geoengineering has been proposed as a potential means to counteract anthropogenic climate change, yet it is unknown how such climate intervention might affect the Earth's climate on the millennial time scale. Here we use the HadCM3L model to conduct a 1000 year sunshade geoengineering simulation in which solar irradiance is uniformly reduced by 4% to approximately offset global mean warming from an abrupt quadrupling of atmospheric CO2. During the 1000 year period, modeled global climate, including temperature, hydrological cycle, and ocean circulation of the high-CO2 simulation departs substantially from that of the control preindustrial simulation, whereas the climate of the geoengineering simulation remains much closer to that of the preindustrial state with little drift. The results of our study do not support the hypothesis that nonlinearities in the climate system would cause substantial drift in the climate system if solar geoengineering was to be deployed on the timescale of a millennium.

  3. Geoengineering, news media and metaphors: Framing the controversial.

    PubMed

    Luokkanen, Matti; Huttunen, Suvi; Hildén, Mikael

    2014-11-01

    We analyze how metaphors are used in presenting and debating novel technologies that could influence the climate and thereby also future climate change policies. We show that metaphors strengthen a policy-related storyline, while metaphors are rarer in purely descriptive accounts. The choice of metaphor frames the technologies. War metaphors are used equally in arguments that are for, against and neutral with respect to the further development of geoengineering, but differences arise in the use of metaphors related to controllability, health and mechanisms. Controllability metaphors are often used in justifying further research and development of good governance practices, whereas health metaphors tend to be used against the very idea of geoengineering by portraying technological interventions in the climate as an emblematic case of an unacceptable development. These findings suggest that metaphors are early indications of restrictions in the interpretative flexibility that influences future governance of geoengineering and geoengineering research. PMID:23825283

  4. Is geo-engineering just geophysics in disguise?

    NASA Astrophysics Data System (ADS)

    Khan, A.

    2008-10-01

    There's a bit of a buzz around the topic of geo-engineering. The UK government's Innovation, Universities, Science and Skills Committee has asked for submissions to its case study on engineering on this theme, and the Royal Society has published a special journal issue, against a background of rising public concern about climate change. Sue Bowler considers how geophysics fits into geo-engineering, now and in the future.

  5. Stratospheric changes caused by geoengineering aerosols

    NASA Astrophysics Data System (ADS)

    Heckendorn, P.; Peter, T.; Weisenstein, D.; Luo, B. P.; Rozanov, E.; Fueglistaler, S.; Thomason, L. W.

    2010-05-01

    Anthropogenic greenhouse gas emissions are warming the global climate at an unprecedented rate. Significant emission reductions will be required soon to avoid a rapid temperature rise. One of the most prominent geoengineering ideas to counteract global warming is the increase of Earth's albedo by artificially enhancing stratospheric sulphate aerosols. This idea is based on the observed increase of atmospheric optical thickness after volcanic eruptions. The most straightforward method, from a technical point of view, is to inject sulphur in the tropical stratosphere. We use a 3D chemistry climate model, fed by aerosol size distributions from a zonal mean aerosol model, to simulate continuous injection of 1-10 Mt/a sulphur in form of SO2 into the lower tropical stratosphere. The volcanic and geoengineering forcings differ in terms of their radiative, chemical and dynamical impact on climate, mainly because the geoengineering forcing has to be continuously applied over a long period of time, whereas volcanic eruptions are single events, leading to a non-linear relationship between annual sulphur input and stratospheric sulphur burden. The reason is the continuous supply of sulphuric acid and hence freshly formed small aerosol particles, which enhance the formation of large aerosol particles by coagulation and, to a lesser extent, also by condensation. This shows the importance of investigating carefully the microphysics of the sulphate aerosols. The growth of the particles is sensitive to the injection region and the sulphur loading per injection time. The consequences of the formation of large particles lead to notable disadvantages. Larger particles are less efficient in cooling than small particles with the same mass. Furthermore, a large fraction of the emitted sulphur is lost rapidly by gravitational settling and subsequent tropospheric washout. Hence, larger sulphur amounts are needed to achieve a targeted cooling. Some particles are trapped in the tropopause

  6. Effects of geoengineering on crop yields

    NASA Astrophysics Data System (ADS)

    Pongratz, J.; Lobell, D. B.; Cao, L.; Caldeira, K.

    2011-12-01

    The potential of "solar radiation management" (SRM) to reduce future climate change and associated risks has been receiving significant attention in scientific and policy circles. SRM schemes aim to reduce global warming despite increasing atmospheric CO2 concentrations by diminishing the amount of solar insolation absorbed by the Earth, for example, by injecting scattering aerosols into the atmosphere. Climate models predict that SRM could fully compensate warming at the global mean in a high-CO2 world. While reduction of global warming may offset a part of the predicted negative effects of future climate change on crop yields, SRM schemes are expected to alter regional climate and to have substantial effects on climate variables other than temperature, such as precipitation. It has therefore been warned that, overall, SRM may pose a risk to food security. Assessments of benefits and risks of geoengineering are imperative, yet such assessments are only beginning to emerge; in particular, effects on global food security have not previously been assessed. Here, for the first time, we combine climate model simulations with models of crop yield responses to climate to assess large-scale changes in yields and food production under SRM. In most crop-growing regions, we find that yield losses caused by climate changes are substantially reduced under SRM as compared with a non-geoengineered doubling of atmospheric CO2. Substantial yield losses with SRM are only found for rice in high latitudes, where the limits of low temperatures are no longer alleviated. At the same time, the beneficial effect of CO2-fertilization on plant productivity remains active. Overall therefore, SRM in our models causes global crop yields to increase. We estimate the direct effects of climate and CO2 changes on crop production, and do not quantify effects of market dynamics and management changes. We note, however, that an SRM deployment would be unlikely to maintain the economic status quo, as

  7. The Hydrological Impact of Geoengineering in the Geoengineering Model Intercomparison Project (GeoMIP)

    SciTech Connect

    Tilmes, S.; Fasullo, John; Lamarque, J.-F.; Marsh, D.; Mills, Mike; Alterskjaer, Kari; Muri, Helene O.; Kristjansson, Jon E.; Boucher, Olivier; Schulz, M.; Cole, Jason N.; Curry, Charles L.; Jones, A.; Haywood, J.; Irvine, Peter; Ji, Duoying; Moore, John; Bou Karam, Diana; Kravitz, Benjamin S.; Rasch, Philip J.; Singh, Balwinder; Yoon, Jin-Ho; Niemeier, Ulrike; Schmidt, Hauke; Robock, Alan; Yang, Shuting; Watanabe, Shingo

    2013-10-14

    Abstract: The hydrologic impact of enhancing Earth’s albedo due to solar radiation management (SRM) is investigated using simulations from 12 models contributing to the Geoengineering Model Intercomparison Project (GeoMIP). An artificial experiment is investigated, where global mean temperature is preserved at pre-industrial conditions, while atmospheric carbon dioxide concentrations are quadrupled. The associated reduction of downwelling surface solar radiation in a high CO2 environment leads to a reduction of global evaporation of 10% and 4% and precipitation of 6.1% and 6.3% over land and ocean, respectively. An initial reduction of latent heat flux at the surface is largely driven by reduced evapotranspiration over land with instantly increasing CO2 concentrations in both experiments. A warming surface associated with the transient adjustment in the 4xCO2 experiment further generates an increase of global precipitation, with considerable regional changes, such as a significant precipitation reduction of 7% for the North American summer monsoon. Reduced global precipitation persists in the geoengineered experiment where temperatures are stabilized, with considerable regional rainfall deficits. Precipitation reductions that are consistent in sign across models are identified in the geoengineered experiment over monsoonal land regions of East Asia (6%), North America (7%), South America (6%) and South Africa (5%). In contrast to the 4xCO2 experiment, where the frequency of months with heavy precipitation intensity is increased by over 50%, it is reduced by up to 20% in the geoengineering scenario . The reduction in heavy precipitation is more pronounced over land than over the ocean, and accompanies a stronger reduction in evaporation over land. For northern mid-latitudes, maximum precipitation reduction over land ranges from 1 to 16% for individual models. For 45-65°N, the frequency of median to high intensity precipitation in summer is strongly reduced. These

  8. Impact of geoengineering on cirrus clouds

    NASA Astrophysics Data System (ADS)

    Cirisan, Ana; Spichtinger, Peter; Weisenstein, Debra; Lohmann, Ulrike; Wernli, Heini; Peter, Thomas

    2010-05-01

    Inspite of the framework convention agreement, climate warming is still an actual and very important issue society has to deal with. This has motivated some scientist to start thinking about implementation of artificial methods that could change the climate and weather patterns in order to stop or reverse the global warming effects. Nowadays, there is a consortium of politicians, scientists and engineers interested in evaluating different geoengineering schemes as a way to mitigate global warming, discount rates, and risk aversion (Polborn S. and Tintelnot F., 2009). The geoengineering proposal attracting the most attention and having considerably lower expected deployment costs than conventional emissions abatement approaches (Nordhaus, 2007) is stratospheric aerosol injection. This method, proposed by Budyko (1977) and Crutzen (2006), relies on the fact that large amounts of sulphur aerosols injected into the lower stratosphere enhance the Earth's albedo and lead to cooling of the globe. This proposal is currently discussed in the climate community and possible side effects are investigated. However, the investigations concentrate almost exclusively on the impact on chemistry and stratospheric circulation, whereas the impact on cirrus clouds in the underlying tropopause and upper troposphere region was not taken into account up to now. In this contribution we investigated the impact of artificially produced sulphate aerosol concentrations, modeled with the AER 2D aerosol model (Weisenstein et al., 2007), on the formation and evolution of cirrus clouds in the mid-latitudes. For large injections of SO2 some sulphate aerosol particles grow to large sizes that they can sediment to lower altitudes and eventually reach the troposphere, where they can influence ice crystal formation. Investigations are carried out using a bulk microphysical box model (Spichtinger and Gierens, 2009, Spichtinger and Cziczo, 2009), concentrating on moderate constant updrafts with different

  9. A Symposium.

    ERIC Educational Resources Information Center

    Rachal, John R.

    2003-01-01

    Uses the framework of a symposium to present an imagined discussion by historical figures about whether and how knowledge might be acquired. Discussants include Democritus, Protagoras, Heraclitus, Socrates, Jesus, Gorgias, Nietzsche, Buddha, and Kierkegaard. (Contains 40 endnotes.) (SK)

  10. The economics and ethics of aerosol geoengineering strategies

    NASA Astrophysics Data System (ADS)

    Goes, Marlos; Keller, Klaus; Tuana, Nancy

    2010-05-01

    Anthropogenic greenhouse gas emissions are changing the Earth's climate and impose substantial risks for current and future generations. What are scientifically sound, economically viable, and ethically defendable strategies to manage these climate risks? Ratified international agreements call for a reduction of greenhouse gas emissions to avoid dangerous anthropogenic interference with the climate system. Recent proposals, however, call for a different approach: geoengineering climate by injecting aerosol precursors into the stratosphere. Published economic studies typically neglect the risks of aerosol geoengineering due to (i) a potential failure to sustain the aerosol forcing and (ii) due to potential negative impacts associated with aerosol forcings. Here we use a simple integrated assessment model of climate change to analyze potential economic impacts of aerosol geoengineering strategies over a wide range of uncertain parameters such as climate sensitivity, the economic damages due to climate change, and the economic damages due to aerosol geoengineering forcings. The simplicity of the model provides the advantages of parsimony and transparency, but it also imposes considerable caveats. For example, the analysis is based on a globally aggregated model and is hence silent on intragenerational distribution of costs and benefits. In addition, the analysis neglects the effects of future learning and is based on a simple representation of climate change impacts. We use this integrated assessment model to show three main points. First, substituting aerosol geoengineering for the reduction of greenhouse gas emissions can fail the test of economic efficiency. One key to this finding is that a failure to sustain the aerosol forcing can lead to sizeable and abrupt climatic changes. The monetary damages due to such a discontinuous aerosol geoengineering can dominate the cost-benefit analysis because the monetary damages of climate change are expected to increase with

  11. Stratospheric sulfate geoengineering could enhance the terrestrial photosynthesis rate

    NASA Astrophysics Data System (ADS)

    Xia, L.; Robock, A.; Tilmes, S.; Neely, R. R., III

    2016-02-01

    Stratospheric sulfate geoengineering could impact the terrestrial carbon cycle by enhancing the carbon sink. With an 8 Tg yr-1 injection of SO2 to produce a stratospheric aerosol cloud to balance anthropogenic radiative forcing from the Representative Concentration Pathway 6.0 (RCP6.0) scenario, we conducted climate model simulations with the Community Earth System Model - the Community Atmospheric Model 4 fully coupled to tropospheric and stratospheric chemistry (CAM4-chem). During the geoengineering period, as compared to RCP6.0, land-averaged downward visible (300-700 nm) diffuse radiation increased 3.2 W m-2 (11 %). The enhanced diffuse radiation combined with the cooling increased plant photosynthesis by 0.07 ± 0.02 µmol C m-2 s-1, which could contribute to an additional 3.8 ± 1.1 Gt C yr-1 global gross primary productivity without explicit nutrient limitation. This increase could potentially increase the land carbon sink. Suppressed plant and soil respiration due to the cooling would reduce natural land carbon emission and therefore further enhance the terrestrial carbon sink during the geoengineering period. This potentially beneficial impact of stratospheric sulfate geoengineering would need to be balanced by a large number of potential risks in any future decisions about the implementation of geoengineering.

  12. Ethics as an Integral Component of Geoengineering Analysis

    NASA Astrophysics Data System (ADS)

    Haqq-Misra, J.; Tuana, N.; Keller, K.; Sriver, R. L.; Svoboda, T.; Tonkonojenkov, R.; Irvine, P. J.

    2011-12-01

    Concerns about the risks of unmitigated greenhouse gas emissions are growing. At the same time, confidence is declining that international policy agreements will succeed in considerably lowering anthropogenic greenhouse gas emissions. Perhaps as a result, various geoengineering solutions are gaining attention and credibility as a way to manage climate change. Serious consideration is currently being given to proposals to cool the planet through solar-radiation management (SRM). Here we analyze how the unique and nontrivial risks of geoengineering strategies pose fundamental questions at the interface between science and ethics. We define key open questions to analyze SRM geoengineering proposals, which include whether SRM can be tested, how quickly learning could occur, normative decisions embedded in how different climate trajectories are valued, and justice issues regarding distribution of the harms and benefits of geoengineering. To ensure that ethical analyses are coupled with scientific analyses of this form of geoengineering, we advocate that funding agencies recognize the essential nature of this coupled research by establishing an Ethical, Legal, and Social Implications (ELSI) program for SRM.

  13. Stratospheric sulfate geoengineering enhances terrestrial gross primary productivity

    NASA Astrophysics Data System (ADS)

    Xia, L.; Robock, A.; Tilmes, S.; Neely, R. R., III

    2015-09-01

    Stratospheric sulfate geoengineering could impact the terrestrial carbon cycle by enhancing the carbon sink. With an 8 Tg yr-1 injection of SO2 to balance a Representative Concentration Pathway 6.0 (RCP6.0) scenario, we conducted climate model simulations with the Community Earth System Model, with the Community Atmospheric Model 4 fully coupled to tropospheric and stratospheric chemistry (CAM4-chem). During the geoengineering period, as compared to RCP6.0, land-averaged downward visible diffuse radiation increased 3.2 W m-2 (11 %). The enhanced diffuse radiation combined with the cooling increased plant photosynthesis by 2.4 %, which could contribute to an additional 3.8 ± 1.1 Gt C yr-1 global gross primary productivity without nutrient limitation. This increase could potentially increase the land carbon sink. Suppressed plant and soil respiration due to the cooling would reduce natural land carbon emission and therefore further enhance the terrestrial carbon sink during the geoengineering period. This beneficial impact of stratospheric sulfate geoengineering would need to be balanced by a large number of potential risks in any future decisions about implementation of geoengineering.

  14. Geoengineering: re-making climate for profit or humanitarian intervention?

    PubMed

    Buck, Holly Jean

    2012-01-01

    Climate engineering, or geoengineering, refers to large-scale climate interventions to lower the earth's temperature, either by blocking incoming sunlight or removing carbon dioxide from the biosphere. Regarded as ‘technofixes’ by critics, these strategies have evoked concern that they would extend the shelf life of fossil-fuel driven socio-ecological systems for far longer than they otherwise would, or should, endure. A critical reading views geoengineering as a class project that is designed to keep the climate system stable enough for existing production systems to continue operating. This article first examines these concerns, and then goes on to envision a regime driven by humanitarian agendas and concern for vulnerable populations, implemented through international development and aid institutions. The motivations of those who fund research and implement geoengineering techniques are important, as the rationale for developing geoengineering strategies will determine which techniques are pursued, and hence which ecologies are produced. The logic that shapes the geoengineering research process could potentially influence social ecologies centuries from now. PMID:22662349

  15. Geoengineering to Avoid Overshoot: An Analysis of Uncertainty

    NASA Astrophysics Data System (ADS)

    Tanaka, Katsumasa; Cho, Cheolhung; Krey, Volker; Patt, Anthony; Rafaj, Peter; Rao-Skirbekk, Shilpa; Wagner, Fabian

    2010-05-01

    Even if a drastic 50% CO2-equivalent emissions reduction is achieved by year 2050, the chances of exceeding a 2°C warming are still substantial due to the uncertainty in the climate system (Meinshausen et al., 2009). Moreover, a strong mitigation is accompanied by overshoot, in which the global-mean temperature temporarily exceeds the target before arriving there. We are motivated by the question as to how much geoengineering would be considered if it were to be used to avoid overshoot even combined with a strong mitigation? How serious would the side effects be expected? This study focuses on stratospheric sulfur injections among other geoengineering proposals, the idea of which has been put forward by Crutzen (2006) and reviewed by Rasch et al. (2008). There are a number of concerns over geoengineering (e.g. Robock, 2008). But the concept of geoengineering requires further research (AMS, 2009). Studying geoengineering may be instructive to revisit the importance of mainstream mitigation strategies. The motivations above led to the following two closely linked studies: 1) Mitigation and Geoengineering The first study investigates the magnitude and start year of geoengineering intervention with the intent to avoid overshoot. This study explores the sensitivity of geoengineering profile to associated uncertainties in the climate system (climate sensitivity, tropospheric aerosol forcing, and ocean diffusivity) and in mitigation scenarios (target uncertainty (450ppm CO2-eq and 400ppm CO2-eq) and baseline uncertainty (A2, B1, and B2)). This study builds on Wigley's premise that demonstrated a basic potential of such a combined mitigation/geoengineering approach (Wigley, 2006) - however it did not examine the sensitivity of the climate response to any underlying uncertainties. This study uses a set of GGI low mitigation scenarios generated from the MESSAGE model (Riahi et al., 2007). The reduced-complexity climate and carbon cycle model ACC2 (Tanaka, 2008; Tanaka et al

  16. Friday Letters: Connecting Students, Teachers, and Families through Writing

    ERIC Educational Resources Information Center

    Newman, Terry H.; Bizzarri, Sarah A.

    2012-01-01

    An important part of student success in school is the involvement of families. However, the communication between students and families regarding school is often sparse at best and caregivers can feel left out as to what is happening. Friday letters improve communication between students and families and also provide a myriad of instructional…

  17. Irish Speakers in Northern Ireland, and the Good Friday Agreement.

    ERIC Educational Resources Information Center

    Craith, M. Nic

    1999-01-01

    Examines the Irish language community in Northern Ireland, and questions the validity of the census results of 1991. Particular focus is on the concept of a mother tongue and its relevance for speakers of Irish in the United Kingdom. Discusses measures to improve the status of Irish as a result of the Good Friday Agreement. (Author/VWL)

  18. Ocean acidification in a geoengineering context

    PubMed Central

    Williamson, Phillip; Turley, Carol

    2012-01-01

    Fundamental changes to marine chemistry are occurring because of increasing carbon dioxide (CO2) in the atmosphere. Ocean acidity (H+ concentration) and bicarbonate ion concentrations are increasing, whereas carbonate ion concentrations are decreasing. There has already been an average pH decrease of 0.1 in the upper ocean, and continued unconstrained carbon emissions would further reduce average upper ocean pH by approximately 0.3 by 2100. Laboratory experiments, observations and projections indicate that such ocean acidification may have ecological and biogeochemical impacts that last for many thousands of years. The future magnitude of such effects will be very closely linked to atmospheric CO2; they will, therefore, depend on the success of emission reduction, and could also be constrained by geoengineering based on most carbon dioxide removal (CDR) techniques. However, some ocean-based CDR approaches would (if deployed on a climatically significant scale) re-locate acidification from the upper ocean to the seafloor or elsewhere in the ocean interior. If solar radiation management were to be the main policy response to counteract global warming, ocean acidification would continue to be driven by increases in atmospheric CO2, although with additional temperature-related effects on CO2 and CaCO3 solubility and terrestrial carbon sequestration. PMID:22869801

  19. Regional Scale Analysis of Extremes in an SRM Geoengineering Simulation

    NASA Astrophysics Data System (ADS)

    Muthyala, R.; Bala, G.

    2014-12-01

    Only a few studies in the past have investigated the statistics of extreme events under geoengineering. In this study, a global climate model is used to investigate the impact of solar radiation management on extreme precipitation events on regional scale. Solar constant was reduced by 2.25% to counteract the global mean surface temperature change caused by a doubling of CO2 (2XCO2) from its preindustrial control value. Using daily precipitation rates, extreme events are defined as those which exceed 99.9th percentile precipitation threshold. Extremes are substantially reduced in geoengineering simulation: the magnitude of change is much smaller than those that occur in a simulation with doubled CO2. Regional analysis over 22 Giorgi land regions is also performed. Doubling of CO2 leads to an increase in intensity of extreme (99.9th percentile) precipitation by 17.7% on global-mean basis with maximum increase in intensity over South Asian region by 37%. In the geoengineering simulation, there is a global-mean reduction in intensity of 3.8%, with a maximum reduction over Tropical Ocean by 8.9%. Further, we find that the doubled CO2 simulation shows an increase in the frequency of extremes (>50 mm/day) by 50-200% with a global mean increase of 80%. In contrast, in geo-engineering climate there is a decrease in frequency of extreme events by 20% globally with a larger decrease over Tropical Ocean by 30%. In both the climate states (2XCO2 and geo-engineering) change in "extremes" is always greater than change in "means" over large domains. We conclude that changes in precipitation extremes are larger in 2XCO2 scenario compared to preindustrial climate while extremes decline slightly in the geoengineered climate. We are also investigating the changes in extreme statistics for daily maximum and minimum temperature, evapotranspiration and vegetation productivity. Results will be presented at the meeting.

  20. Biochronometry; Proceedings of the Symposium, Friday Harbor, Wash., September 4-6, 1969.

    NASA Technical Reports Server (NTRS)

    Menaker, M.

    1971-01-01

    Topics discussed include circadian activity rhythms in birds and man, variation of circadian rhythms in monkeys, resetting of circadian eclosion rhythm in fruitflies, the effectiveness of mathematical models of circadian rhythms, the influence of ac electric fields on circadian rhythms in man, the relation between changes in the metabolic rate and circadian periodicity of the resistance of pocket mice to ionizing radiation, the relation between circadian organization and the photoperiodic time measurement in moths, the circadian rhythm of optic nerve potentials in the isolated eye of the sea hare, phasing of circadian temperature rhythms in the pocket mouse by specific spectral regions, the phase-shifting effect of light on circadian rhymicity in the fruifly, hormonal control of circadian rhythms in the fruitfly, metabolically controlled temperature compensation in the circadian rhythm of algae, and circadian rhythms in the chloroplasts of algae. Individual items are abstracted in this issue.

  1. Symposium Summary

    NASA Astrophysics Data System (ADS)

    Milner, Richard G.

    2016-02-01

    The Stern-Gerlach experiment and the origin of electron spin are described in historical context. SPIN 2014 occurs on the fortieth anniversary of the first International High Energy Spin Physics Symposium at Argonne in 1974. A brief history of the international spin conference series is presented.

  2. Symposium: Assessment

    ERIC Educational Resources Information Center

    Anson, Chris M.; Perelman, Les; Poe, Mya; Sommers, Nancy

    2008-01-01

    This article presents four symposium papers on assessment. It includes: (1) "Closed Systems and Standardized Writing Tests" (Chris M. Anson); (2) "Information Illiteracy and Mass Market Writing Assessments" (Les Perelman); (3) "Genre, Testing, and the Constructed Realities of Student Achievement" (Mya Poe); and (4) "The Call of Research: A…

  3. Additional risk of end-of-the-pipe geoengineering technologies

    NASA Astrophysics Data System (ADS)

    Bohle, Martin

    2014-05-01

    Humans are engineers, even the artists who engineer the surface of the globe. Should humans endeavour to engineer the Earth to counter climate change hazards? Striving towards 'global sustainability' will require to adjust the current production and consumption patterns. Contrary to an approach of global sustainability, 'geoengineering' deploys a 'technology fix' for the same purpose. Humans are much inclined to look for technological fixes for problems because well engineered technological methods have created modern societies. Thus, it seems obvious to apply an engineering solution to climate change issues too. In particular, as air pollution causing acid rains has been reduced by cleaner combustion processes or ozone destructing chemical coolants have been replaced by other substances. Common to these approaches was to reduce inputs into global or regional systems by withholding emission, replacing substances or limiting use cases for certain substances. Thus, the selected approach was a technological fix or regulatory measure targeting the 'start of the pipe'. However applying a 'start of the pipe' approach to climate change faces the issue that mankind should reduce inputs were its hurts, namely reducing radically energy that is produced from burning fossil fuels. Capping burning of fossil fuels would be disruptive for the economic structures or the consumption pattern of the developed and developing industrialised societies. Facing that dilemma, affordable geoengineering looks tempting for some. However geoengineering technologies, which counter climate change by other means than carbon capture at combustion, are of a different nature than the technological fixes and negotiated regulatory actions, which so far have been applied to limit threats to regional and global systems. Most of the proposed technologies target other parts of the climate system but the carbon-dioxide input into the atmosphere. Therefore, many geoengineering technologies differ

  4. Solar geoengineering, atmospheric water vapor transport, and land plants

    NASA Astrophysics Data System (ADS)

    Caldeira, Ken; Cao, Long

    2015-04-01

    This work, using the GeoMIP database supplemented by additional simulations, discusses how solar geoengineering, as projected by the climate models, affects temperature and the hydrological cycle, and how this in turn is related to projected changes in net primary productivity (NPP). Solar geoengineering simulations typically exhibit reduced precipitation. Solar geoengineering reduces precipitation because solar geoengineering reduces evaporation. Evaporation precedes precipitation, and, globally, evaporation equals precipitation. CO2 tends to reduce evaporation through two main mechanisms: (1) CO2 tends to stabilize the atmosphere especially over the ocean, leading to a moister atmospheric boundary layer over the ocean. This moistening of the boundary layer suppresses evaporation. (2) CO2 tends to diminish evapotranspiration, at least in most land-surface models, because higher atmospheric CO2 concentrations allow leaves to close their stomata and avoid water loss. In most high-CO2 simulations, these effects of CO2 which tend to suppress evaporation are masked by the tendency of CO2-warming effect to increase evaporation. In a geoengineering simulation, with the warming effect of CO2 largely offset by the solar geoengineering, the evaporation suppressing characteristics of CO2 are no longer masked and are clearly exhibited. Decreased precipitation in solar geoengineering simulations is a bit like ocean acidification - an effect of high CO2 concentrations that is not offset by solar geoengineering. Locally, precipitation ultimately either evaporates (much of that through the leaves of plants) or runs off through groundwater to streams and rivers. On long time scales, runoff equals precipitation minus evaporation, and thus, water runoff generated at a location is equal to the net atmospheric transport of water to that location. Runoff typically occurs where there is substantial soil moisture, at least seasonally. Locations where there is enough water to maintain

  5. Effects of Stratospheric Sulfate Geoengineering on Food Supply in China

    NASA Astrophysics Data System (ADS)

    Xia, L.; Robock, A.

    2010-12-01

    Possible food supply change is one of the most important concerns in the discussion of stratospheric geoengineering. In regions with high population density, climate changes such as precipitation reduction spurred by stratospheric sulfate injection may cause drought, reduce crop yield, and affect the food supply for hundreds of millions of people. Therefore, as part of the research into the benefits and risks of stratospheric geoengineering, it is necessary to fully investigate its effects on the regional climate system and crop yields, which is the goal of this study. In particular, we focus on China, not only because of its high risk to experience severe regional climate change after stratospheric geoengineering, but also because of its high vulnerability due to a large share of its population living on agriculture. To examine the effects of climate changes induced by geoengineering on Chinese agriculture, we use the DSSAT and CLICROP agricultural simulation models. We first evaluate these models by forcing them with daily weather data and management practices for the period 1978-2008 for all the provinces in China, and compare the results to observations of the yields of major crops in China (early season paddy, double crop paddy, spring wheat, winter wheat, corn, sorghum and soybean). Overall, there is a strong upward trend in both yield and fertilizer use, but interannual variations can be associated with temperature and precipitation variations. Using climate model simulations with the NASA GISS general circulation model forced by both a standard global warming scenario (A1B) and A1B combined with stratospheric geoengineering, we then apply scenarios of changes of precipitation and temperature from these runs to examine their effects on Chinese agricultural production. Compared to global warming only, the geoengineering runs produced summer precipitation reductions in northeastern China but precipitation increases in the Yangtze River region. Without changes

  6. Geoengineering, Climate Harm, and Business as Usual

    NASA Astrophysics Data System (ADS)

    Jankunis, F. J.; Peacock, K.

    2014-12-01

    We define geoengineering (GE) as the intentional use of technology to change the planet's climate. Many people believe GE is different in kind rather than degree from any other organized activity in human history. In fact, humans caused changes in the planet's climate long before the industrial age, and all organisms engineer their environments directly or indirectly. The relevant difference between this cumulative and generally inadvertent activity and GE is the presence of intention. Now that science has revealed the extent to which humans can change the climate, however, even the continuance of Business as Usual (BAU) is, in effect, a form of intentional GE, albeit one that will cause significant climate harm, defined as effects such as sea level rise that will impact human well-being. But as with all forms of engineering, the devil is in the details: what forms of GE should be tried first? Some methods, such as large-scale afforestation, are low risk but have long-term payoffs; others, such as aerosol injection into the stratosphere, could help buy time in a warming crisis but have unknown side-effects and little long-term future. Climate change is a world-wide, inter-generational tragedy of the commons. Rational choice theory, the spatial and temporal extension of the problem, poorly fitted moral frameworks, and political maneuvering are all factors that inhibit solutions to the climate tragedy of the commons. The longer that such factors are allowed to dominate decision-making (or the lack thereof) the more likely it is that humanity will be forced to resort to riskier and more drastic forms of GE. We argue that this fact brings an additional measure of urgency to the search for ways to engineer the climate differently so as to avoid climate harm in the most lasting and least risky way.

  7. Impact of geoengineered aerosols on the troposphere and stratosphere

    SciTech Connect

    Tilmes, S.; Garcia, Rolando R.; Kinnison, Douglas E.; Gettelman, A.; Rasch, Philip J.

    2009-06-27

    A coupled chemistry climate model, the Whole Atmosphere Community Climate Model was used to perform a transient climate simulation to quantify the impact of geoengineered aerosols on atmospheric processes. In contrast to previous model studies, the impact on stratospheric chemistry, including heterogeneous chemistry in the polar regions, is considered in this simulation. In the geoengineering simulation, a constant stratospheric distribution of volcanic-sized, liquid sulfate aerosols is imposed in the period 2020–2050, corresponding to an injection of 2 Tg S/a. The aerosol cools the troposphere compared to a baseline simulation. Assuming an Intergovernmental Panel on Climate Change A1B emission scenario, global warming is delayed by about 40 years in the troposphere with respect to the baseline scenario. Large local changes of precipitation and temperatures may occur as a result of geoengineering. Comparison with simulations carried out with the Community Atmosphere Model indicates the importance of stratospheric processes for estimating the impact of stratospheric aerosols on the Earth’s climate. Changes in stratospheric dynamics and chemistry, especially faster heterogeneous reactions, reduce the recovery of the ozone layer in middle and high latitudes for the Southern Hemisphere. In the geoengineering case, the recovery of the Antarctic ozone hole is delayed by about 30 years on the basis of this model simulation. For the Northern Hemisphere, a onefold to twofold increase of the chemical ozone depletion occurs owing to a simulated stronger polar vortex and colder temperatures compared to the baseline simulation, in agreement with observational estimates.

  8. Impacts of Stratospheric Sulfate Geoengineering on Chinese Agricultural Production

    NASA Astrophysics Data System (ADS)

    Xia, L.; Robock, A.

    2012-12-01

    Possible food supply change is one of the most important concerns in the discussion of stratospheric sulfate geoengineering. In China, the high population density and strong summer monsoon influence on agriculture make this region sensitive to climate changes, such as reductions of precipitation, temperature, and solar radiation spurred by stratospheric sulfate injection. We used results from the Geoengineering Model Intercomparison Project G2 scenario to force the Decision Support System for Agrotechnology Transfer (DSSAT) crop model to predict crop yield changes from rice, maize, and winter wheat. We first evaluated the DSSAT model by forcing it with daily observed weather data and management practices for the period 1978-2008 for all the provinces in China, and compared the results to observations of the yields of the three major crops in China. We then created two 50-year sets of climate anomalies using the results from eight climate models, for 1%/year increase of CO2 and for G2 (1%/year increase of CO2 balanced by insolation reduction), and compared the resulting agricultural responses. Considering that geoengineering could happen in the future, we used two geoengineering starting years, 2020 and 2060. For 2020, we increased the mean temperature by 1°C and started the CO2 concentration at 410 ppm. For 2060, we increased temperature by 2°C and started the CO2 concentration at 550 ppm. Without changing agriculture technology, we find that compared to the control run, geoengineering with the G2 scenario starting in 2020 or 2060 would both moderately increase rice and winter wheat production due to the CO2 fertilization effect, but the increasing rates are different. However, as a C4 crop, without a significant CO2 fertilization effect, maize production would decrease slightly because of regional drought. Compared to the reference run, the three crops all have less heat stress in southern China and their yields increase, but in northern China cooler

  9. YouTube Fridays: Engaging the Net Generation in 5 Minutes a Week

    ERIC Educational Resources Information Center

    Liberatore, Matthew W.

    2010-01-01

    YouTube Fridays is a teaching tool that devotes the first five minutes of class each Friday to a YouTube video related to the course. Students select the videos, which expand the class's educational content in courses such as thermodynamics and material and energy balances. From assessments of two pilot studies using YouTube Fridays in Chemical…

  10. Exploring efficiency of sea spray geo-engineering

    NASA Astrophysics Data System (ADS)

    Pringle, K.; Carslaw, K.; Fan, T.; Mann, G.; Hill, A.; Stier, P.; Zhang, K.

    2012-04-01

    Artificially increasing the albedo of marine clouds by the mechanical emission of sea spray has been proposed as a possible geoengineering technique to slow the warming attributed to anthropogenic greenhouse gases. For the injected sea spray to cause a net cooling, the additional aerosol must result in an increase in cloud droplet number. In this study we use a physically based parameterisation of aerosol activation to quantify cloud drop number (CDN) changes over the entire parameter space of updraft speed and properties of the injected and background aerosol. We suggest criteria for when geoengineering may be an effective strategy and also identify conditions where additional aerosol will have a negligible effect or act to decrease CDN. Undesirable decreases in CDN occur when particles are injected into clouds in environments where the number concentration of background accumulation mode aerosol is > 200 cm-3. The effect is particularly strong when (i) the in-cloud updraft velocity is low (< 0.2 ms-1); and (ii) the number concentration of the additional aerosol is low (< 200 cm-3). A large increase in CDN is achieved when the converse it true. After using the box model data to identify optimum conditions, we then assess the potential of sea spray geo-engineering on a global scale. Global fields of aerosol number, natural and geo-engineered CDN (derived in an idealised framework) from three aerosol models are presented. We find that there is considerable diversity in the calculated efficiency of geo-engineering between the three models which arises from the diversity in the simulated background aerosol distribution.

  11. We Don't Need a "Geoengineering" Research Program

    NASA Astrophysics Data System (ADS)

    Caldeira, K.

    2011-12-01

    Most approaches commonly labeled as 'geoengineering' can be divided into two categories: approaches that attempt to reduce the change in atmospheric composition caused by anthropogenic emissions (commonly labeled CDR, for Carbon Dioxide Removal), and approaches that attempt to reduce the change in climate caused by changes in atmospheric composition (commonly labeled SRM, for Sunlight Reflection Methods or Solar Radiation Management). CDR is relatively uncontroversial (apart from ocean fertilization), and the primary issues are typically cost, effectiveness, local environmental consequences, and verification. In contrast, SRM has provoked much controversy, because large-scale SRM deployments necessarily would affect everyone on this planet. Several proposals have been tabled for SRM-specific or geoengineering-specific research and governance structures, treating SRM or geoengineering research as a thing apart. We should instead view CDR and SRM research as part of a broader continuum of activities aimed at understanding Earth system dynamics and reducing risks associated with climate change. The scope of existing research efforts should be broadened so that CDR and SRM approaches are, at this stage in development, treated as an extension of what we are already doing. What is 'geoengineering research'? A primary need at this time is for expansion of scope of and funding for existing climate-related research efforts. For examples: Scientists studying the role of aerosols in clouds or stratospheric processes can expand the domain of concern to consider effects of intentionally introduced aerosols (and not just natural aerosols and aerosols we introduce as a byproduct of civilization's normal functioning). Scientists studying effects of land-surface change on global and regional climates can expand the domain of concern beyond inadvertent effects to consider effects of land-surface changes undertaken with the intent to affect these climates. Research programs aimed at

  12. Impacts of Geoengineering and Nuclear War on Chinese Agriculture

    NASA Astrophysics Data System (ADS)

    Xia, L.; Robock, A.

    2011-12-01

    Climate is one of the most important factors determining crop yields and world food supplies. To be well prepared for possible futures, it is necessary to study yield changes of major crops under different climate scenarios. Here we consider two situations: stratospheric sulfate geoengineering and nuclear war. Although we certainly do not advocate either scenario, we cannot exclude the possibilities: if global warming is getting worse, we might have to deliberately manipulate global temperature; if nuclear weapons still exist, we might face a nuclear war catastrophe. Since in both scenarios there would be reductions of temperature, precipitation, and insolation, which are three controlling factors on crop growth, it is important to study food supply changes under the two cases. We conducted our simulations for China, because it has the highest population and crop production in the world and it is under the strong influence of the summer monsoon, which would be altered in geoengineering and nuclear war scenarios. To examine the effects of climate changes induced by geoengineering and nuclear war on Chinese agriculture, we use the DSSAT crop model. We first evaluate the model by forcing it with daily weather data and management practices for the period 1978-2008 for all the provinces in China, and compare the results to observations of the yields of major crops in China (middle season rice, winter wheat, and maize). Then we perturbed observed weather data using climate anomalies for geoengineering and nuclear war simulations using NASA GISS ModelE. For stratospheric geoengineering, we consider the injection of 5 Tg SO2 per year into the tropical lower stratosphere. For the nuclear war scenario, we consider the effects of 5 Tg of soot that could be injected into the upper troposphere by a war between India and Pakistan using only 100 Hiroshima-size atomic bombs dropped on cities. We perturbed each year of the 31-year climate record with anomalies from each year of

  13. Sulphate Geoengineering in the UT/LS: Some Relevant Processes

    NASA Astrophysics Data System (ADS)

    Tuck, A. F.; Donaldson, D. J.; Hitchman, M. H.; Richard, E. C.; Tervahattu, H.; Vaida, V.; Wilson, J. C.

    2008-12-01

    We consider the potential effects of meteorological dynamics, the physics and chemistry of aerosols and the photodissociation of sulphuric acid upon the posited maintenance of a 'parasol' of geoengineered sulphate aerosol in the lower stratosphere. Specific observational and experimental results include the spread of tungsten-185 from the Hardtack series of nuclear weapon tests in 1958, satellite observations of the spread of volcanic eruptions, tracer and water profiles in the tropical UT/LS, the organic coating of surfactants on aerosols, the observed distributions of aerosols and the overtone driven photodissociation of sulphuric acid in the stratosphere. A few implications for the logistics of any possible future geoengineering injection are considered briefly. The uncertainties arising from the analysis subtract significantly from the predictability of any supposed amelioration of the effects of global warming from continued increases in carbon dioxide from fossil fuel combustion.

  14. Tackling regional climate change by leaf albedo bio-geoengineering.

    PubMed

    Ridgwell, Andy; Singarayer, Joy S; Hetherington, Alistair M; Valdes, Paul J

    2009-01-27

    The likelihood that continuing greenhouse-gas emissions will lead to an unmanageable degree of climate change has stimulated the search for planetary-scale technological solutions for reducing global warming ("geoengineering"), typically characterized by the necessity for costly new infrastructures and industries. We suggest that the existing global infrastructure associated with arable agriculture can help, given that crop plants exert an important influence over the climatic energy budget because of differences in their albedo (solar reflectivity) compared to soils and to natural vegetation. Specifically, we propose a "bio-geoengineering" approach to mitigate surface warming, in which crop varieties having specific leaf glossiness and/or canopy morphological traits are specifically chosen to maximize solar reflectivity. We quantify this by modifying the canopy albedo of vegetation in prescribed cropland areas in a global-climate model, and thereby estimate the near-term potential for bio-geoengineering to be a summertime cooling of more than 1 degrees C throughout much of central North America and midlatitude Eurasia, equivalent to seasonally offsetting approximately one-fifth of regional warming due to doubling of atmospheric CO(2). Ultimately, genetic modification of plant leaf waxes or canopy structure could achieve greater temperature reductions, although better characterization of existing intraspecies variability is needed first. PMID:19147356

  15. Microphysical simulations of sulfur burdens from stratospheric sulfur geoengineering

    NASA Astrophysics Data System (ADS)

    English, J. M.; Toon, O. B.; Mills, M. J.

    2012-05-01

    Recent microphysical studies suggest that geoengineering by continuous stratospheric injection of SO2 gas may be limited by the growth of the aerosols. We study the efficacy of SO2, H2SO4 and aerosol injections on aerosol mass and optical depth using a three-dimensional general circulation model with sulfur chemistry and sectional aerosol microphysics (WACCM/CARMA). We find increasing injection rates of SO2 in a narrow band around the equator to have limited efficacy while broadening the injecting zone as well as injecting particles instead of SO2 gas increases the sulfate burden for a given injection rate, in agreement with previous work. We find that injecting H2SO4 gas instead of SO2 does not discernibly alter sulfate size or mass, in contrast with a previous study using a plume model with a microphysical model. However, the physics and chemistry in aircraft plumes, which are smaller than climate model grid cells, need to be more carefully considered. We also find significant perturbations to tropospheric aerosol for all injections studied, particularly in the upper troposphere and near the poles, where sulfate burden increases by up to 100 times. This enhanced burden could have implications for tropospheric radiative forcing and chemistry. These results highlight the need to mitigate greenhouse gas emissions rather than attempt to cool the planet through geoengineering, and to further study geoengineering before it can be seriously considered as a climate intervention option.

  16. Climate Curriculum Modules on Volcanic Eruptions, Geoengineering, and Nuclear Winter

    NASA Astrophysics Data System (ADS)

    Robock, A.

    2014-12-01

    To support a climate dynamics multidisciplinary curriculum for graduate and senior university students, I will describe on-line modules on volcanic eruptions and climate, geoengineering, and nuclear winter. Each of these topics involves aerosols in the stratosphere and the response of the climate system, but each is distinct, and each is evolving as more research becomes available. As reported for the first time in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, volcanic eruptions are a natural analog for the climate impacts of potential anthropogenic aerosol injections into the stratosphere, either sulfates from potential attempts to cool the climate to counteract global warming, or smoke that would be produced from fires in cities and industrial targets in a nuclear war. The volcanic eruptions module would stand alone, and would also serve as a prerequisite for each of the other two modules, which could be taught independently of each other. Each module includes consideration of the physical climate system as well as impacts of the resulting climate change. Geoengineering includes both solar radiation management and carbon dioxide reduction. The geoengineering and nuclear winter modules also include consideration of policy and governance issues. Each module includes a slide set for use in lecturing, links to related resources, and student exercises. The modules will be regularly updated.

  17. An overview of geoengineering of climate using stratospheric sulphate aerosols

    SciTech Connect

    Rasch, Philip J.; Tilmes, S.; Turco, Richard P.; Robock, Alan; Oman, Luke; Chen, Chih-Chieh; Stenchikov, Georgiy; Garcia, Rolando R.

    2010-01-01

    We provide an overview of geoengineering by stratospheric sulphate aerosols. The state of understanding about this topic as of early 2008 is reviewed, summarizing the past 30 years of work in the area, highlighting some very recent studies using climate models, and discussing methods used to deliver sulphur species to the stratosphere. The studies reviewed here suggest that sulphate aerosols can counteract the globally averaged temperature increase associated with increasing greenhouse gases, and reduce changes to some other components of the Earth system. There are likely to be remaining regional climate changes after geoengineering, with some regions experiencing significant changes in temperature or precipitation. The aerosols also serve as surfaces for heterogeneous chemistry resulting in increased ozone depletion. The delivery of sulphur species to the stratosphere in a way that will produce particles of the right size is shown to be a complex and potentially very difficult task. Two simple delivery scenarios are explored, but similar exercises will be needed for other suggested delivery mechanisms. While the introduction of the geoengineering source of sulphate aerosol will perturb the sulphur cycle of the stratosphere signicantly, it is a small perturbation to the total (stratosphere and troposphere) sulphur cycle. The geoengineering source would thus be a small contributor to the total global source of ‘acid rain’ that could be compensated for through improved pollution control of anthropogenic tropospheric sources. Some areas of research remain unexplored. Although ozone may be depleted, with a consequent increase to solar ultraviolet-B (UVB) energy reaching the surface and a potential impact on health and biological populations, the aerosols will also scatter and attenuate this part of the energy spectrum, and this may compensate the UVB enhancement associated with ozone depletion. The aerosol will also change the ratio of diffuse to direct energy

  18. The Many Problems with Geoengineering Using Stratospheric Aerosols

    NASA Astrophysics Data System (ADS)

    Robock, Alan

    2009-05-01

    In response to the global warming problem, there has been a recent renewed call for geoengineering ``solutions'' involving injecting particles into the stratosphere or blocking sunlight with satellites between the Sun and Earth. 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. In this talk, I consider the suggestion to create an artificial stratospheric aerosol layer. No systems to conduct geoengineering now exist, but a comparison of different proposed stratospheric injection schemes, airplanes, balloons, artillery, and a space elevator, shows that using airplanes would not be that expensive. We simulated 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 simulated the injection of SO2 and the model converts it to sulfate aerosols, transports them and removes them through dry and wet deposition, and calculates the climate response to the radiative forcing from the aerosols. We conducted 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 found that if there were a way to continuously inject SO2 into the lower stratosphere, it would produce global cooling. Acid deposition from the sulfate would not be enough to disturb most ecosystems. 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. But both tropical and Arctic SO2 injection would disrupt the Asian and African summer monsoons, reducing precipitation to the food supply

  19. An overview of geoengineering of climate using stratospheric sulphate aerosols.

    PubMed

    Rasch, Philip J; Tilmes, Simone; Turco, Richard P; Robock, Alan; Oman, Luke; Chen, Chih-Chieh; Stenchikov, Georgiy L; Garcia, Rolando R

    2008-11-13

    We provide an overview of geoengineering by stratospheric sulphate aerosols. The state of understanding about this topic as of early 2008 is reviewed, summarizing the past 30 years of work in the area, highlighting some very recent studies using climate models, and discussing methods used to deliver sulphur species to the stratosphere. The studies reviewed here suggest that sulphate aerosols can counteract the globally averaged temperature increase associated with increasing greenhouse gases, and reduce changes to some other components of the Earth system. There are likely to be remaining regional climate changes after geoengineering, with some regions experiencing significant changes in temperature or precipitation. The aerosols also serve as surfaces for heterogeneous chemistry resulting in increased ozone depletion. The delivery of sulphur species to the stratosphere in a way that will produce particles of the right size is shown to be a complex and potentially very difficult task. Two simple delivery scenarios are explored, but similar exercises will be needed for other suggested delivery mechanisms. While the introduction of the geoengineering source of sulphate aerosol will perturb the sulphur cycle of the stratosphere signicantly, it is a small perturbation to the total (stratosphere and troposphere) sulphur cycle. The geoengineering source would thus be a small contributor to the total global source of 'acid rain' that could be compensated for through improved pollution control of anthropogenic tropospheric sources. Some areas of research remain unexplored. Although ozone may be depleted, with a consequent increase to solar ultraviolet-B (UVB) energy reaching the surface and a potential impact on health and biological populations, the aerosols will also scatter and attenuate this part of the energy spectrum, and this may compensate the UVB enhancement associated with ozone depletion. The aerosol will also change the ratio of diffuse to direct energy

  20. The impact of geoengineering on vegetation in experiment G1 of the Geoengineering Model Intercomparison Project

    NASA Astrophysics Data System (ADS)

    Irvine, Peter; Glienke, Susanne; Lawrence, Mark

    2015-04-01

    Solar Radiation Management (SRM) has been proposed as a means to partly counteract global warming. The Geoengineering Model Intercomparison Project (GeoMIP) simulated the climate consequences of a number of SRM techniques, but the effects on vegetation have not yet been thoroughly studied. Here, the vegetation response to the idealized GeoMIP G1 experiment is analyzed, in which a reduction of the solar constant counterbalances the radiative effects of quadrupled atmospheric CO2 concentrations; the results from eight fully coupled earth system models (ESMs) are included. For most models and regions, changes in net primary productivity (NPP) are dominated by the increase in CO2, via the CO2 fertilization effect. As SRM will lower temperatures, in high latitudes this will reverse gains in NPP from the lifting of temperature limitations. In low latitudes this cooling relative to the 4xCO2 simulation decreases plant respiration whilst having little effect on gross primary productivity, increasing NPP. Despite reductions in precipitation in most regions in response to SRM, runoff and NPP increase in many regions including those previously highlighted as potentially being at risk of drought under SRM. This is due to simultaneous reductions in evaporation and increases in water use efficiency by plants due to higher CO2 concentrations. The relative differences between models in the vegetation response are substantially larger than the differences in their climate responses. The largest differences between models are for those with and without a nitrogen-cycle, with a much smaller CO2 fertilization effect for the former. These results suggest that until key vegetation processes are integrated into ESM predictions, the vegetation response to SRM will remain highly uncertain.

  1. Microphysical simulations of sulfur burdens from stratospheric sulfur geoengineering

    NASA Astrophysics Data System (ADS)

    English, J. M.; Toon, O. B.; Mills, M. J.

    2012-01-01

    Recent microphysical studies suggest that geoengineering by continuous stratospheric injection of SO2 gas may be limited by the growth of the aerosols. We study the efficacy of SO2, H2SO4 and aerosol injections on aerosol mass and optical depth using a three-dimensional general circulation model with sulfur chemistry and sectional aerosol microphysics (WACCM/CARMA). We find increasing injection rates of SO2 in a narrow band around the equator to have limited efficacy while broadening the injecting zone as well as injecting particles instead of SO2 gas increases the sulfate burden for a given injection rate, in agreement with previous work. We find that injecting H2SO4 gas instead of SO2 does not discernibly alter sulfate size or mass, in contrast with a previous study using a plume model with a microphysical model. However, the physics and chemistry in aircraft plumes, which are smaller than climate model grid cells, need to be more carefully considered. We find equatorial injections increase aerosol optical depth in the Northern Hemisphere more than the Southern Hemisphere, potentially inducing regional climate changes. We also find significant perturbations to tropospheric aerosol for all injections studied, particularly in the upper troposphere and near the poles, where sulfate burden increases by up to 100 times. This enhanced burden could have implications for tropospheric radiative forcing and chemistry. These results highlight the need to mitigate greenhouse gas emissions through means other than geoengineering, and to further study geoengineering before it can be seriously considered as a climate intervention option.

  2. Applied high resolution geophysical methods: Offshore geoengineering hazards

    SciTech Connect

    Trabant, P.K.

    1984-01-01

    This book is an examination of the purpose, methodology, equipment, and data interpretation of high-resolution geophysical methods, which are used to assess geological and manmade engineering hazards at offshore construction locations. It is a state-of-the-art review. Contents: 1. Introduction. 2. Maring geophysics, an overview. 3. Marine geotechnique, an overview. 4. Echo sounders. 5. Side scan sonar. 6. Subbottom profilers. 7. Seismic sources. 8. Single-channel seismic reflection systems. 9. Multifold acquisition and digital processing. 10. Marine magnetometers. 11. Marine geoengineering hazards. 12. Survey organization, navigation, and future developments. Appendix. Glossary. References. Index.

  3. Impacts of volcanic eruptions and geoengineering on Arctic climate

    NASA Astrophysics Data System (ADS)

    Berdahl, Mira

    Stratospheric aerosols can produce large radiative forcing and climate response, often amplified in the Arctic. Here I study the Arctic response to natural (volcanic eruptions) and potential anthropogenic (geoengineering) stratospheric sulfate aerosols. I use a regional climate model and global climate model output from two modeling intercomparison projects. First, I investigate the relative impacts of changes in radiation and advection on snow extent over Baffin Island with the Weather Research and Forecasting model. Model results show it is possible to suddenly lower the snowline by amounts comparable to those seen during the Little Ice Age with an average temperature decrease of --3.9 +/- 1.1 K from present. Further, sea ice expansion following large volcanic eruptions would have significant affects on inland temperatures, especially in the fall. Next, I analyze Last Millennium simulations from the Paleoclimate Modeling Intercomparison Project 3 to assess whether state-of-the-art global climate models produce sudden changes and persistence of cold conditions after large volcanic eruptions as inferred by geological records and previous climate modeling. North Atlantic sea ice and Baffin Island snow cover showed large-scale expansion in the simulations, but none of the models produced significant centennial-scale effects. Warm Baffin Island summer climates stunt snow expansion in some models completely, and model topography misses the critical elevations that could sustain snow on the island. This has critical consequences for ice and snow formation and persistence in regions such as the Arctic where temperatures are near freezing and small temperature changes affect the state of water. Finally, I analyze output from the Geoengineering Modeling Intercomparison Project to examine whether geoengineering by injection of sulfate aerosols into the lower stratosphere prevents the demise of minimum annual sea ice extent, or slows spring snow cover loss. Despite

  4. Sea spray geoengineering experiments in the geoengineering model intercomparison project (GeoMIP): Experimental design and preliminary results

    NASA Astrophysics Data System (ADS)

    Kravitz, Ben; Forster, Piers M.; Jones, Andy; Robock, Alan; Alterskjær, Kari; Boucher, Olivier; Jenkins, Annabel K. L.; Korhonen, Hannele; Kristjánsson, Jón Egill; Muri, Helene; Niemeier, Ulrike; Partanen, Antti-Ilari; Rasch, Philip J.; Wang, Hailong; Watanabe, Shingo

    2013-10-01

    cloud brightening through sea spray injection has been proposed as a method of temporarily alleviating some of the impacts of anthropogenic climate change, as part of a set of technologies called geoengineering. We outline here a proposal for three coordinated climate modeling experiments to test aspects of sea spray geoengineering, to be conducted under the auspices of the Geoengineering Model Intercomparison Project (GeoMIP). The first, highly idealized, experiment (G1ocean-albedo) involves a uniform increase in ocean albedo to offset an instantaneous quadrupling of CO2 concentrations from preindustrial levels. Results from a single climate model show an increased land-sea temperature contrast, Arctic warming, and large shifts in annual mean precipitation patterns. The second experiment (G4cdnc) involves increasing cloud droplet number concentration in all low-level marine clouds to offset some of the radiative forcing of an RCP4.5 scenario. This experiment will test the robustness of models in simulating geographically heterogeneous radiative flux changes and their effects on climate. The third experiment (G4sea-salt) involves injection of sea spray aerosols into the marine boundary layer between 30°S and 30°N to offset 2 W m-2 of the effective radiative forcing of an RCP4.5 scenario. A single model study shows that the induced effective radiative forcing is largely confined to the latitudes in which injection occurs. In this single model simulation, the forcing due to aerosol-radiation interactions is stronger than the forcing due to aerosol-cloud interactions.

  5. Sea spray geoengineering can reduce ocean net primary productivity and carbon uptake

    NASA Astrophysics Data System (ADS)

    Partanen, Antti-Ilari; Keller, David; Korhonen, Hannele; Matthews, Damon

    2016-04-01

    Sea spray geoengineering or marine cloud brightening is one of the proposed methods to deliberately increase planetary albedo and thus counteract climate change. Previous studies have shown that it has potential to significantly alter the global energy balance and reduce impacts on temperature and precipitation. However, its effects on ecosystems have received considerably less attention. Our goal is to assess the effects of sea spray geoengineering on marine biological productivity and global carbon cycle. We use the University of Victoria Earth System Climate Model (UVic ESCM) to simulate the effects of prescribed aerosol forcing from previous simulations with the aerosol-climate model ECHAM-HAMMOZ. In our baseline simulation (GEO), forcing from geoengineering was applied over three persistent stratocumulus regions off the coasts of North America, South America, and South Africa. The global mean forcing was -1 W m‑2. Other forcings and emissions were set according to the RCP4.5 scenario. The control run (CTRL) was identical to GEO except that no geoengineering was present. As a more extreme case, we simulated a scenario where forcing from geoengineering was applied over all ocean area (GEO-ALL) giving a global mean forcing of -4.9 W m‑2. Geoengineering decreased the global total ocean net primary productivity (NPP) during the first decades, but the effect was insignificant by the end of the 21st century. The decrease was caused by decreased temperature of the ocean and climate system in general, not by the decrease in available sunlight as might have been expected. This was demonstrated by two sensitivity simulations where geoengineering was affecting only either temperature or the light available to marine ecosystems. The simulation GEO-ALL behaves in a different way than GEO: ocean NPP was lower than that in CTRL for the first three decades of geoengineering as in GEO, but then NPP increased over the level in CTRL for the remaining of the simulation. In

  6. Geoengineering Vision-Application for Space Solar Power

    NASA Astrophysics Data System (ADS)

    Eastlund, B. J.; Jenkins, L. M.

    2004-12-01

    The continued extreme use of fossil fuels to meet world energy needs is putting the Earth at risk for significant climate change. In an uncontrolled experiment, the buildup of carbon dioxide and other greenhouse gases is apparently affecting the Earth's climate. The global climate is warming and severe storms such as hurricanes and tornadoes are getting worse. Alternatives to fossil fuels may reduce the addition of carbon dioxide to the atmosphere. Space Solar Power, from orbiting satellites, provides an option for clean, renewable energy that will reduce the pressure on the Earth's environmental system. Uncertainty in the cost of commercial power from space has been the principal issue inhibiting investment support by the power companies. Geoengineering is defined as the use of technology to interact with the global environment. A Solar Power Satellite represents a capability for considering geoengineering concepts. The Thunderstorm Solar Power Satellite (TSPS) is a concept for interacting with thunderstorms to prevent formation of tornadoes. Before weather modification can be safely attempted, the fine structure of thunderstorms must be computer simulated and related to tornadogenesis. TSPS benefits are saving lives and reducing property. These benefits are not as sensitive to the system economics as the commercial solar power satellite and can be used to justify government investment in space solar power. The TSPS can develop and demonstrate the technology and operations critical to understanding the cost of space solar power. Consequently, there is no direct competition with fossil fuel based power supplies until SSP technology and operations have been demonstrated.

  7. Acid Deposition From Stratospheric Geoengineering With Sulfate Aerosols

    NASA Astrophysics Data System (ADS)

    Kravitz, B.; Robock, A.; Oman, L.; Stenchikov, G.

    2008-12-01

    We used a general circulation model of the Earth's climate to conduct geoengineering experiments involving stratospheric injection of sulfur dioxide [Robock et al., 2008] and analyzed the resulting deposition of sulfate. When sulfur is injected into the tropical or Arctic stratosphere, the main additional surface deposition occurs in midlatitude bands, because of strong cross-tropopause flux in the jet stream regions, and there are some larger local increases, specifically in Northern Canada and the Western Pacific Ocean. We used critical load studies to determine the effects of this increase in acid deposition on terrestrial ecosystems. For annual injection of 5 Tg of SO2 into the tropical stratosphere or 3 Tg of SO2 into the Arctic stratosphere, the additional surface sulfate deposition is not enough to negatively impact most ecosystems. Robock, Alan, Luke Oman, and Georgiy Stenchikov (2008), Regional climate responses to geoengineering with tropical and Arctic SO2 injections. J. Geophys. Res., 113, D16101, doi:10.1029/2008JD010050.

  8. Solar geoengineering using solid aerosol in the stratosphere

    NASA Astrophysics Data System (ADS)

    Weisenstein, D. K.; Keith, D. W.; Dykema, J. A.

    2015-10-01

    Solid aerosol particles have long been proposed as an alternative to sulfate aerosols for solar geoengineering. Any solid aerosol introduced into the stratosphere would be subject to coagulation with itself, producing fractal aggregates, and with the natural sulfate aerosol, producing liquid-coated solids. Solid aerosols that are coated with sulfate and/or have formed aggregates may have very different scattering properties and chemical behavior than uncoated non-aggregated monomers do. We use a two-dimensional (2-D) chemistry-transport-aerosol model to capture the dynamics of interacting solid and liquid aerosols in the stratosphere. As an example, we apply the model to the possible use of alumina and diamond particles for solar geoengineering. For 240 nm radius alumina particles, for example, an injection rate of 4 Tg yr-1 produces a global-average shortwave radiative forcing of -1.2 W m-2 and minimal self-coagulation of alumina although almost all alumina outside the tropics is coated with sulfate. For the same radiative forcing, these solid aerosols can produce less ozone loss, less stratospheric heating, and less forward scattering than sulfate aerosols do. Our results suggest that appropriately sized alumina, diamond or similar high-index particles may have less severe technology-specific risks than sulfate aerosols do. These results, particularly the ozone response, are subject to large uncertainties due to the limited data on the rate constants of reactions on the dry surfaces.

  9. Deliberative Mapping of options for tackling climate change: Citizens and specialists 'open up' appraisal of geoengineering.

    PubMed

    Bellamy, Rob; Chilvers, Jason; Vaughan, Naomi E

    2016-04-01

    Appraisals of deliberate, large-scale interventions in the earth's climate system, known collectively as 'geoengineering', have largely taken the form of narrowly framed and exclusive expert analyses that prematurely 'close down' upon particular proposals. Here, we present the findings from the first 'upstream' appraisal of geoengineering to deliberately 'open up' to a broader diversity of framings, knowledges and future pathways. We report on the citizen strand of an innovative analytic-deliberative participatory appraisal process called Deliberative Mapping. A select but diverse group of sociodemographically representative citizens from Norfolk (United Kingdom) were engaged in a deliberative multi-criteria appraisal of geoengineering proposals relative to other options for tackling climate change, in parallel to symmetrical appraisals by diverse experts and stakeholders. Despite seeking to map divergent perspectives, a remarkably consistent view of option performance emerged across both the citizens' and the specialists' deliberations, where geoengineering proposals were outperformed by mitigation alternatives. PMID:25224904

  10. Overview of the Integrated Assessment of Geoengineering Proposals (IAGP), UK research project.

    NASA Astrophysics Data System (ADS)

    Forster, P.

    2014-12-01

    Integrated Assessment of Geoengineering Proposals (IAGP, www.iagp.ac.uk ) is a multidisciplinary research project involving seven UK institutions. This four year research project (completing in Feb 2015) has bought together a broad range of expertise, from climate modelling to philosophy and engineering to public perceptions to conduct an objective, policy-relevant assessment of geoengineering. This paper will present an overview of our major research findings, concentrating on aspects related to solar radiation management. Findings of our five inter-linked programmes will be presented:1. Framework development - developing a methodology for comparing across different technologies. 2. Engaging with publics and stakeholders - illustrating how public and stakeholder views have informed the development of the framework and the way we assess geoengineering. 3. Using climate modelling to evaluate geoengineering technologies - experiments for several different SRM techniques are compared within the HadGEM2 climate model. These include aerosol injection into the stratosphere as well as ocean and land albedo changes. 4. Earth climate controllability - examining how techniques from control engineering can be applied to geoengineering and the implications for decision and policy-making. 5. Critical reflection on the development of our research agenda and views. These five strands of research will be bought together to illustrate responsible innovation of geoengineering research.

  11. A risk-based framework for assessing the effectiveness of stratospheric aerosol geoengineering.

    PubMed

    Ferraro, Angus J; Charlton-Perez, Andrew J; Highwood, Eleanor J

    2014-01-01

    Geoengineering by stratospheric aerosol injection has been proposed as a policy response to warming from human emissions of greenhouse gases, but it may produce unequal regional impacts. We present a simple, intuitive risk-based framework for classifying these impacts according to whether geoengineering increases or decreases the risk of substantial climate change, with further classification by the level of existing risk from climate change from increasing carbon dioxide concentrations. This framework is applied to two climate model simulations of geoengineering counterbalancing the surface warming produced by a quadrupling of carbon dioxide concentrations, with one using a layer of sulphate aerosol in the lower stratosphere, and the other a reduction in total solar irradiance. The solar dimming model simulation shows less regional inequality of impacts compared with the aerosol geoengineering simulation. In the solar dimming simulation, 10% of the Earth's surface area, containing 10% of its population and 11% of its gross domestic product, experiences greater risk of substantial precipitation changes under geoengineering than under enhanced carbon dioxide concentrations. In the aerosol geoengineering simulation the increased risk of substantial precipitation change is experienced by 42% of Earth's surface area, containing 36% of its population and 60% of its gross domestic product. PMID:24533155

  12. Deliberating stratospheric aerosols for climate geoengineering and the SPICE project

    NASA Astrophysics Data System (ADS)

    Pidgeon, Nick; Parkhill, Karen; Corner, Adam; Vaughan, Naomi

    2013-05-01

    Increasing concerns about the narrowing window for averting dangerous climate change have prompted calls for research into geoengineering, alongside dialogue with the public regarding this as a possible response. We report results of the first public engagement study to explore the ethics and acceptability of stratospheric aerosol technology and a proposed field trial (the Stratospheric Particle Injection for Climate Engineering (SPICE) 'pipe and balloon' test bed) of components for an aerosol deployment mechanism. Although almost all of our participants were willing to allow the field trial to proceed, very few were comfortable with using stratospheric aerosols. This Perspective also discusses how these findings were used in a responsible innovation process for the SPICE project initiated by the UK's research councils.

  13. Impacts of sea spray geoengineering on ocean biogeochemistry

    NASA Astrophysics Data System (ADS)

    Partanen, Antti-Ilari; Keller, David P.; Korhonen, Hannele; Matthews, H. Damon

    2016-07-01

    We used an Earth system model of intermediate complexity to study the effects of Solar Radiation Management (SRM) by sea spray geoengineering on ocean biogeochemistry. SRM slightly decreased global ocean net primary productivity (NPP) relative to the control run. The lower temperatures in the SRM run decreased NPP directly but also indirectly increased NPP in some regions due to changes in nutrient availability resulting from changes in ocean stratification and circulation. Reduced light availability had a minor effect on global total NPP but a major regional effect near the nutrient-rich upwelling region off the coast of Peru, where light availability is the main limiting factor for phytoplankton growth in our model. Unused nutrients from regions with decreased NPP also fueled NPP elsewhere. In the context of RCP4.5 simulation used here, SRM decreased ocean carbon uptake due to changes in atmospheric CO2 concentrations, seawater chemistry, NPP, temperature, and ocean circulation.

  14. Geoengineering potential of artificially enhanced silicate weathering of olivine.

    PubMed

    Köhler, Peter; Hartmann, Jens; Wolf-Gladrow, Dieter A

    2010-11-23

    Geoengineering is a proposed action to manipulate Earth's climate in order to counteract global warming from anthropogenic greenhouse gas emissions. We investigate the potential of a specific geoengineering technique, carbon sequestration by artificially enhanced silicate weathering via the dissolution of olivine. This approach would not only operate against rising temperatures but would also oppose ocean acidification, because it influences the global climate via the carbon cycle. If important details of the marine chemistry are taken into consideration, a new mass ratio of CO(2) sequestration per olivine dissolution of about 1 is achieved, 20% smaller than previously assumed. We calculate that this approach has the potential to sequestrate up to 1 Pg of C per year directly, if olivine is distributed as fine powder over land areas of the humid tropics, but this rate is limited by the saturation concentration of silicic acid. In our calculations for the Amazon and Congo river catchments, a maximum annual dissolution of 1.8 and 0.4 Pg of olivine seems possible, corresponding to the sequestration of 0.5 and 0.1 Pg of C per year, but these upper limit sequestration rates come at the environmental cost of pH values in the rivers rising to 8.2. Open water dissolution of fine-grained olivine and an enhancement of the biological pump by the rising riverine input of silicic acid might increase our estimate of the carbon sequestration, but additional research is needed here. We finally calculate with a carbon cycle model the consequences of sequestration rates of 1-5 Pg of C per year for the 21st century by this technique. PMID:21059941

  15. Geoengineering potential of artificially enhanced silicate weathering of olivine

    PubMed Central

    Köhler, Peter; Hartmann, Jens; Wolf-Gladrow, Dieter A.

    2010-01-01

    Geoengineering is a proposed action to manipulate Earth’s climate in order to counteract global warming from anthropogenic greenhouse gas emissions. We investigate the potential of a specific geoengineering technique, carbon sequestration by artificially enhanced silicate weathering via the dissolution of olivine. This approach would not only operate against rising temperatures but would also oppose ocean acidification, because it influences the global climate via the carbon cycle. If important details of the marine chemistry are taken into consideration, a new mass ratio of CO2 sequestration per olivine dissolution of about 1 is achieved, 20% smaller than previously assumed. We calculate that this approach has the potential to sequestrate up to 1 Pg of C per year directly, if olivine is distributed as fine powder over land areas of the humid tropics, but this rate is limited by the saturation concentration of silicic acid. In our calculations for the Amazon and Congo river catchments, a maximum annual dissolution of 1.8 and 0.4 Pg of olivine seems possible, corresponding to the sequestration of 0.5 and 0.1 Pg of C per year, but these upper limit sequestration rates come at the environmental cost of pH values in the rivers rising to 8.2. Open water dissolution of fine-grained olivine and an enhancement of the biological pump by the rising riverine input of silicic acid might increase our estimate of the carbon sequestration, but additional research is needed here. We finally calculate with a carbon cycle model the consequences of sequestration rates of 1–5 Pg of C per year for the 21st century by this technique. PMID:21059941

  16. Dyson Dots & Geoengineering: The Killer App Ad Astra

    NASA Astrophysics Data System (ADS)

    Kennedy, R. G.; Hughes, Eric; Roy, Kenneth I.; Fields, David E.

    No study of coping with climate change is complete without considering geoengineering. A "Dyson Dot" is one or more large (area ~700 K km2, >200 megatonne) lightsail(s) in a radiation-levitated non-Keplerian orbit(s) just sunward of the Sun-Earth Lagrange-1 point. The purpose of this syncretic concept is twofold: (I) As a parasol, it would reduce insolation on Earth by at least one-quarter of a percent (-3.4 W m-2), same as what caused 1.5°C drop during the "Little Ice Age" (~1550-1850) and same as the IPCC Third Report's mid-range value for global warming by 2050. The parasol transforms the "solar constant" to a controlled solar variable. (II) Hosting a ~50K km2 photovoltaic power station on its sunny side and relaying beamed power via maser to rectennas on a circumpolar Dymaxion grid, the system could displace over 300 EJ/a (~100 trillion kWh/yr) of fossil-fired power (total global demand for electricity forecast by 2050), while providing USD trillions in revenue from cheap clean energy sales (@1-3¢/kWh) to amortize the scheme. Total system efficiency compares favorably to automobiles; total system power density is comparable to nuclear power. This approach -- self-funding, "pay-as-you-go", minimally intrusive, scalable, complementary with a portfolio of other measures and above all reversible is not precluded by international treaty. Indeed geoengineering may be the best "killer app" to bootstrap orbital industry and humanity ad astra, because the terawattscale product is comparable to the power required for interstellar travel. If Tellurian spacefaring civilization bootstraps its exponential growth with multi-terawatt maser beams from such lightsails, there might eventually be enough of them to have a detectable effect on Sol's apparent luminosity at certain wavelengths, as seen from far away, similar to the eponymous Dyson Sphere, hence the moniker.

  17. A Fully Coupled GCM Study of a "Geoengineered World"

    NASA Astrophysics Data System (ADS)

    Lunt, D. J.; Ridgwell, A.; Valdes, P. J.

    2007-12-01

    Several schemes have been proposed with the explicit aim of modifying the future climate of the planet as a mitigation strategy in a response to anthropogenic global warming. A selection of these, including the placing of mirrors at the Lagrange point between the Earth and the Sun, and the injection of aerosols into the stratosphere, have at their heart the goal of effectively reducing the incoming solar radiation near the top of the atmosphere, to "balance" increased surface warming due to increased greenhouse gas concentrations. However, it is likely that an exact balance of the radiative forcing would be very difficult to obtain, due to differing spatial characteristics of the solar forcing applied (greatest at the equator and least at the poles) and that of long wave absorption (more equal over all latitudes), as well as differing temporal characteristics of the radiative forcings. In this study, we model the different climate expected in a "Geoengineered World", compared to the "Preindustrial World", if both have the same global annual mean surface temperature. We use the UK Met Office GCM, HadCM3L, and carry out 5 simulations: Pre-industrial, Doubled CO2, Quadrupled CO2, and 2 simulations in which the increased CO2 is balanced in the global annual mean by a reduction in incoming solar radiation. The "strength" of mirror/aerosol required is calculated using an iterative procedure, until balance is obtained. Our results indicate significant differences between the Geoengineered World and the Preindustrial World, despite near identical global annual mean surface temperatures. In particular, we obtain relatively large differences in surface temperature over mid-latitude continental regions, in particular North America, and significant changes in upwelling on the West African tropical coast. The drying of the American Mid-West, and impacts on Africa fisheries, are likely to have significant consequences for global and local food production.

  18. Space Symposium/76

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A symposium dealing with career opportunities in the aerospace program for minorities was conducted and evaluated. The symposium was attended by students from eleven predominantly minority colleges and universities in and around Washington, D. C. and the eastern region, and from high schools in five jurisdictions of the Washington metropolitan area. Speakers included representatives of Howard University, NASA, and private industry. On display during the symposium was a NASA exhibit of moon rocks, space shuttles, a lunar module, command module, pacemaker, LANDSAT, and other items of interest.

  19. A Combined Energy and Geoengineering Optimization Model (CEAGOM) for Climate Policy Analysis

    NASA Astrophysics Data System (ADS)

    Anasis, John George

    One of the greatest challenges that will face humanity in the 21 st century is the issue of climate change brought about by emissions of greenhouse gases. Energy use is one of the primary sources of greenhouse gas emissions. However, it is also one of the most important contributors to improved human welfare over the past two centuries and will continue to be so for years to come. This quandary has led a number of researchers to suggest that geoengineering may be required in order to allow for continued use of fossil fuels while at the same time mitigating the effects of the associated greenhouse gas emissions on the global climate. The goal of this research was to develop a model that would allow decision-makers and policy analysts to assess the optimal mix of energy and geoengineering resources needed to meet global or regional energy demand at the lowest cost while accounting for appropriate emissions, greenhouse gas concentration, or temperature rise constraints. The resulting software model is called the Combined Energy and Geoengineering Optimization Model (CEAGOM). CEAGOM was then used to analyze the recently announced U.S.-China emissions agreement and to assess what the optimal global energy resource mix might be over the course of the 21 st century, including the associated potential need for geoengineering. These analyses yielded optimal mixes of energy and geoengineering resources that could be used to inform regional and global energy and climate management strategies.

  20. Stratospheric changes caused by geoengineering applications: potential repercussions and uncertainties

    NASA Astrophysics Data System (ADS)

    Kenzelmann, P.; Weisenstein, D.; Peter, T.; Luo, B. P.; Rozanov, E.; Fueglistaler, S.; Thomason, L. W.

    2009-04-01

    Anthropogenic greenhouse gas emissions tend to warm the global climate, calling for significant rapid emission reductions. As potential support measures various ideas for geoengineering are currently being discussed. The assessment of the possible manifold and as yet substantially unexplored repercussions of implementing geoengineering ideas to ameliorate climate change poses enormous challenges not least in the realm of aerosol-cloud-climate interactions. Sulphur aerosols cool the Earth's surface by reflecting short wave radiation. By increasing the amount of sulphur aerosols in the stratosphere, for example by sulphur dioxide injections, part of the anthropogenic climate warming might be compensated due to enhanced albedo. However, we are only at the beginning of understanding possible side effects. One such effect that such aerosol might have is the warming of the tropical tropopause and consequently the increase of the amount of stratospheric water vapour. Using the 2D AER Aerosol Model we calculated the aerosol distributions for yearly injections of 1, 2, 5 and 10 Mt sulphur into the lower tropical stratosphere. The results serve as input for the 3D chemistry-climate model SOCOL, which allows calculating the aerosol effect on stratospheric temperatures and chemistry. In the injection region the continuously formed sulphuric acid condensates rapidly on sulphate aerosol, which eventually grow to such extent that they sediment down to the tropical tropopause region. The growth of the aerosol particles depends on non-linear processes: the more sulphur is emitted the faster the particles grow. As a consequence for the scenario with continuous sulphur injection of totally 10 Mt per year, only 6 Mt sulphur are in the stratosphere if equilibrium is reached. According to our model calculations this amount of sulphate aerosols leads to a net surface forcing of -3.4 W/m2, which is less then expected radiative forcing by doubling of carbon dioxide concentration. Hence

  1. Optimizing stratospheric sulfur geoengineering by seasonally changing sulfur injections

    NASA Astrophysics Data System (ADS)

    Laakso, Anton; Partanen, Antti-Ilari; Kokkola, Harri; Lehtinen, Kari; Korhonen, Hannele

    2015-04-01

    Solar radiation management (SRM) by stratospheric sulfur injection has been shown to have potential in counteracting global warming if reducing of greenhouse gases has not been achieved fast enough and if climate warming will continue. Injecting large amounts of sulfate particles to the stratosphere would increase the reflectivity of the atmosphere and less sunlight would reach the surface. However, the effectivity (per injected sulphur mass unit) of this kind of geoengineering would decrease when amount of injected sulfur is increased. When sulfur concentration increases, stratospheric particles would grow to larger sizes which have larger gravitational settling velocity and which do not reflect radiation as efficiently as smaller particles. In many previous studies, sulfur has been assumed to be injected along the equator where yearly mean solar intensity is the highest and from where sulfur is spread equally to both hemispheres. However, the solar intensity will change locally during the year and sulfate has been assumed to be injected and spread to the hemisphere also during winter time, when the solar intensity is low. Thus sulfate injection could be expected to be more effective, if sulfur injection area is changed seasonally. Here we study effects of the different SRM injection scenarios by using two versions of the MPI climate models. First, aerosol spatial and temporal distributions as well as the resulting radiative properties from the SRM are defined by using the global aerosol-climate model ECHAM6.1-HAM2.2-SALSA. After that, the global and regional climate effects from different injection scenarios are predicted by using the Max Planck Institute's Earth System Model (MPI-ESM). We carried out simulations, where 8 Tg of sulfur is injected as SO2 to the stratosphere at height of 20-22 km in an area ranging over a 20 degree wide latitude band. Results show that changing the sulfur injection area seasonally would lead to similar global mean shortwave

  2. Sensitivity of Methane Lifetime and Transport to Sulfate Geoengineering

    NASA Astrophysics Data System (ADS)

    Aquila, V.; Pitari, G.; Tilmes, S.; Cionni, I.; de Luca, N.; Di Genova, G.; Iachetti, D.

    2014-12-01

    Sulfate geoengineering, made by sustained injection of SO2 in the tropical lower stratosphere, may impact the abundance of tropospheric methane through several photochemical mechanisms affecting the tropospheric OH abundance and hence the methane lifetime. Changes of the stratospheric Brewer-Dobson circulation also play a role in the upper tropospheric CH4 transport. Three mechanisms lead to lower OH concentrations and a longer CH4 lifetime: (a) solar radiation scattering increases the planetary albedo and cools the surface, with a tropospheric water vapor decrease as a response to this cooling. (b) The tropospheric UV budget is upset by the additional aerosol scattering and stratospheric ozone changes: the net effect is meridionally not uniform, with a net decrease in the tropics, thus producing less tropospheric O(1D). (c) The extra-tropical downwelling motion from the lower stratosphere tends to increase the sulfate aerosol surface area density available for heterogeneous chemical reactions in the mid-upper troposphere, thus reducing the amount of NOx and tropospheric O3 production. On the other hand, the tropical lower stratosphere is warmed by solar and planetary radiation absorption by the aerosols. The heating rates perturbation are strongly latitude dependent, producing a significant change of the pole-to-equator temperature gradient and mean zonal wind distribution, with a net increase of tropical upwelling. A stronger meridional component of the Brewer-Dobson circulation increases the extra-tropical stratosphere to troposphere transport of CH4 poorer air, resulting in less CH4 transported in the UTLS. The net effect on tropospheric OH may be positive or negative depending on the net result of different superimposed species perturbations in the UTLS, i.e. CH4 (negative), NOy and O3 (positive). Three climate-chemistry coupled models are used here to explore the above radiative, chemical and dynamical mechanisms affecting the methane lifetime (ULAQ

  3. Ninteenth Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    1985-01-01

    The proceedings of the 19th Aerospace Mechanisms Symposium are reported. Technological areas covered include space lubrication, bearings, aerodynamic devices, spacecraft/Shuttle latches, deployment, positioning, and pointing. Devices for spacecraft docking and manipulator and teleoperator mechanisms are also described.

  4. 1999 Flight Mechanics Symposium

    NASA Technical Reports Server (NTRS)

    Lynch, John P. (Editor)

    1999-01-01

    This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium held on May 18-20, 1999. Sponsored by the Guidance, Navigation and Control Center of Goddard Space Flight Center, this symposium featured technical papers on a wide range of issues related to orbit-attitude prediction, determination, and control; attitude sensor calibration; attitude determination error analysis; attitude dynamics; and orbit decay and maneuver strategy. Government, industry, and the academic community participated in the preparation and presentation of these papers.

  5. ACS Symposium Support

    SciTech Connect

    Kenneth D. Jordan

    2010-02-20

    The funds from this DOE grant were used to help cover the travel costs of five students and postdoctoral fellows who attended a symposium on 'Hydration: From Clusters to Aqueous Solutions' held at the Fall 2007 American Chemical Society Meeting in Boston, MA, August 19-23. The Symposium was sponsored by the Physical Chemistry Division, ACS. The technical program for the meeting is available at http://phys-acs.org/fall2007.html.

  6. Geo-Engineering Climate Change with Sulfate Aerosol

    NASA Astrophysics Data System (ADS)

    Rasch, P. J.; Crutzen, P. J.

    2006-12-01

    We explore the impact of injecting a precursor of sulfate aerosols into the middle atmosphere where they would act to increase the planetary albedo and thus counter some of the effects of greenhouse gase forcing. We use an atmospheric general circulation model (CAM, the Community Atmosphere Model) coupled to a slab ocean model for this study. Only physical effects are examined, that is we ignore the biogeochemical and chemical implications of changes to greenhouse gases and aerosols, and do not explore the important ethical, legal, and moral issues that are associated with deliberate geo-engineering efforts. The simulations suggest that the sulfate aerosol produced from the SO2 source in the stratosphere is sufficient to counterbalance most of the warming associated with the greenhouse gas forcing. Surface temperatures return to within a few tenths of a degree(K) of present day levels. Sea ice and precipitation distributions are also much closer to their present day values. The polar region surface temperatures remain 1-3 degrees warm in the winter hemisphere than present day values. This study is very preliminary. Only a subset of the relevant effects have been explored. The effect of such an injection of aerosols on middle atmospheric chemistry, and the effect on cirrus clouds are obvious missing components that merit scrutiny. There are probably others that should be considered. The injection of such aerosols cannot help in ameliorating the effects of CO2 changes on ocean PH, or other effects on the biogeochemistry of the earth system.

  7. Arctic climate response to geoengineering with stratospheric sulfate aerosols

    NASA Astrophysics Data System (ADS)

    McCusker, K. E.; Battisti, D. S.; Bitz, C. M.

    2010-12-01

    Recent warming and record summer sea-ice area minimums have spurred expressions of concern for arctic ecosystems, permafrost, and polar bear populations, among other things. Geoengineering by stratospheric sulfate aerosol injections to deliberately cancel the anthropogenic temperature rise has been put forth as a possible solution to restoring Arctic (and global) climate to modern conditions. However, climate is particularly sensitive in the northern high latitudes, responding easily to radiative forcing changes. To that end, we explore the extent to which tropical injections of stratospheric sulfate aerosol can accomplish regional cancellation in the Arctic. We use the Community Climate System Model version 3 global climate model to execute simulations with combinations of doubled CO2 and imposed stratospheric sulfate burdens to investigate the effects on high latitude climate. We further explore the sensitivity of the polar climate to ocean dynamics by running a suite of simulations with and without ocean dynamics, transiently and to equilibrium respectively. We find that, although annual, global mean temperature cancellation is accomplished, there is over-cooling on land in Arctic summer, but residual warming in Arctic winter, which is largely due to atmospheric circulation changes. Furthermore, the spatial extent of these features and their concurrent impacts on sea-ice properties are modified by the inclusion of ocean dynamical feedbacks.

  8. The Impact of Geoengineering Aerosols on Stratospheric Temperature and Ozone

    NASA Technical Reports Server (NTRS)

    Heckendorn, P.; Weisenstein, D.; Fueglistaler, S.; Luo, B. P.; Rozanov, E.; Schraner, M.; Peter, T.; Thomason, L. W.

    2009-01-01

    Anthropogenic greenhouse gas emissions are warming the global climate at an unprecedented rate. Significant emission reductions will be required soon to avoid a rapid temperature rise. As a potential interim measure to avoid extreme temperature increase, it has been suggested that Earth's albedo be increased by artificially enhancing stratospheric sulfate aerosols. We use a 3D chemistry climate model, fed by aerosol size distributions from a zonal mean aerosol model, to simulate continuous injection of 1-10 Mt/a into the lower tropical stratosphere. In contrast to the case for all previous work, the particles are predicted to grow to larger sizes than are observed after volcanic eruptions. The reason is the continuous supply of sulfuric acid and hence freshly formed small aerosol particles, which enhance the formation of large aerosol particles by coagulation and, to a lesser extent, by condensation. Owing to their large size, these particles have a reduced albedo. Furthermore, their sedimentation results in a non-linear relationship between stratospheric aerosol burden and annual injection, leading to a reduction of the targeted cooling. More importantly, the sedimenting particles heat the tropical cold point tropopause and, hence, the stratospheric entry mixing ratio of H2O increases. Therefore, geoengineering by means of sulfate aerosols is predicted to accelerate the hydroxyl catalyzed ozone destruction cycles and cause a significant depletion of the ozone layer even though future halogen concentrations will be significantly reduced.

  9. The Impact of Geoengineering Aerosols on Stratospheric Temperature and Ozone

    NASA Technical Reports Server (NTRS)

    Heckendorn, P.; Weisenstein, D.; Fueglistaler, S.; Luo, B. P.; Rozanov, E.; Schraner, M.; Thomason, L. W.; Peter, T.

    2011-01-01

    Anthropogenic greenhouse gas emissions are warming the global climate at an unprecedented rate. Significant emission reductions will be required soon to avoid a rapid temperature rise. As a potential interim measure to avoid extreme temperature increase, it has been suggested that Earth's albedo be increased by artificially enhancing stratospheric sulfate aerosols. We use a 3D chemistry climate model, fed by aerosol size distributions from a zonal mean aerosol model. to simulate continuous injection of 1-10 Mt/a into the lower tropical stratosphere. In contrast to the case for all previous work, the particles are predicted to grow to larger sizes than are observed after volcanic eruptions. The reason is the continuous supply of sulfuric acid and hence freshly formed small aerosol particles, which enhance the formation of large aerosol particles by coagulation and, to a lesser extent, by condensation. Owing to their large size, these particles have a reduced albedo. Furthermore, their sedimentation results in a non-linear relationship between stratospheric aerosol burden and annual injection, leading to a reduction of the targeted cooling. More importantly, the sedimenting particles heat the tropical cold point tropopause and, hence, the stratospheric entry mixing ratio of H2O increases. Therefore, geoengineering by means of sulfate aerosols is predicted to accelerate the hydroxyl catalyzed ozone destruction cycles and cause a significant depletion of the ozone layer even though future halogen concentrations will he significantly reduced.

  10. A New Approach to Geoengineering: Manna From Heaven

    NASA Astrophysics Data System (ADS)

    Ellery, Alex

    2015-04-01

    Geo-engineering, although controversial, has become an emerging factor in coping with climate change. Although most are terrestrial-based technologies, I focus on a space-based approach implemented through a solar shield system. I present several new elements that essentially render the high-cost criticism moot. Of special relevance are two seemingly unrelated technologies - the Resource Prospector Mission (RPM) to the Moon in 2018 that shall implement a technology demonstration of simple material resource extraction from lunar regolith, and the emergence of multi-material 3D printing technology that promises unprecedented robotic manufacturing capabilities. My research group has begun theoretical and experimentation work in developing the concept of a 3D printed electric motor system from lunar-type resources. The electric motor underlies every universal mechanical machine. Together with 3D printed electronics, I submit that this would enable self-replicating machines to be realised. A detailed exposition on how this may be achieved will be outlined. Such self-replicating machines could construct the spacecraft required to implement a solar shield and solar power satellites in large numbers from lunar resources with the same underlying technologies at extremely low cost.

  11. Microbially mediated carbon mineralization: Geoengineering a carbon-neutral mine

    NASA Astrophysics Data System (ADS)

    Power, I. M.; McCutcheon, J.; Harrison, A. L.; Wilson, S. A.; Dipple, G. M.; Southam, G.

    2013-12-01

    Ultramafic and mafic mine tailings are a potentially valuable feedstock for carbon mineralization, affording the mining industry an opportunity to completely offset their carbon emissions. Passive carbon mineralization has previously been documented at the abandoned Clinton Creek asbestos mine, and the active Diavik diamond mine and Mount Keith nickel mine, yet the majority of tailings remain unreacted. Examples of microbe-carbonate interactions at each mine suggest that biological pathways could be harnessed to promote carbon mineralization. In suitable environmental conditions, microbes can mediate geochemical processes to accelerate mineral dissolution, increase the supply of carbon dioxide (CO2), and induce carbonate precipitation, all of which may accelerate carbon mineralization. Tailings mineralogy and the availability of a CO2 point source are key considerations in designing tailings storage facilities (TSF) for optimizing carbon mineralization. We evaluate the efficacy of acceleration strategies including bioleaching, biologically induced carbonate precipitation, and heterotrophic oxidation of waste organics, as well as abiotic strategies including enhancing passive carbonation through modifying tailings management practices and use of CO2 point sources (Fig. 1). With the aim of developing carbon-neutral mines, implementation of carbon mineralization strategies into TSF design will be driven by economic incentives and public pressure for environmental sustainability in the mining industry. Figure 1. Schematic illustrating geoengineered scenarios for carbon mineralization of ultramafic mine tailings. Scenarios A and B are based on non-point and point sources of CO2, respectively.

  12. Impacts on Chinese Agriculture of Geoengineering and Smoke from Fires Ignited by Nuclear War

    NASA Astrophysics Data System (ADS)

    Xia, L.; Robock, A.

    2013-12-01

    Climate is one of the most important factors determining crop yields and world food supplies. To be well prepared for possible futures, it is necessary to study yield changes of major crops under different climate scenarios. Here we consider two situations: stratospheric sulfate geoengineering and nuclear war. Although we certainly do not advocate either scenario, we cannot exclude the possibilities: if global warming is getting worse, society might consider deliberately manipulating global temperature; if nuclear weapons still exist, we might face a nuclear war catastrophe. Since in both scenarios there would be reductions of temperature, precipitation, and insolation, which are three controlling factors on crop growth, it is important to study food supply changes under the two cases. We conducted our simulations for China, because it has the highest population and crop production in the world and it is under the strong influence of the summer monsoon, which would be altered in geoengineering and nuclear war scenarios. To examine the effects of climate changes induced by geoengineering and nuclear war on Chinese agriculture, we use the Decision Support System for Agrotechnology Transfer (DSSAT) crop model. We first evaluated the model by forcing it with daily weather data and management practices for the period 1978-2008 for 24 provinces in China, and compared the results to observations of the yields of major crops in China (middle season rice, winter wheat, and maize). Then we perturbed observed weather data using climate anomalies for geoengineering and nuclear war simulations. For geoengineering, we consider the G2 scenario of the Geoengineering Model Intercomparison Project (GeoMIP), which prescribes an insolation reduction to balance a 1% per year increase in CO2 concentration (1pctCO2). We used results from ten climate models participating in G2. For the nuclear war scenario, we consider the effects of 5 Tg of soot that could be injected into the upper

  13. Geoengineering, climate change scepticism and the ‘moral hazard’ argument: an experimental study of UK public perceptions

    PubMed Central

    Corner, Adam; Pidgeon, Nick

    2014-01-01

    Many commentators have expressed concerns that researching and/or developing geoengineering technologies may undermine support for existing climate policies—the so-called moral hazard argument. This argument plays a central role in policy debates about geoengineering. However, there has not yet been a systematic investigation of how members of the public view the moral hazard argument, or whether it impacts on people's beliefs about geoengineering and climate change. In this paper, we describe an online experiment with a representative sample of the UK public, in which participants read one of two arguments (either endorsing or rejecting the idea that geoengineering poses a moral hazard). The argument endorsing the idea of geoengineering as a moral hazard was perceived as more convincing overall. However, people with more sceptical views and those who endorsed ‘self-enhancing’ values were more likely to agree that the prospect of geoengineering would reduce their motivation to make changes in their own behaviour in response to climate change. The findings suggest that geoengineering is likely to pose a moral hazard for some people more than others, and the implications for engaging the public are discussed. PMID:25404680

  14. 32nd Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Walker, S. W. (Compiler); Boesiger, Edward A. (Compiler)

    1998-01-01

    The proceedings of the 32nd Aerospace Mechanism Symposium are reported. NASA John F. Kennedy Space Center (KSC) hosted the symposium that was held at the Hilton Oceanfront Hotel in Cocoa Beach, Florida on May 13-15, 1998. The symposium was cosponsored by Lockheed Martin Missiles and Space and the Aerospace Mechanisms Symposium Committee. During these days, 28 papers were presented. Topics included robotics, deployment mechanisms, bearing, actuators, scanners, boom and antenna release, and test equipment.

  15. YouTube Fridays: Student Led Development of Engineering Estimate Problems

    ERIC Educational Resources Information Center

    Liberatore, Matthew W.; Vestal, Charles R.; Herring, Andrew M.

    2012-01-01

    YouTube Fridays devotes a small fraction of class time to student-selected videos related to the course topic, e.g., thermodynamics. The students then write and solve a homework-like problem based on the events in the video. Three recent pilots involving over 300 students have developed a database of videos and questions that reinforce important…

  16. Education in Northern Ireland since the Good Friday Agreement: Kabuki Theatre Meets "Danse Macabre"

    ERIC Educational Resources Information Center

    Gardner, John

    2016-01-01

    The Good Friday Agreement (1998) between the UK and Irish governments, and most of the political parties in Northern Ireland, heralded a significant step forward in securing peace and stability for this troubled region of the British Isles. From the new-found stability, the previous fits and starts of education reform were replaced by a…

  17. Friday Forum and the AICPA Core Competency Framework: Honing Students' Personal Competencies

    ERIC Educational Resources Information Center

    Johnson, Grace F.

    2013-01-01

    This paper shares one learning technique for honing undergraduate students' personal competencies. The senior accounting capstone course at a small Midwestern private liberal college includes a weekly seminar series, called the Friday Forum, where students and practitioners meet to discuss a current professional accounting article. Since Spring…

  18. GEO-ENGINEERING MODELING THROUGH INTERNET INFORMATICS (GEMINI)

    SciTech Connect

    W. Lynn Watney; John H. Doveton

    2004-05-13

    GEMINI (Geo-Engineering Modeling through Internet Informatics) is a public-domain web application focused on analysis and modeling of petroleum reservoirs and plays (http://www.kgs.ukans.edu/Gemini/index.html). GEMINI creates a virtual project by ''on-the-fly'' assembly and analysis of on-line data either from the Kansas Geological Survey or uploaded from the user. GEMINI's suite of geological and engineering web applications for reservoir analysis include: (1) petrofacies-based core and log modeling using an interactive relational rock catalog and log analysis modules; (2) a well profile module; (3) interactive cross sections to display ''marked'' wireline logs; (4) deterministic gridding and mapping of petrophysical data; (5) calculation and mapping of layer volumetrics; (6) material balance calculations; (7) PVT calculator; (8) DST analyst, (9) automated hydrocarbon association navigator (KHAN) for database mining, and (10) tutorial and help functions. The Kansas Hydrocarbon Association Navigator (KHAN) utilizes petrophysical databases to estimate hydrocarbon pay or other constituent at a play- or field-scale. Databases analyzed and displayed include digital logs, core analysis and photos, DST, and production data. GEMINI accommodates distant collaborations using secure password protection and authorized access. Assembled data, analyses, charts, and maps can readily be moved to other applications. GEMINI's target audience includes small independents and consultants seeking to find, quantitatively characterize, and develop subtle and bypassed pays by leveraging the growing base of digital data resources. Participating companies involved in the testing and evaluation of GEMINI included Anadarko, BP, Conoco-Phillips, Lario, Mull, Murfin, and Pioneer Resources.

  19. Impact of Geoengineering Schemes on the Global Hydrological Cycle

    SciTech Connect

    Bala, G; Duffy, P; Taylor, K

    2007-12-07

    The rapidly rising CO{sub 2} level in the atmosphere has led to proposals of climate stabilization via 'Geoengineering' schemes that would mitigate climate change by intentionally reducing the solar radiation incident on earth's surface. In this paper, we address the impact of these climate stabilization schemes on the global hydrological cycle, using equilibrium simulations from an atmospheric general circulation model coupled to a slab ocean model. We show that insolation reductions sufficient to offset global-scale temperature increases lead to a decrease in the intensity of the global hydrologic cycle. This occurs because solar forcing is more effective in driving changes in global mean evaporation than is CO{sub 2} forcing of a similar magnitude. In the model used here, the hydrologic sensitivity, defined as the percentage change in global mean precipitation per degree warming, is 2.4% for solar forcing, but only 1.5% for CO{sub 2} forcing. Although other models and the climate system itself may differ quantitatively from this result, the conclusion can be understood based on simple considerations of the surface energy budget and thus is likely to be robust. Compared to changing temperature by altering greenhouse gas concentrations, changing temperature by varying insolation results in larger changes in net radiative fluxes at the surface; these are compensated by larger changes in latent and sensible heat fluxes. Hence the hydrological cycle is more sensitive to temperature adjustment via changes in insolation than changes in greenhouse gases. This implies that an alteration in solar forcing might offset temperature changes or hydrological changes from greenhouse warming, but could not cancel both at once.

  20. Impact of geoengineering schemes on the global hydrological cycle.

    PubMed

    Bala, G; Duffy, P B; Taylor, K E

    2008-06-01

    The rapidly rising CO(2) level in the atmosphere has led to proposals of climate stabilization by "geoengineering" schemes that would mitigate climate change by intentionally reducing solar radiation incident on Earth's surface. In this article we address the impact of these climate stabilization schemes on the global hydrological cycle. By using equilibrium climate simulations, we show that insolation reductions sufficient to offset global-scale temperature increases lead to a decrease in global mean precipitation. This occurs because solar forcing is more effective in driving changes in global mean evaporation than is CO(2) forcing of a similar magnitude. In the model used here, the hydrological sensitivity, defined as the percentage change in global mean precipitation per degree warming, is 2.4% K(-1) for solar forcing, but only 1.5% K(-1) for CO(2) forcing. Although other models and the climate system itself may differ quantitatively from this result, the conclusion can be understood based on simple considerations of the surface energy budget and thus is likely to be robust. For the same surface temperature change, insolation changes result in relatively larger changes in net radiative fluxes at the surface; these are compensated by larger changes in the sum of latent and sensible heat fluxes. Hence, the hydrological cycle is more sensitive to temperature adjustment by changes in insolation than by changes in greenhouse gases. This implies that an alteration in solar forcing might offset temperature changes or hydrological changes from greenhouse warming, but could not cancel both at once. PMID:18505844

  1. A new Geoengineering Model Intercomparison Project (GeoMIP) experiment designed for climate and chemistry models

    DOE PAGESBeta

    Tilmes, S.; Mills, Mike; Niemeier, Ulrike; Schmidt, Hauke; Robock, Alan; Kravitz, Benjamin S.; Lamarque, J. F.; Pitari, G.; English, J. M.

    2015-01-15

    A new Geoengineering Model Intercomparison Project (GeoMIP) experiment "G4 specified stratospheric aerosols" (short name: G4SSA) is proposed to investigate the impact of stratospheric aerosol geoengineering on atmosphere, chemistry, dynamics, climate, and the environment. In contrast to the earlier G4 GeoMIP experiment, which requires an emission of sulfur dioxide (SO₂) into the model, a prescribed aerosol forcing file is provided to the community, to be consistently applied to future model experiments between 2020 and 2100. This stratospheric aerosol distribution, with a total burden of about 2 Tg S has been derived using the ECHAM5-HAM microphysical model, based on a continuous annualmore » tropical emission of 8 Tg SO₂ yr⁻¹. A ramp-up of geoengineering in 2020 and a ramp-down in 2070 over a period of 2 years are included in the distribution, while a background aerosol burden should be used for the last 3 decades of the experiment. The performance of this experiment using climate and chemistry models in a multi-model comparison framework will allow us to better understand the impact of geoengineering and its abrupt termination after 50 years in a changing environment. The zonal and monthly mean stratospheric aerosol input data set is available at https://www2.acd.ucar.edu/gcm/geomip-g4-specified-stratospheric-aerosol-data-set.« less

  2. A new Geoengineering Model Intercomparison Project (GeoMIP) experiment designed for climate and chemistry models

    NASA Astrophysics Data System (ADS)

    Tilmes, S.; Mills, M. J.; Niemeier, U.; Schmidt, H.; Robock, A.; Kravitz, B.; Lamarque, J.-F.; Pitari, G.; English, J. M.

    2015-01-01

    A new Geoengineering Model Intercomparison Project (GeoMIP) experiment "G4 specified stratospheric aerosols" (short name: G4SSA) is proposed to investigate the impact of stratospheric aerosol geoengineering on atmosphere, chemistry, dynamics, climate, and the environment. In contrast to the earlier G4 GeoMIP experiment, which requires an emission of sulfur dioxide (SO2) into the model, a prescribed aerosol forcing file is provided to the community, to be consistently applied to future model experiments between 2020 and 2100. This stratospheric aerosol distribution, with a total burden of about 2 Tg S has been derived using the ECHAM5-HAM microphysical model, based on a continuous annual tropical emission of 8 Tg SO2 yr-1. A ramp-up of geoengineering in 2020 and a ramp-down in 2070 over a period of 2 years are included in the distribution, while a background aerosol burden should be used for the last 3 decades of the experiment. The performance of this experiment using climate and chemistry models in a multi-model comparison framework will allow us to better understand the impact of geoengineering and its abrupt termination after 50 years in a changing environment. The zonal and monthly mean stratospheric aerosol input data set is available at https://www2.acd.ucar.edu/gcm/geomip-g4-specified-stratospheric-aerosol-data-set.

  3. Crop failure rates in a geoengineered climate: impact of climate change and marine cloud brightening

    NASA Astrophysics Data System (ADS)

    Parkes, B.; Challinor, A.; Nicklin, K.

    2015-08-01

    The impact of geoengineering on crops has to date been studied by examining mean yields. We present the first work focusing on the rate of crop failures under a geoengineered climate. We investigate the impact of a future climate and a potential geoengineering scheme on the number of crop failures in two regions, Northeastern China and West Africa. Climate change associated with a doubling of atmospheric carbon dioxide increases the number of crop failures in Northeastern China while reducing the number of crop failures in West Africa. In both regions marine cloud brightening is likely to reduce the number crop failures, although it is more effective at reducing mild crop failure than severe crop failure. We find that water stress, rather than heat stress, is the main cause of crop failure in current, future and geoengineered climates. This demonstrates the importance of irrigation and breeding for tolerance to water stress as adaptation methods in all futures. Analysis of global rainfall under marine cloud brightening has the potential to significantly reduce the impact of climate change on global wheat and groundnut production.

  4. A new Geoengineering Model Intercomparison Project (GeoMIP) experiment designed for climate and chemistry models

    SciTech Connect

    Tilmes, S.; Mills, Mike; Niemeier, Ulrike; Schmidt, Hauke; Robock, Alan; Kravitz, Benjamin S.; Lamarque, J. F.; Pitari, G.; English, J. M.

    2015-01-15

    A new Geoengineering Model Intercomparison Project (GeoMIP) experiment "G4 specified stratospheric aerosols" (short name: G4SSA) is proposed to investigate the impact of stratospheric aerosol geoengineering on atmosphere, chemistry, dynamics, climate, and the environment. In contrast to the earlier G4 GeoMIP experiment, which requires an emission of sulfur dioxide (SO₂) into the model, a prescribed aerosol forcing file is provided to the community, to be consistently applied to future model experiments between 2020 and 2100. This stratospheric aerosol distribution, with a total burden of about 2 Tg S has been derived using the ECHAM5-HAM microphysical model, based on a continuous annual tropical emission of 8 Tg SO₂ yr⁻¹. A ramp-up of geoengineering in 2020 and a ramp-down in 2070 over a period of 2 years are included in the distribution, while a background aerosol burden should be used for the last 3 decades of the experiment. The performance of this experiment using climate and chemistry models in a multi-model comparison framework will allow us to better understand the impact of geoengineering and its abrupt termination after 50 years in a changing environment. The zonal and monthly mean stratospheric aerosol input data set is available at https://www2.acd.ucar.edu/gcm/geomip-g4-specified-stratospheric-aerosol-data-set.

  5. Impact Of Geo-engineered Aerosols On Stratospheric Chemistry And Dynamics

    NASA Astrophysics Data System (ADS)

    Tilmes, S.; Garcia, R. R.; Kinnison, D. E.; Gettelman, A.; Rasch, P. J.

    2008-12-01

    Geo-engineering schemes have been proposed to alleviate the consequences of global warming; one proposed scheme is to inject sulfur into the stratosphere so as to mimic the effects of large volcanic eruptions. Past volcanic eruptions have shown that strongly enhanced sulfate aerosols in the stratosphere result in a higher planetary albedo, leading to surface cooling. However, the increase of sulfate aerosol surface area enhances heterogeneous reactions in the stratosphere that lead to ozone loss. The potential for high Arctic ozone depletion in the context of geo-engineering is known. On the other hand, halogen compounds are now decreasing in the atmosphere as a result of the enforcement of the Montreal Protocol and its amendments, and this is expected to bring about the recovery of the ozone layer and to lessen the potential impact of aerosols. In this study we present results of calculations made with NCAR's Whole Atmosphere Community Climate Model (WACCM), focusing on the impact of Geo-engineering on stratospheric chemistry and dynamics. Aside from changes in heterogeneous reactions, changes in stratospheric dynamics have a significant impact on ozone. On average, changes of both chemistry and dynamics result in a slowdown of the recovery of ozone for mid- and high latitudes. An increase of ozone depletion as a result of geo-engineering was found in both polar regions for the period between 2040-2050.

  6. Screening Level Analysis of Several Geo-engineering Techniques Intended to Mitigate Global Warming

    NASA Astrophysics Data System (ADS)

    Mills, W. B.

    2007-12-01

    Within the past few years, a number of papers have appeared in the literature that describe alternative geo- engineering techniques that could be used to supplement more mainstream options to mitigate global warming. An example of a mainstream option is carbon capture and storage, and an example of a geo-engineering approach is an orbiting satellite that provides a sun-shade to earth. These supplemental geo-engineering techniques, which are controversial for reasons such as they appear to allow emissions of carbon to continue unabated, are really intended to bridge the time gap between where we are today and where we need to be in terms of the implementation of mainstream mitigation schemes. Allowing that geo-engineering techniques are controversial, and could cause more harm than good, there are still reasons to examine them. As an example, would it be possible to "uncommitt" from projected sea level rise that already threatens low-lying countries by reducing incoming solar radiation? For this poster, then, several alternative geo-engineering techniques (which can broadly be classified as space-based and earth-based) will be examined. A screening level global equilibrium radiation model will be used to examine the global temperature response to various alternatives, implemented at scales proposed by their developers. The equilibrium model will provide an estimate of global temperature change once the perturbed energy fluxes have returned to a balanced state. Thus the time frame of radiation adjustment will not be evaluated. Further, since we know that greenhouse gas emissions will likely continue to increase for decades into the future, the efficacy of any geo-engineering scheme could diminish over time unless appropriate modifications to the operation of those schemes are made. This aspect of time evolution of geo-engineering will also be discussed. Finally, since there does not appear to be a "silver bullet" solution to climate change, either from mainstream

  7. The VLT Opening Symposium

    NASA Astrophysics Data System (ADS)

    Bergeron, J.

    1999-06-01

    The beginning of the VLT era was marked by two major events: the VLT Official Inauguration Ceremony at Paranal on 5 March 1999, preceded by the VLT Opening Symposium on 1-4 March. ESO is indebted to Professor J.A. Music Tomicic, Rector of the Universidad Católica del Norte, for hosting this symposium. Another major event occurred on the night of 4 March: First light was achieved ahead of schedule at Kueyen, the second 8.2-m VLT unit telescope.

  8. 2001 Flight Mechanics Symposium

    NASA Technical Reports Server (NTRS)

    Lynch, John P. (Editor)

    2001-01-01

    This conference publication includes papers and abstracts presented at the Flight Mechanics Symposium held on June 19-21, 2001. Sponsored by the Guidance, Navigation and Control Center of Goddard Space Flight Center, this symposium featured technical papers on a wide range of issues related to attitude/orbit determination, prediction and control; attitude simulation; attitude sensor calibration; theoretical foundation of attitude computation; dynamics model improvements; autonomous navigation; constellation design and formation flying; estimation theory and computational techniques; Earth environment mission analysis and design; and, spacecraft re-entry mission design and operations.

  9. The fate of the Greenland Ice Sheet in a geoengineered, high CO2 world

    NASA Astrophysics Data System (ADS)

    Irvine, Peter J.; Lunt, Daniel J.; Stone, Emma J.; Ridgwell, Andy

    2009-10-01

    Solar radiation management (SRM) geoengineering has been proposed as one means of helping avoid the occurrence of dangerous climate change and undesirable state transitions ('tipping points') in the Earth system. The irreversible melting of the Greenland Ice Sheet is a case in point—a state transition that could occur as a result of CO2-driven elevated global temperatures, and one leading to potentially catastrophic sea-level rise. SRM schemes such as the creation of a 'sunshade' or injection of sulfate aerosols into the stratosphere could reduce incoming solar radiation, and in theory balance, in a global mean, the greenhouse warming resulting from elevated concentrations of CO2 in the atmosphere. Previous work has highlighted that a geoengineered world would have: warming towards the poles, cooling in the tropics, and a reduction in the global hydrological cycle, which may have important implications for the Greenland Ice Sheet. Using a fully coupled global climate model in conjunction with an ice sheet model, we assess the consequences for the mass balance of the Greenland Ice Sheet of the reorganization of climate patterns by the combination of high CO2 and geoengineering. We find that Greenland surface temperature and precipitation anomalies, compared to the pre-industrial situation, decrease almost linearly with increasing levels of SRM geoengineering, but that these combine to create a highly non-linear response of the ice sheet. The substantial melting of the Greenland Ice Sheet predicted for four times pre-industrial CO2 levels is prevented in our model with only a partial application of SRM, and hence without having to fully restore the global average temperature back to pre-industrial levels. This suggests that the degree of SRM geoengineering required to mitigate the worst impacts of greenhouse warming, such as sea-level rise, need not be as extensive as generally assumed.

  10. SPICE Work Package 3: Modelling the Effects of Stratospheric Aerosol Geoengineering

    NASA Astrophysics Data System (ADS)

    Driscoll, Simon

    2015-04-01

    This talk presents the results of the SPICE Work Package 3. There is an obvious need for methods to verify the accuracy of geoengineering given no observations of a geoengineering programme. Accordingly, model ability in reproducing the observed dynamical response to volcanic eruptions is discussed using analysis of CMIP5 data and different configurations of the HadGEM2 model. With the HadGEM2-L60 model shown to be substantially better in reproducing the observed dynamical response to volcanic eruptions, simulations of GeoMIP's G4 scenario are performed. Simulated impacts of geoengineering are described, and asymmetries between the immediate onset and immediate cessation ('termination') of geoengineering are analysed. Whilst a rapid large increase in stratospheric sulphate aerosols (such as from volcanic eruptions) can cause substantial damage, most volcanic eruptions in general are not catastrophic. One may therefore suspect that an 'equal but opposite' change in radiative forcing from termination may therefore not be catastrophic, if the climatic response is simulated to be symmetric. HadGEM2 simulations reveal a substantially more rapid change in variables such as near-surface temperature and precipitation following termination than the onset, indicating that termination may be substantially more damaging and even catastrophic. Some suggestions for hemispherically asymmetric geoengineering have been proposed as a way to reduce Northern Hemisphere sea ice, for example, with lesser impacts on the rest of the climate. However, HadGEM2 simulations are performed and observations analysed following volcanic eruptions. Both indicate substantial averse consequences from hemispherically asymmetric loading of stratospheric loading on precipitation in the Sahelian region - a vulnerable region where drought has caused hundreds of thousands of deaths and created millions of refugees in the past.

  11. Direct and indirect effects of sea spray geoengineering and the role of injected particle size

    NASA Astrophysics Data System (ADS)

    Partanen, Antti-Ilari; Kokkola, Harri; Romakkaniemi, Sami; Kerminen, Veli-Matti; Lehtinen, Kari E. J.; Bergman, Tommi; Arola, Antti; Korhonen, Hannele

    2012-01-01

    Climate-aerosol model ECHAM5.5-HAM2 was used to investigate how geoengineering with artificial sea salt emissions would affect marine clouds and the Earth's radiative balance. Prognostic cloud droplet number concentration and interaction of aerosol particles with clouds and radiation were calculated explicitly, thus making this the first time that aerosol direct effects of sea spray geoengineering are considered. When a wind speed dependent baseline geoengineering flux was applied over all oceans (total annual emissions 443.9 Tg), we predicted a radiative flux perturbation (RFP) of -5.1 W m-2, which is enough to counteract warming from doubled CO2 concentration. When the baseline flux was limited to three persistent stratocumulus regions (3.3% of Earth's surface, total annual emissions 20.6 Tg), the RFP was -0.8 Wm-2 resulting mainly from a 74-80% increase in cloud droplet number concentration and a 2.5-4.4 percentage point increase in cloud cover. Multiplying the baseline mass flux by 5 or reducing the injected particle size from 250 to 100 nm had comparable effects on the geoengineering efficiency with RFPs -2.2 and -2.1 Wm-2, respectively. Within regions characterized with persistent stratocumulus decks, practically all of the radiative effect originated from aerosol indirect effects. However, when all oceanic regions were seeded, the direct effect with the baseline flux was globally about 29% of the total radiative effect. Together with previous studies, our results indicate that there are still large uncertainties associated with the sea spray geoengineering efficiency due to variations in e.g., background aerosol concentration, updraft velocity, cloud altitude and onset of precipitation.

  12. Technical Entrepreneurship: A Symposium.

    ERIC Educational Resources Information Center

    Cooper, Arnold C., Ed.; Komives, John L., Ed.

    Contained in this document are papers presented at the Symposium on Technical Entrepreneurship at Purdue University by researchers who were then or had previously been engaged in research in the area. Because formal research in this area was in its infancy, there was a particular need to afford investigators in the field opportunities to compare…

  13. Standards and Certification. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on standards and certification in human resource development (HRD). "Implementing Management Standards in the UK" (Jonathan Winterton, Ruth Winterton) reports on a study that explored the implementation of management standards in 16 organizations and identified 36 key themes and strategic issues…

  14. Globalism and HRD. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on globalization and human resource development (HRD). "Challenges and Strategies of Developing Human Resources in the Surge of Globalization: A Case of the People's Republic of China" (De Zhang, Baiyin Yang, Yichi Zhang) analyzes the challenges and strategies of HRD in China and discusses the…

  15. Online Learning. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on online learning that was conducted as part of a conference on human resource development (HRD). "An Instructional Strategy Framework for Online Learning Environments" (Scott D. Johnson, Steven R. Aragon) discusses the pitfalls of modeling online courses after traditional instruction instead…

  16. Fifth Cooley's anemia symposium

    SciTech Connect

    Bank, A.; Anderson, W.F.; Zaino, E.C.

    1985-01-01

    This book discusses the topics presented at the symposium on the subject of 'Thalassemia'. Sickle cell anemia is also briefly discussed. The aspects discussed are chromosomal defects of anemias particularly globin synthesis, and the role of messenger RNA and other chromosomes.

  17. ASSA Symposium 2012 Abstracts

    NASA Astrophysics Data System (ADS)

    2012-10-01

    of papers presented at the ASSA Symposium held in Cape Town 12-14 October 2012. Videos are available on You tube. See http://www.youtube.com/playlist?list=PL8odLrzpzMkHS-cSEfPFIr3YLPAq4d5MU for a playlist.

  18. Research Symposium I

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The proceedings of this symposium consist of abstracts of talks presented by interns at NASA Glenn Research Center (GRC). The interns assisted researchers at GRC in projects which primarily address the following topics: aircraft engines and propulsion, spacecraft propulsion, fuel cells, thin film photovoltaic cells, aerospace materials, computational fluid dynamics, aircraft icing, management, and computerized simulation.

  19. Tools in HRD. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on tools in human resource development (HRD). "Game Theory Methodology in HRD" (Thomas J. Chermack, Richard A. Swanson) explores the utility of game theory in helping the HRD profession address the complexity of integrating multiple theories for disciplinary understanding and fulfilling its…

  20. Recruitment and Training. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on recruitment and training. "College Choice: The State of Marketing and Effective Student Recruitment Strategies" (Fredrick Muyia Nafukho, Michael F. Burnett) reports on a study of the recruitment strategies used by Louisiana State University's admissions office and College of Agriculture that…

  1. European Cosmic Ray Symposium

    ScienceCinema

    None

    2011-04-25

    13me Symposium qui se déroule du 27 au 31 juillet pour la première fois au Cern. Brian Pattison ouvre la cérémonie et donne la parole à Dr.Ugland (qui représente le DG C.Rubbia excusé) et d'autres intervenants

  2. Competencies in HRD. Symposium.

    ERIC Educational Resources Information Center

    2002

    This symposium is comprised of three papers on competencies in human resource development (HRD). "The Development of a Competency Model and Assessment Instrument for Public Sector Leadership and Management Development" (Sharon S. Naquin, Elwood F. Holton III) reports on a streamlined methodology and process used to develop a competency model for…

  3. Quality of Life Symposium.

    ERIC Educational Resources Information Center

    New Mexico State Univ., Las Cruces. New Mexico Environmental Inst.

    Comments, speeches, and questions delivered at the Quality of Life Symposium are compiled in these proceedings. As an exploratory session, the conference objectives were to (1) become better informed about New Mexico--its resource base, the economy, social and cultural base, and the environment; and (2) to evaluate and discuss the role of New…

  4. Values: A Symposium Report.

    ERIC Educational Resources Information Center

    Ryan, T. A., Ed.

    This publication brings together a set of four papers prepared for a symposium on values at the 1972 annual meeting of the American Educational Research Association. The first paper, by Fred N. Kerlinger, establishes a rationale for values research. The discussion focuses on the definition of values, relationship between values and attitudes,…

  5. Issues of HRD. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on issues of human resource development (HRD). "The Complex Roots of Human Resource Development" (Monica Lee) discusses the roots of HRD within the framework of the following views of management: (1) classic (the view that managers must be able to create appropriate rules and procedures for…

  6. Team Based Work. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on team-based work in human resource development (HRD). "Toward Transformational Learning in Organizations: Effects of Model-II Governing Variables on Perceived Learning in Teams" (Blair K. Carruth) summarizes a study that indicated that, regardless of which Model-II variable (valid information,…

  7. Issues of Gender. Symposium.

    ERIC Educational Resources Information Center

    2002

    This symposium is comprised of three papers on issues of gender in human resource development (HRD). "The Impact of Awareness and Action on the Implementation of a Women's Network" (Laura L. Bierema) reports on research to examine how gender consciousness emerges through the formation of in-company networks to promote corporate women's status. It…

  8. Alteration and fluid flow around a sulfide-carbonate-quartz vein, Lucky Friday mine, Northern Idaho

    SciTech Connect

    Gitlin, E.C.

    1985-01-01

    Wall rocks at the Lucky Friday mine, Coeur d'Alene district, Idaho, contain a >500m wide zone about a steeply dipping Pb-Zn-Ag vein. This zone has experienced local conditions distinct from the regional metamorphism of the quartzite + argillite host rock. Within the district, the host rock (Precambrian Revett Formation) has undergone low grade metamorphism and contains varying proportions of quartz, phengitic muscovite, detrital alkali feldspar, magnetite, hematite, ilmenite, rutile, zircon, tourmaline, +/- calcite, +/- ankeritic dolomite. In contrast, the Lucky Friday wall rocks lack feldspar and Fe-bearing oxides, and contain Fe-poor muscovite and up to 40% carbonate: siderite, ankerite, and/or calcite. A comparison of district-wide Revett rocks with Lucky Friday wall rocks suggests that the wall rocks have undergone localized dephengitization with concomitant Fe-enrichment in the carbonates and Fe-depletion of the oxides. Pertinent metamorphic reactions consume CO/sub 2/ and liberate H/sub 2/O. Fluid inclusions from the vein and wall rock stringers have homogenization temperatures from approx. =200/sup 0/ to <375/sup 0/C, but they define no temperature gradient. With few exceptions, compositions of the carbonates are identical throughout the altered wall rock. These observations suggest that the carbonate subzone contacts are not isograds but isofluxes: the loci of equivalent fluid/reactant mineral ratio. The disposition of isofluxes around a dominant fluid channelway, i.e. the vein, affords an opportunity to interpret fluid flow pathways during low temperatures metamorphism.

  9. A multi-model assessment of the impact of sea spray geoengineering on cloud droplet number

    NASA Astrophysics Data System (ADS)

    Pringle, K. J.; Carslaw, K. S.; Fan, T.; Mann, G. W.; Hill, A.; Stier, P.; Zhang, K.; Tost, H.

    2012-12-01

    Artificially increasing the albedo of marine boundary layer clouds by the mechanical emission of sea spray aerosol has been proposed as a geoengineering technique to slow the warming caused by anthropogenic greenhouse gases. A previous global model study (Korhonen et al., 2010) found that only modest increases (< 20%) and sometimes even decreases in cloud drop number (CDN) concentrations would result from emission scenarios calculated using a windspeed dependent geoengineering flux parameterisation. Here we extend that work to examine the conditions under which decreases in CDN can occur, and use three independent global models to quantify maximum achievable CDN changes. We find that decreases in CDN can occur when at least three of the following conditions are met: the injected particle number is < 100 cm-3, the injected diameter is > 250-300 nm, the background aerosol loading is large (≥ 150 cm-3) and the in-cloud updraught velocity is low (< 0.2 m s-1). With lower background loadings and/or increased updraught velocity, significant increases in CDN can be achieved. None of the global models predict a decrease in CDN as a result of geoengineering, although there is considerable diversity in the calculated efficiency of geoengineering, which arises from the diversity in the simulated marine aerosol distributions. All three models show a small dependence of geoengineering efficiency on the injected particle size and the geometric standard deviation of the injected mode. However, the achievability of significant cloud drop enhancements is strongly dependent on the cloud updraught speed. With an updraught speed of 0.1 m s-1 a global mean CDN of 375 cm-3 (previously estimated to cancel the forcing caused by CO2 doubling) is achievable in only about 50% of grid boxes which have > 50% cloud cover, irrespective of the amount of aerosol injected. But at stronger updraft speeds (0.2 m s-1), higher values of CDN are achievable due to the elevated in-cloud supersaturations

  10. Second International Lygus Symposium

    PubMed Central

    Goodell, P. B.; Ellsworth, Peter C.

    2008-01-01

    The Second International Lygus Symposium brought together 52 entomologists from six nations and 11 states representing universities, public agencies, and private entities to discuss the latest research on Lygus species and their relatives. Symposium topics included Lygus biology, behavior and ecology, IPM, insecticides and resistance, and biological control. Papers and posters dealt with Lygus as a pest of several crops, including cotton, strawberries, seed alfalfa, canola, dry beans, cucumbers, cereals, peaches, and new crops guayule and lesquerella. Intercrop movement of Lygus2008200820082008 species was another important topic of many presentations. In the capstone session, participants identified needs and priorities for ongoing Lygus research and education (available at http://ag.arizona.edu/apmc/Arid_SWPMC_RAMP.html). The conference was sponsored in part by FMC Corporation, the University of Arizona Arizona Pest Management Center, the University of California Statewide IPM Program, and a grant to Ellsworth et al. (CRIS# 0207436) from the USDA-CSREES, Risk Avoidance and Mitigation Program (RAMP).

  11. Microgravity Fluid Management Symposium

    NASA Technical Reports Server (NTRS)

    1987-01-01

    The NASA Microgravity Fluid Management Symposium, held at the NASA Lewis Research Center, September 9 to 10, 1986, focused on future research in the microgravity fluid management field. The symposium allowed researchers and managers to review space applications that require fluid management technology, to present the current status of technology development, and to identify the technology developments required for future missions. The 19 papers covered three major categories: (1) fluid storage, acquisition, and transfer; (2) fluid management applications, i.e., space power and thermal management systems, and environmental control and life support systems; (3) project activities and insights including two descriptions of previous flight experiments and a summary of typical activities required during development of a shuttle flight experiment.

  12. 1979 DOE statistical symposium

    SciTech Connect

    Gardiner, D.A.; Truett T.

    1980-09-01

    The 1979 DOE Statistical Symposium was the fifth in the series of annual symposia designed to bring together statisticians and other interested parties who are actively engaged in helping to solve the nation's energy problems. The program included presentations of technical papers centered around exploration and disposal of nuclear fuel, general energy-related topics, and health-related issues, and workshops on model evaluation, risk analysis, analysis of large data sets, and resource estimation.

  13. Space 2000 Symposium

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The purpose of the Space 2000 Symposium is to present the creativity and achievements of key figures of the 20th century. It offers a retrospective discussion on space exploration. It considers the future of the enterprise, and the legacy that will be left for future generations. The symposium includes panel discussions, smaller session meetings with some panelists, exhibits, and displays. The first session entitled "From Science Fiction to Science Facts" commences after a brief overview of the symposium. The panel discussions include talks on space exploration over many decades, and the missions of the millennium to search for life on Mars. The second session, "Risks and Rewards of Human Space Exploration," focuses on the training and health risks that astronauts face on their exploratory mission to space. Session three, "Messages and Messengers Informing and Inspire Space Exploration and the Public," focuses on the use of TV medium by educators and actors to inform and inspire a wide variety of audiences with adventures of space exploration. Session four, "The Legacy of Carl Sagan," discusses the influences made by Sagan to scientific research and the general public. In session five, "Space Exploration for a new Generation," two student speakers and the NASA Administrator Daniel S. Goldin address the group. Session six, "Destiny or Delusion? -- Humankind's Place in the Cosmos," ends the symposium with issues of space exploration and some thought provoking questions. Some of these issues and questions are: what will be the societal implications if we discover the origin of the universe, stars, or life; what will be the impact if scientists find clear evidence of life outside the domains of the Earth; should there be limits to what humans can or should learn; and what visionary steps should space-faring people take now for future generations.

  14. Eighth particulate control symposium

    SciTech Connect

    Not Available

    1990-11-01

    The Eighth Symposium on the Transfer and Utilization of Particulate Control Technology was held in San Diego, California, March 20 through 23, 1990. The symposium proceedings contain 80 papers presented by representatives of utility companies, equipment and process suppliers, university representatives, research and development companies, EPA and other federal and state agency representatives, and EPRI staff members. Electrostatic precipitators and fabric filters were the major topics discussed during the symposium. Papers from this conference are organized by session in two volumes. This Volume (2) contains papers presented in the sessions on: low ratio baghouse O M experience, pulse-jet baghouse experience, particulate control for AFBCs, particulate control for dry SO2 control processes, baghouse design and performance, fundamental baghouse studies, high temperature filtration, and control of emissions from RDF incinerators. Both fabric filters and ESPs are discussed in the AFBC and dry SO2 control papers. The high temperature filtration papers deal with ceramic barrier and granular bed filters. The rest of the papers in Volume 2 are concerned with fabric filters on pulverized-coal-fired boilers. Individual projects are processed separately for the data bases.

  15. LHC Nobel Symposium Proceedings

    NASA Astrophysics Data System (ADS)

    Ekelöf, Tord

    2013-12-01

    In the summer of 2012, a great discovery emerged at the Large Hadron Collider (LHC) at CERN in Geneva. A plethora of new precision data had already by then been collected by the ATLAS and CMS experiments at LHC, providing further extensive support for the validity of the Standard Model of particle physics. But what now appeared was the first evidence for what was not only the last unverified prediction of the Standard Model, but also perhaps the most decisive one: the prediction made already in 1964 of a unique scalar boson required by the theory of François Englert and Peter Higgs on how fundamental particles acquire mass. At that moment in 2012, it seemed particularly appropriate to start planning a gathering of world experts in particle physics to take stock of the situation and try to answer the challenging question: what next? By May 2013, when the LHC Nobel Symposium was held at the Krusenberg Mansion outside Uppsala in Sweden, the first signs of a great discovery had already turned into fully convincing experimental evidence for the existence of a scalar boson of mass about 125 GeV, having properties compatible with the 50-year-old prediction. And in October 2013, the evidence was deemed so convincing that the Swedish Royal Academy of Sciences awarded the Nobel Prize in Physics to Englert and Higgs for their pioneering work. At the same time the search at the LHC for other particles, beyond those predicted by the Standard Model, with heavier masses up to—and in some cases beyond—1 TeV, had provided no positive result. The triumph of the Standard Model seems resounding, in particular because the mass of the discovered scalar boson is such that, when identified with the Higgs boson, the Standard Model is able to provide predictions at energies as high as the Planck mass, although at the price of accepting that the vacuum would be metastable. However, even if there were some feelings of triumph, the ambience at the LHC Nobel Symposium was more one of

  16. ECOSYSTEM IMPACTS OF GEOENGINEERING: A Review for Developing a Science Plan

    SciTech Connect

    Russell, Lynn M.; Rasch, Philip J.; Mace, Georgina; Jackson, Robert B.; Shepherd, John; Liss, Peter; Leinen, Margaret; Schimel, David; Vaughan, Naomi E.; Janetos, Anthony C.; Boyd, Philip W.; Norby, Richard J.; Caldeira, Ken; Merikanto, Joonas; Artaxo, Paulo; Melillo, Jerry; Morgan, M. Granger

    2012-06-01

    Geoengineering methods are intended to reduce the magnitude of climate change. Climate change in some regions is already having demonstrable effects on ecosystem structure and functioning. Two different types of geoengineering activities have been proposed: carbon dioxide removal (CDR), which includes a range of engineered and biological processes to remove carbon dioxide (CO2) from the atmosphere, and solar radiation management (SRM, or sunlight reflection methods), whereby a small percentage of sunlight is reflected back into space to offset warming from greenhouse gases. In this review, we evaluate some of the possible impacts of CDR and SRM on the physical climate and their subsequent influence on ecosystems, including the risks and uncertainties associated with new kinds of purposeful perturbations to Earth. Specifically, we find evidence that, if implemented successfully, some CDR methods and continue use of some SRM methods) could alleviate some of the deleterious ecosystem impacts associated with climate changes that might occur in the foreseeable future.

  17. Impact of geo-engineering on the ion composition of the stratosphere

    NASA Astrophysics Data System (ADS)

    Beig, Gufran

    2008-05-01

    A remedy called ``geo-engineering solution'' has been recently proposed by some scientists to handle the global warming problem through injection of sulfates high aloft into the stratosphere. However, this idea may have some other side impacts. We have investigated the perturbation caused by geo-engineering solution on the stratospheric charged species using a coupled neutral-ion photochemical model. Model calculations indicate additional production of sulfuric acid immediately after the injection which further leads to increased abundance of heavy negative ion family by several orders of magnitude over the ambient. After 2 months, most of the H2SO4 vapor condensed to H2SO4 aerosols and the density of charged aerosol increases several folds and the effect spread further in the tropics. The perturbation in ionic species spread globally after about 1 year but became weaker in magnitude. The ion perturbation has implications on the electrical properties of the atmospheric medium.

  18. A Consideration of the Health and Environmental Risks/Effects of Geoengineering

    NASA Astrophysics Data System (ADS)

    Hemming, B. L.; Felgenhauer, T. N.; Miller, C. A.

    2014-12-01

    The views expressed in this abstract are those of the authors and do not necessarily represent the views or policies of the U.S. Environmental Protection Agency. A number of geoengineering strategies have been proposed and, to date, a few are being seriously investigated as possible approaches to reducing the degree of climate change. Whether under the broad rubrics of solar radiation management (SRM) or carbon dioxide removal (CDR), these projects would involve major, intentional intervention in the world's climate. Even if successful in off-setting the global radiative imbalance induced by human activities, it is not at all clear how well humans and the ecosystems upon which they depend will weather the climate system perturbations induced by the implementation of a large-scale geoengineering program. It is reasonable to expect that such perturbations could exacerbate the existing health and environmental consequences of anthropogenic climate change at large and small scales, or create entirely new ones. An accounting of the derivative physical and biological effects of consequence to human health and ecosystems welfare that may result from the use of geoengineering is a necessary part of any policy-relevant analysis. However, the scientific understanding required to quantitatively assess these potential impacts is absent in most cases, and still nascent in others. Furthermore, current discussions and existing literature lack the fully integrated "systems" approach required for adequately assessing the short- and long-term impacts of geoengineering strategies on ecosystems and human populations. We present an overview of critical science questions, including broad questions concerning the potential response of the complex earth system to further human interference and those concerning potential impacts to local environmental metrics such as air and water quality and ecosystem viability.

  19. Microphysical and radiative changes in cirrus clouds by geoengineering the stratosphere

    NASA Astrophysics Data System (ADS)

    Cirisan, A.; Spichtinger, P.; Luo, B. P.; Weisenstein, D. K.; Wernli, H.; Lohmann, U.; Peter, T.

    2013-05-01

    In the absence of tangible progress in reducing greenhouse gas emissions, the implementation of solar radiation management has been suggested as measure to stop global warming. Here we investigate the impacts on northern midlatitude cirrus from continuous SO2emissions of 2-10 Mt/a in the tropical stratosphere. Transport of geoengineering aerosols into the troposphere was calculated along trajectories based on ERA Interim reanalyses using ozone concentrations to quantify the degree of mixing of stratospheric and tropospheric air termed "troposphericity". Modeled size distributions of the geoengineered H2SO4-H2O droplets have been fed into a cirrus box model with spectral microphysics. The geoengineering is predicted to cause changes in ice number density by up to 50%, depending on troposphericity and cooling rate. We estimate the resulting cloud radiative effects from a radiation transfer model. Complex interplay between the few large stratospheric and many small tropospheric H2SO4-H2O droplets gives rise to partly counteracting radiative effects: local increases in cloud radiative forcing up to +2 W/m2for low troposphericities and slow cooling rates, and decreases up to -7.5 W/m2for high troposphericities and fast cooling rates. The resulting mean impact on the northern midlatitudes by changes in cirrus is predicted to be low, namely <1% of the intended radiative forcing by the stratospheric aerosols. This suggests that stratospheric sulphate geoengineering is unlikely to have large microphysical effects on the mean cirrus radiative forcing. However, this study disregards feedbacks, such as temperature and humidity changes in the upper troposphere, which must be examined separately.

  20. A new Geoengineering Model Intercomparison Project (GeoMIP) experiment designed for climate and chemistry models

    NASA Astrophysics Data System (ADS)

    Tilmes, S.; Mills, M. J.; Niemeier, U.; Schmidt, H.; Robock, A.; Kravitz, B.; Lamarque, J.-F.; Pitari, G.; English, J. M.

    2014-08-01

    A new Geoengineering Model Intercomparison Project (GeoMIP) experiment "G4 specified stratospheric aerosols" (short name: G4SSA) is proposed to investigate the impact of stratospheric aerosol geoengineering on atmospheric composition, climate, and the environment. In contrast to the earlier G4 GeoMIP experiment, which requires an emission of sulphur dioxide (SO2) into the model, a prescribed aerosol forcing file is provided to the community, to be consistently applied to future model experiments between 2020 and 2100. This stratospheric aerosol distribution, with a total burden of about 2 Tg S has been derived using the ECHAM5-HAM microphysical model, based on a continuous annual tropical emission of 8 Tg SO2 year-1. A ramp-up of geoengineering in 2020 and a ramp-down in 2070 over a period of two years are included in the distribution, while a background aerosol burden should be used for the last 3 decades of the experiment. The performance of this experiment using climate and chemistry models in a multi-model comparison framework will allow us to better understand the significance of the impact of geoengineering and the abrupt termination after 50 years on climate and composition of the atmosphere in a changing environment. The zonal and monthly mean stratospheric aerosol input dataset is available at https://www2.acd.ucar.edu/gcm/geomip-g4-specified-stratospheric-aerosol-data-set.

  1. Efficacy of geoengineering to limit 21st century sea-level rise

    PubMed Central

    Moore, J. C.; Jevrejeva, S.; Grinsted, A.

    2010-01-01

    Geoengineering has been proposed as a feasible way of mitigating anthropogenic climate change, especially increasing global temperatures in the 21st century. The two main geoengineering options are limiting incoming solar radiation, or modifying the carbon cycle. Here we examine the impact of five geoengineering approaches on sea level; SO2 aerosol injection into the stratosphere, mirrors in space, afforestation, biochar, and bioenergy with carbon sequestration. Sea level responds mainly at centennial time scales to temperature change, and has been largely driven by anthropogenic forcing since 1850. Making use a model of sea-level rise as a function of time-varying climate forcing factors (solar radiation, volcanism, and greenhouse gas emissions) we find that sea-level rise by 2100 will likely be 30 cm higher than 2000 levels despite all but the most aggressive geoengineering under all except the most stringent greenhouse gas emissions scenarios. The least risky and most desirable way of limiting sea-level rise is bioenergy with carbon sequestration. However aerosol injection or a space mirror system reducing insolation at an accelerating rate of 1 W m-2 per decade from now to 2100 could limit or reduce sea levels. Aerosol injection delivering a constant 4 W m-2 reduction in radiative forcing (similar to a 1991 Pinatubo eruption every 18 months) could delay sea-level rise by 40–80 years. Aerosol injection appears to fail cost-benefit analysis unless it can be maintained continuously, and damage caused by the climate response to the aerosols is less than about 0.6% Global World Product. PMID:20798055

  2. Regional climate responses to geoengineering with tropical and Arctic SO2 injections

    NASA Astrophysics Data System (ADS)

    Robock, Alan; Oman, Luke; Stenchikov, Georgiy L.

    2008-08-01

    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 SO2 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 if 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.

  3. A simple, physically-based method for evaluating the economic costs of geo-engineering schemes

    NASA Astrophysics Data System (ADS)

    Garrett, T. J.

    2009-04-01

    The consumption of primary energy (e.g coal, oil, uranium) by the global economy is done in expectation of a return on investment. For geo-engineering schemes, however, the relationship between the primary energy consumption required and the economic return is, at first glance, quite different. The energy costs of a given scheme represent a removal of economically productive available energy to do work in the normal global economy. What are the economic implications of the energy consumption associated with geo-engineering techniques? I will present a simple thermodynamic argument that, in general, real (inflation-adjusted) economic value has a fixed relationship to the rate of global primary energy consumption. This hypothesis will be shown to be supported by 36 years of available energy statistics and a two millennia period of statistics for global economic production. What is found from this analysis is that the value in any given inflation-adjusted 1990 dollar is sustained by a constant 9.7 +/- 0.3 milliwatts of global primary energy consumption. Thus, insofar as geo-engineering is concerned, any scheme that requires some nominal fraction of continuous global primary energy output necessitates a corresponding inflationary loss of real global economic value. For example, if 1% of global energy output is required, at today's consumption rates of 15 TW this corresponds to an inflationary loss of 15 trillion 1990 dollars of real value. The loss will be less, however, if the geo-engineering scheme also enables a demonstrable enhancement to global economic production capacity through climate modification.

  4. News and Views: Missing the boat; Wanted: geophysics for teachers; Government seeks geo-engineering information

    NASA Astrophysics Data System (ADS)

    2008-08-01

    The Institute of Physics is seeking short summaries of geophysics topics to support school teachers, in a move aimed at boosting the teaching and awareness of geophysics in schools. The UK government Department of Innovation, Universities, Science and Skills is seeking information on geo-engineering as a case study within its major enquiry into engineering. The field described by the DUISS is broad and covers areas in which geophysicists may be working and in a position to supply useful information.

  5. Geoengineering of stratocumulus decks to counterbalance global warming: Pros, Cons, Side-Effects and time-scales

    NASA Astrophysics Data System (ADS)

    Haywood, J.; Jones, A.; Boucher, O.; Jones, C. D.

    2009-04-01

    Anthropogenic emissions of carbon dioxide from fossil-fuel burning are the primary cause of global warming and the projected rate of temperature change is very likely to increase in the future. Many geoengineering solutions have recently been suggested to reduce global warming. Here we use a state-of-the-science general circulation model of the climate to investigate the climatic impact of geoengineering via modifying stratocumulus decks. The model's climate is more than twice as sensitive to modification of the South Pacific stratocumulus area compared with the North Pacific or South Atlantic stratocumulus area. If all stratocumulus decks were geoengineered, the model suggests possibly significant precipitation reductions over South America, North America and over Europe and Asia. Thus the use of geographically inhomogeneous radiative forcing mechanisms to counterbalance global warming induces distinct geographic responses in temperature and precipitation that may be very detrimental to some areas of the Earth. Additionally, we find that the cessation of geoengineering of these regions leads to rapid (10-20 years) recovery of the climate system to a non-geoengineered state. We have used a simple climate model to investigate more generally how delays in reducing CO2 emissions affect stabilisation scenarios leading to overshooting of a target concentration pathway. We show that if geoengineering alone is used to compensate for the delay in reducing CO2 emissions, such an option needs to be sustained for centuries even though the period of overshooting emissions may only last for a few decades. If geoengineering is used for a shorter period, it has to be associated with emission reductions significantly larger than those required to stabilise CO2 without overshooting the target. In the presence of a strong climate-carbon cycle feedback the required emission reductions are even more drastic.

  6. Systemic effects of geoengineering by terrestrial carbon dioxide removal on carbon related planetary boundaries

    NASA Astrophysics Data System (ADS)

    Heck, Vera; Donges, Jonathan; Lucht, Wolfgang

    2015-04-01

    The planetary boundaries framework as proposed by Rockström et al. (2009) provides guidelines for ecological boundaries, the transgression of which is likely to result in a shift of Earth system functioning away from the relatively stable Holocene state. As the climate change boundary is already close to be transgressed, several geoengineering (GE) methods are discussed, aiming at a reduction of atmospheric carbon concentrations to control the Earth's energy balance. One of the proposed GE methods is carbon extraction from the atmosphere via biological carbon sequestration. In case mitigation efforts fail to substantially reduce greenhouse gas emissions, this form of GE could act as potential measure to reduce atmospheric carbon dioxide concentrations. We here study the possible influences of human interactions in the Earth system on carbon related planetary boundaries in the form of geoengineering (terrestrial carbon dioxide removal). We use a conceptual model specifically designed to investigate fundamental carbon feedbacks between land, ocean and atmosphere (Anderies et al., 2013) and modify it to include an additional geoengineering component. With that we analyze the existence and stability of a safe operating space for humanity, which is here conceptualized in three of the 9 proposed dimensions, namely climate change, ocean acidification and land-use. References: J. M. Anderies et al., The topology of non-linear global carbon dynamics: from tipping points to planetary boundaries. Environ. Res. Lett., 8(4):044048 (2013) J. Rockström et al., A safe operating space for humanity. Nature 461 (7263), 472-475 (2009)

  7. Geo-Engineering Gone Awry - A New Partial Solution to Fermis Paradox

    NASA Astrophysics Data System (ADS)

    Cirkovic, Milan M.; Cathcart, Richard B.

    Another partial solution of Fermi's famous paradox is proposed, based on our increased understanding of geophysics, geo-engineering, and climatology. It has been claimed in the recent astrobiological literature (for instance, in the recent controversial “rare Earth” theory of Ward and Brownlee), that geological activity of a terrestrial planet is an important precondition for the emergence of complex metazoan life forms. Technological civilizations arising on such planets will be, at some point of their histories or another, tempted to embark upon massive geo-engineering projects. If, for some reasons only very recently understood, large-scale geo-engineering is in fact much more dangerous than previously thought, the scenario in which at least some of the extraterrestrial civilizations in the Milky Way self-destruct in this manner gains plausibility. In addition, we speculate on possible reasons, both physical and culturological, which could make such a threat even more pertinent on an average Galactic terrestrial planet than on Earth.

  8. Climate Model Response from the Geoengineering Model Intercomparison Project (GeoMIP)

    SciTech Connect

    Kravitz, Benjamin S.; Caldeira, Ken; Boucher, Olivier; Robock, Alan; Rasch, Philip J.; Alterskjaer, Kari; Bou Karam, Diana; Cole, Jason N.; Curry, Charles L.; Haywood, J.; Irvine, Peter; Ji, Duoying; Jones, A.; Kristjansson, J. E.; Lunt, Daniel; Moore, John; Niemeier, Ulrike; Schmidt, Hauke; Schulz, M.; Singh, Balwinder; Tilmes, S.; Watanabe, Shingo; Yang, Shuting; Yoon, Jin-Ho

    2013-08-09

    Solar geoengineering—deliberate reduction in the amount of solar radiation retained by the Earth—has been proposed as a means of counteracting some of the climatic effects of anthropogenic greenhouse gas emissions. We present results from Experiment G1 of the Geoengineering Model Intercomparison Project, in which 12 climate models have simulated the climate response to an abrupt quadrupling of CO2 from preindustrial concentrations brought into radiative balance via a globally uniform reduction in insolation. Models show this reduction largely offsets global mean surface temperature increases due to quadrupled CO2 concentrations and prevents 97% of the Arctic sea ice loss that would otherwise occur under high CO2 levels but, compared to the preindustrial climate, leaves the tropics cooler (-0.3 K) and the poles warmer (+0.8 K). Annual mean precipitation minus evaporation anomalies for G1 are less than 0.2mmday-1 in magnitude over 92% of the globe, but some tropical regions receive less precipitation, in part due to increased moist static stability and suppression of convection. Global average net primary productivity increases by 120% in G1 over simulated preindustrial levels, primarily from CO2 fertilization, but also in part due to reduced plant heat stress compared to a high CO2 world with no geoengineering. All models show that uniform solar geoengineering in G1 cannot simultaneously return regional and global temperature and hydrologic cycle intensity to preindustrial levels.

  9. 35th Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Boesiger, Edward A. (Compiler); Doty, Laura W. (Technical Monitor)

    2001-01-01

    The proceedings of the 35th Aerospace Mechanisms Symposium are reported. Ames Research Center hosted the conference, which was held at the Four Points Sheraton, Sunnyvale, California, on May 9-11, 2001. The symposium was sponsored by the Mechanisms Education Association. Technology areas covered included bearings and tribology; pointing, solar array, and deployment mechanisms; and other mechanisms for spacecraft and large space structures.

  10. 41st Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Boesiger, Edward A. (Editor)

    2012-01-01

    The proceedings of the 41st Aerospace Mechanisms Symposium are reported. JPL hosted the conference, which was held in Pasadena Hilton, Pasadena, California on May 16-18, 2012. Lockheed Martin Space Systems cosponsored the symposium. Technology areas covered include gimbals and positioning mechanisms, components such as hinges and motors, CubeSats, tribology, and Mars Science Laboratory mechanisms.

  11. 33rd Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Boesiger, Edward A. (Compiler); Litty, Edward C. (Compiler); Sevilla, Donald R. (Compiler)

    1999-01-01

    The proceedings of the 33rd Aerospace Mechanisms Symposium are reported. JPL hosted the conference, which was held at the Pasadena Conference and Exhibition Center, Pasadena, California, on May 19-21, 1999. Lockheed Martin Missiles and Space cosponsored the symposium. Technology areas covered include bearings and tribology; pointing, solar array and deployment mechanisms; orbiter/space station; and other mechanisms for spacecraft.

  12. RICIS Symposium 1988

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Integrated Environments for Large, Complex Systems is the theme for the RICIS symposium of 1988. Distinguished professionals from industry, government, and academia have been invited to participate and present their views and experiences regarding research, education, and future directions related to this topic. Within RICIS, more than half of the research being conducted is in the area of Computer Systems and Software Engineering. The focus of this research is on the software development life-cycle for large, complex, distributed systems. Within the education and training component of RICIS, the primary emphasis has been to provide education and training for software professionals.

  13. IAU Symposium 317 Summary

    NASA Astrophysics Data System (ADS)

    Gratton, Raffaele G.

    2016-08-01

    The assembly of the halo yields fundamental information on the formation and evolution of galaxies: this was quite exhaustively discussed at this very important symposium. I present a brief personal summary of the meeting, outlining those points that I found more exciting and suggestive. I also remarked a few areas that were possibly not enough expanded. I found this research field extremely interesting and I think there are great expectations for new developments in the next few years, thanks to the new large spectroscopic surveys and the ESA GAIA satellite.

  14. A cooperative clinical study of methadyl acetate. II. Friday-only regimen.

    PubMed

    Ling, W; Klett, J C; Gillis, R D

    1980-08-01

    We conducted an open clinical trial of the feasibility of maintaining heroin addicts by administering methadone hydrochloride on Monday through Thursday, methadyl acetate on Friday, and no drug at all on Saturday or Sunday. Sixty-five patients from four participating clinics were randomly assigned to this schedule and another 71 to a daily methadone comparison group. The patient sample consisted of heroin addicts previously stabilized on a maintenance regimen of methadone. The starting dose of methadyl acetate was identical to the previously established dose of methadone but was flexible within limites thereafter. A greater number of patients in the methadyl acetate group failed to complete the full 40 weeks of the study, particularly because they claimed the medication was not holding. Although this particular use of methadyl acetate on Friday to provide a drug-free weekend does not appear to be widely applicable clinically, the fact that at least some patients in the methadyl acetate group tolerated the schedule with little or no illicit drug use or obvious discomfort suggests that the strategy is viable and should not be discarded. PMID:7406654

  15. The first Brazilian Dinosaur Symposium

    NASA Astrophysics Data System (ADS)

    dos Anjos Candeiro, Carlos Roberto; da Silva Marinho, Thiago

    2015-08-01

    The 1st Brazilian Dinosaur Symposium gathered paleontologists, geologists, and paleoartists in the city of Ituiutaba, Minas Gerais State, Brazil, from April 21st to 24th, 2013. The Dinosaur Symposium in the Pontal Campus of the Universidade Federal de Uberlândia, Minas Gerais State, Brazil provided an opportunity to share many new results of dinosaur research being conducted around the world. The symposium coincided with a new dawn of scientific advances in dinosaur paleontology further expanding its importance, interest and credibility worldwide.

  16. Women's technical and professional symposium

    SciTech Connect

    Budil, K; Mack, L

    1999-10-01

    This is the fourth LLNL-sponsored Women's Technical and Professional Symposium. This year's theme: ''Excellence through the Millennium,'' focuses on the cutting edge work being done at LLNL and the many contributions of women to our science and technology mission. We hope this Symposium gives each person attending a better idea of the broad scope of the Laboratory's mission and their place within the organization. It is easy to lose sight of the fact that we all work in support of science and technology despite the diversity of our experience. This Symposium provides an opportunity to reflect on our past and to begin to plan our future.

  17. Simulation of how a geo-engineering intervention to restore arctic sea ice might work in practice

    NASA Astrophysics Data System (ADS)

    Jackson, L. S.; Crook, J. A.; Forster, P.; Jarvis, A.; Leedal, D.; Ridgwell, A. J.; Vaughan, N.

    2013-12-01

    The declining trend in annual minimum Arctic sea ice coverage and years of more pronounced drops like 2007 and 2012 raise the prospect of an Arctic Ocean largely free of sea ice in late summer and the potential for a climate crisis or emergency. In a novel computer simulation, we treated one realisation of a climate model (HadGEM2) as the real world and tried to restore its Arctic sea ice by the rapid deployment of geo-engineering with emission of SO2 into the Arctic stratosphere. The objective was to restore the annual minimum Arctic sea ice coverage to levels seen in the late twentieth century using as little geo-engineering as possible. We took intervention decisions as one might do in the real world: by committee, using a limited set of uncertain 'observations' from our simulated world and using models and control theory to plan the best intervention strategy for the coming year - so learning as we went and being thrown off course by future volcanoes and technological breakdowns. Uncertainties in real world observations were simulated by applying noise to emerging results from the climate model. Volcanic forcing of twenty-first century climate was included with the timing and magnitude of the simulated eruptions unknown by the 'geo-engineers' until after the year of the eruption. Monitoring of Arctic sea ice with the option to intervene with SO2 emissions started from 2018 and continued to 2075. Simulated SO2 emissions were made in January-May each year at a latitude of 79o N and an altitude within the range of contemporary tanker aircraft. The magnitude of emissions was chosen annually using a model predictive control process calibrated using results from CMIP5 models (excluding HadGEM2), using the simplified climate model MAGICC and assimilation of emerging annual results from the HadGEM2 'real world'. We found that doubts in the minds of the 'geo-engineers' of the effectiveness and the side effects of their past intervention, and the veracity of the models

  18. A comparison of temperature and precipitation responses to different Earth radiation management geoengineering schemes

    NASA Astrophysics Data System (ADS)

    Crook, J. A.; Jackson, L. S.; Osprey, S. M.; Forster, P. M.

    2015-09-01

    Earth radiation management has been suggested as a way to rapidly counteract global warming in the face of a lack of mitigation efforts, buying time and avoiding potentially catastrophic warming. We compare six different radiation management schemes that use surface, troposphere, and stratosphere interventions in a single climate model in which we projected future climate from 2020 to 2099 based on RCP4.5. We analyze the surface air temperature responses to determine how effective the schemes are at returning temperature to its 1986-2005 climatology and analyze precipitation responses to compare side effects. We find crop albedo enhancement is largely ineffective at returning temperature to its 1986-2005 climatology. Desert albedo enhancement causes excessive cooling in the deserts and severe shifts in tropical precipitation. Ocean albedo enhancement, sea-spray geoengineering, cirrus cloud thinning, and stratospheric SO2 injection have the potential to cool more uniformly, but cirrus cloud thinning may not be able to cool by much more than 1 K globally. We find that of the schemes potentially able to return surface air temperature to 1986-2005 climatology under future greenhouse gas warming, none has significantly less severe precipitation side effects than other schemes. Despite different forcing patterns, ocean albedo enhancement, sea-spray geoengineering, cirrus cloud thinning, and stratospheric SO2 injection all result in large scale tropical precipitation responses caused by Hadley cell changes and land precipitation changes largely driven by thermodynamic changes. Widespread regional scale changes in precipitation over land are significantly different from the 1986-2005 climatology and would likely necessitate significant adaptation despite geoengineering.

  19. Editorial - A critical perspective on geo-engineering for eutrophication management in lakes.

    PubMed

    Lürling, Miquel; Mackay, Eleanor; Reitzel, Kasper; Spears, Bryan M

    2016-06-15

    Eutrophication is the primary worldwide water quality issue. Reducing excessive external nutrient loading is the most straightforward action in mitigating eutrophication, but lakes, ponds and reservoirs often show little, if any, signs of recovery in the years following external load reduction. This is due to internal cycling of phosphorus (P). Geo-engineering, which we can here define as activities intervening with biogeochemical cycles to control eutrophication in inland waters, represents a promising approach, under appropriate conditions, to reduce P release from bed sediments and cyanobacteria accumulation in surface waters, thereby speeding up recovery. In this overview, we draw on evidence from this special issue Geoengineering in Lakes, and on supporting literature to provide a critical perspective on the approach. We demonstrate that many of the strong P sorbents in the literature will not be applicable in the field because of costs and other constraints. Aluminium and lanthanum modified compounds are among the most effective compounds for targeting P. Flocculants and ballast compounds can be used to sink cyanobacteria, in the short term. We emphasize that the first step in managing eutrophication is a system analysis that will reveal the main water and P flows and the biological structure of the waterbody. These site specific traits can be significant confounding factors dictating successful eutrophication management. Geo-engineering techniques, considered collectively, as part of a tool kit, may ensure successful management of eutrophication through a range of target effects. In addition, novel developments in modified zeolites offer simultaneous P and nitrogen control. To facilitate research and reduce the delay from concept to market a multi-national centre of excellence is required. PMID:27039034

  20. Radiative and climate impacts of a large volcanic eruption during stratospheric sulfur geoengineering

    NASA Astrophysics Data System (ADS)

    Laakso, A.; Kokkola, H.; Partanen, A.-I.; Niemeier, U.; Timmreck, C.; Lehtinen, K. E. J.; Hakkarainen, H.; Korhonen, H.

    2015-08-01

    Both explosive volcanic eruptions, which emit sulfur dioxide into the stratosphere, and stratospheric geoengineering via sulfur injections can potentially cool the climate by increasing the amount of scattering particles in the atmosphere. Here we employ a global aerosol-climate model and an earth system model to study the radiative and climate impacts of an erupting volcano during solar radiation management (SRM). According to our simulations, the radiative impacts of an eruption and SRM are not additive: in the simulated case of concurrent eruption and SRM, the peak increase in global forcing is about 40 % lower compared to a corresponding eruption into a clean background atmosphere. In addition, the recovery of the stratospheric sulfate burden and forcing was significantly faster in the concurrent case since the sulfate particles grew larger and thus sedimented faster from the stratosphere. In our simulation where we assumed that SRM would be stopped immediately after a volcano eruption, stopping SRM decreased the overall stratospheric aerosol load. For the same reasons, a volcanic eruption during SRM lead to only about 1/3 of the peak global ensemble-mean cooling compared to an eruption under unperturbed atmospheric conditions. Furthermore, the global cooling signal was seen only for 12 months after the eruption in the former scenario compared to over 40 months in the latter. In terms of the global precipitation rate, we obtain a 36 % smaller decrease in the first year after the eruption and again a clearly faster recovery in the concurrent eruption and SRM scenario. We also found that an explosive eruption could lead to significantly different regional climate responses depending on whether it takes place during geoengineering or into an unperturbed background atmosphere. Our results imply that observations from previous large eruptions, such as Mt Pinatubo in 1991, are not directly applicable when estimating the potential consequences of a volcanic eruption

  1. Research symposium proceedings. Final report

    SciTech Connect

    1991-12-31

    THE research symposium was organized to present the cutting edge research for PET by individuals from leading institutions throughout the world. The Institute for Clinical PET (ICP) has focused its annual meeting on the clinical applications of PET.

  2. Global and Regional Climate Responses Solar Radiation Management: Results from a climateprediction.net Geoengineering Experiment

    NASA Astrophysics Data System (ADS)

    Ricke, Katharine; Allen, Myles; Ingram, William; Keith, David; Granger Morgan, M.

    2010-05-01

    To date modeling studies suggest that, while significant hydrological anomalies could result from the artificial addition of reflecting aerosols in the stratosphere for the purpose of solar radiation management (SRM), even at the regional level such a geoengineered world would bear a much closer resemblance to a low CO2 world, than to an unmodified high CO2 world. These previous modeling studies have generally compared one or two SRM forcing scenarios to various business-as-usual controls. However, such approaches cannot provide much information about regional sensitivities to the levels of SRM that might realistically result. Should engaging in SRM every be seriously contemplated, such regional analysis of a range of realistic scenarios will be an essential input to any process of geopolitical decision-making. Here we present the results from a large-ensemble experiment that used the HadCM3L GCM, implemented through climateprediction.net. The analysis examines 135 globally-uniform stratospheric optical depth modification scenarios designed to stabilize global temperatures under SRES A1B. Scenarios were tested using ten-member subensembles which made small perturbations to initial conditions. All simulations use identical standard settings of model physics parameters and are initiated from historically-forced runs from 1920-2005. A total of 7,331 simulations of the years 2000-2080 were performed for this experiment using computing resources donated by the general public. Our analysis of regional temperature and precipitation anomalies, normalized to account for variability, shows that SRM compensations for anthropogenic greenhouse gas forcing do generally return regional climates closer to their baseline climate states than the no-geoengineering, business-as-usual scenarios. However, we find that the magnitudes and sensitivities of regional responses to this type of activity, as modeled in HadCM3L, are highly variable. As the amount of SRM increases to compensate

  3. A multi-model assessment of the efficacy of sea spray geoengineering

    NASA Astrophysics Data System (ADS)

    Pringle, K. J.; Carslaw, K. S.; Fan, T.; Mann, G. W.; Hill, A.; Stier, P.; Zhang, K.; Tost, H.

    2012-03-01

    Artificially increasing the albedo of marine clouds by the mechanical emission of sea spray aerosol has been proposed as a geoengineering technique to slow the warming caused by anthropogenic greenhouse gases. A previous global model study found that only modest increases and sometimes even decreases in cloud drop number (CDN) concentrations would result from plausible emission scenarios. Here we extend that work to examine the conditions under which decreases in CDN can occur, and use three independent global models to quantify maximum achievable CDN changes. We find that decreases in CDN can occur when at least three of the following conditions are met: the injected particle number is <100 cm-3, the injected diameter is >250-300 nm, the background aerosol loading is large (≥150 cm-3) and the in-cloud updraught velocity is low (<0.2 ms-1). With lower background loadings and/or increased updraught velocity, significant increases in CDN can be achieved. None of the global models predict a decrease in CDN as a result of geoengineering, although there is considerable diversity in the calculated efficiency of geoengineering, which arises from the diversity in the simulated background aerosol distributions. All three models show a small dependence of geoengineering efficiency on the injected particle size and the geometric standard deviation of the injected mode. However, the achievability of significant cloud drop enhancements is strongly dependent on the cloud updraught speed. With an updraught speed of 0.1 ms-1 a global mean CDN of 375 cm-3 (previously estimated to cancel the forcing caused by CO2 doubling) is achievable in only about 50 % of cloudy grid boxes irrespective of the amount of aerosol injected. But at 0.2 ms-1 a CDN of 375-3 becomes achievable everywhere. Updraught speeds of less than 0.2 ms-1 are common in low-level clouds. Thus, a cloud drop concentration of 375 cm-3 cannot be attained uniformly, regardless of the number of injected particles.

  4. The VLT Opening Symposium

    NASA Astrophysics Data System (ADS)

    1999-02-01

    Scientists Meet in Antofagasta to Discuss Front-Line Astrophysics To mark the beginning of the VLT era, the European Southern Observatory is organizing a VLT Opening Symposium which will take place in Antofagasta (Chile) on 1-4 March 1999, just before the start of regular observations with the ESO Very Large Telescope on April 1, 1999. The Symposium occupies four full days and is held on the campus of the Universidad Catolica del Norte. It consists of plenary sessions on "Science in the VLT Era and Beyond" and three parallel Workshops on "Clusters of Galaxies at High Redshift" , "Star-way to the Universe" and "From Extrasolar Planets to Brown Dwarfs" . There will be many presentations of recent work at the major astronomical facilities in the world. The meeting provides a very useful forum to discuss the latest developments and, in this sense, contributes to the planning of future research with the VLT and other large telescopes. The symposium will be opened with a talk by the ESO Director General, Prof. Riccardo Giacconi , on "Paranal - an observatory for the 21st century". It will be followed by reports about the first scientific results from the main astronomical instruments on VLT UT1, FORS1 and ISAAC. The Symposium participants will see the VLT in operation during special visits to the Paranal Observatory. Press conferences are being arranged each afternoon to inform about the highlights of the conference. After the Symposium, there will be an Official Inauguration Ceremony at Paranal on 5 March Contributions from ESO ESO scientists will make several presentations at the Symposium. They include general reviews of various research fields as well as important new data and results from the VLT that show the great potential of this new astronomical facility. Some of the recent work is described in this Press Release, together with images and spectra of a large variety of objects. Note that all of these data will soon become publicly available via the VLT Archive

  5. 30th Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Bradley, Obie H., Jr. (Compiler); Rogers, John F. (Compiler)

    1996-01-01

    The proceedings of the 30th Aerospace Mechanisms Symposium are reported. NASA Langley Research Center hosted the proceedings held at the Radisson Hotel in Hampton, Virginia on May 15-17, 1996, and Lockheed Martin Missiles and Space Company, Inc. co-sponsored the symposium. Technological areas covered include bearings and tribology; pointing, solar array, and deployment mechanisms; orbiter/space station; and other mechanisms for spacecraft.

  6. LHC Nobel Symposium Proceedings

    NASA Astrophysics Data System (ADS)

    Ekelöf, Tord

    2013-12-01

    In the summer of 2012, a great discovery emerged at the Large Hadron Collider (LHC) at CERN in Geneva. A plethora of new precision data had already by then been collected by the ATLAS and CMS experiments at LHC, providing further extensive support for the validity of the Standard Model of particle physics. But what now appeared was the first evidence for what was not only the last unverified prediction of the Standard Model, but also perhaps the most decisive one: the prediction made already in 1964 of a unique scalar boson required by the theory of François Englert and Peter Higgs on how fundamental particles acquire mass. At that moment in 2012, it seemed particularly appropriate to start planning a gathering of world experts in particle physics to take stock of the situation and try to answer the challenging question: what next? By May 2013, when the LHC Nobel Symposium was held at the Krusenberg Mansion outside Uppsala in Sweden, the first signs of a great discovery had already turned into fully convincing experimental evidence for the existence of a scalar boson of mass about 125 GeV, having properties compatible with the 50-year-old prediction. And in October 2013, the evidence was deemed so convincing that the Swedish Royal Academy of Sciences awarded the Nobel Prize in Physics to Englert and Higgs for their pioneering work. At the same time the search at the LHC for other particles, beyond those predicted by the Standard Model, with heavier masses up to—and in some cases beyond—1 TeV, had provided no positive result. The triumph of the Standard Model seems resounding, in particular because the mass of the discovered scalar boson is such that, when identified with the Higgs boson, the Standard Model is able to provide predictions at energies as high as the Planck mass, although at the price of accepting that the vacuum would be metastable. However, even if there were some feelings of triumph, the ambience at the LHC Nobel Symposium was more one of

  7. Impacts of light shading and nutrient enrichment geo-engineering approaches on the productivity of a stratified, oligotrophic ocean ecosystem.

    PubMed

    Hardman-Mountford, Nick J; Polimene, Luca; Hirata, Takafumi; Brewin, Robert J W; Aiken, Jim

    2013-12-01

    Geo-engineering proposals to mitigate global warming have focused either on methods of carbon dioxide removal, particularly nutrient fertilization of plant growth, or on cooling the Earth's surface by reducing incoming solar radiation (shading). Marine phytoplankton contribute half the Earth's biological carbon fixation and carbon export in the ocean is modulated by the actions of microbes and grazing communities in recycling nutrients. Both nutrients and light are essential for photosynthesis, so understanding the relative influence of both these geo-engineering approaches on ocean ecosystem production and processes is critical to the evaluation of their effectiveness. In this paper, we investigate the relationship between light and nutrient availability on productivity in a stratified, oligotrophic subtropical ocean ecosystem using a one-dimensional water column model coupled to a multi-plankton ecosystem model, with the goal of elucidating potential impacts of these geo-engineering approaches on ecosystem production. We find that solar shading approaches can redistribute productivity in the water column but do not change total production. Macronutrient enrichment is able to enhance the export of carbon, although heterotrophic recycling reduces the efficiency of carbon export substantially over time. Our results highlight the requirement for a fuller consideration of marine ecosystem interactions and feedbacks, beyond simply the stimulation of surface blooms, in the evaluation of putative geo-engineering approaches. PMID:24132201

  8. Impacts of light shading and nutrient enrichment geo-engineering approaches on the productivity of a stratified, oligotrophic ocean ecosystem

    PubMed Central

    Hardman-Mountford, Nick J.; Polimene, Luca; Hirata, Takafumi; Brewin, Robert J. W.; Aiken, Jim

    2013-01-01

    Geo-engineering proposals to mitigate global warming have focused either on methods of carbon dioxide removal, particularly nutrient fertilization of plant growth, or on cooling the Earth's surface by reducing incoming solar radiation (shading). Marine phytoplankton contribute half the Earth's biological carbon fixation and carbon export in the ocean is modulated by the actions of microbes and grazing communities in recycling nutrients. Both nutrients and light are essential for photosynthesis, so understanding the relative influence of both these geo-engineering approaches on ocean ecosystem production and processes is critical to the evaluation of their effectiveness. In this paper, we investigate the relationship between light and nutrient availability on productivity in a stratified, oligotrophic subtropical ocean ecosystem using a one-dimensional water column model coupled to a multi-plankton ecosystem model, with the goal of elucidating potential impacts of these geo-engineering approaches on ecosystem production. We find that solar shading approaches can redistribute productivity in the water column but do not change total production. Macronutrient enrichment is able to enhance the export of carbon, although heterotrophic recycling reduces the efficiency of carbon export substantially over time. Our results highlight the requirement for a fuller consideration of marine ecosystem interactions and feedbacks, beyond simply the stimulation of surface blooms, in the evaluation of putative geo-engineering approaches. PMID:24132201

  9. The Geoengineering Model Intercomparison Project Phase 6 (GeoMIP6): simulation design and preliminary results

    NASA Astrophysics Data System (ADS)

    Kravitz, B.; Robock, A.; Tilmes, S.; Boucher, O.; English, J. M.; Irvine, P. J.; Jones, A.; Lawrence, M. G.; MacCracken, M.; Muri, H.; Moore, J. C.; Niemeier, U.; Phipps, S. J.; Sillmann, J.; Storelvmo, T.; Wang, H.; Watanabe, S.

    2015-06-01

    We present a suite of new climate model experiment designs for the Geoengineering Model Intercomparison Project (GeoMIP). This set of experiments, named GeoMIP6 (to be consistent with the Coupled Model Intercomparison Project Phase 6), builds on the previous GeoMIP simulations, and has been expanded to address several further important topics, including key uncertainties in extreme events, the use of geoengineering as part of a portfolio of responses to climate change, and the relatively new idea of cirrus cloud thinning to allow more longwave radiation to escape to space. We discuss experiment designs, as well as the rationale for those designs, showing preliminary results from individual models when available. We also introduce a new feature, called the GeoMIP Testbed, which provides a platform for simulations that will be performed with a few models and subsequently assessed to determine whether the proposed experiment designs will be adopted as core (Tier 1) GeoMIP experiments. This is meant to encourage various stakeholders to propose new targeted experiments that address their key open science questions, with the goal of making GeoMIP more relevant to a broader set of communities.

  10. The Geoengineering Model Intercomparison Project Phase 6 (GeoMIP6): simulation design and preliminary results

    NASA Astrophysics Data System (ADS)

    Kravitz, B.; Robock, A.; Tilmes, S.; Boucher, O.; English, J. M.; Irvine, P. J.; Jones, A.; Lawrence, M. G.; MacCracken, M.; Muri, H.; Moore, J. C.; Niemeier, U.; Phipps, S. J.; Sillmann, J.; Storelvmo, T.; Wang, H.; Watanabe, S.

    2015-10-01

    We present a suite of new climate model experiment designs for the Geoengineering Model Intercomparison Project (GeoMIP). This set of experiments, named GeoMIP6 (to be consistent with the Coupled Model Intercomparison Project Phase 6), builds on the previous GeoMIP project simulations, and has been expanded to address several further important topics, including key uncertainties in extreme events, the use of geoengineering as part of a portfolio of responses to climate change, and the relatively new idea of cirrus cloud thinning to allow more longwave radiation to escape to space. We discuss experiment designs, as well as the rationale for those designs, showing preliminary results from individual models when available. We also introduce a new feature, called the GeoMIP Testbed, which provides a platform for simulations that will be performed with a few models and subsequently assessed to determine whether the proposed experiment designs will be adopted as core (Tier 1) GeoMIP experiments. This is meant to encourage various stakeholders to propose new targeted experiments that address their key open science questions, with the goal of making GeoMIP more relevant to a broader set of communities.

  11. Climatic impacts of stratospheric geoengineering with sulfate, black carbon and titania injection

    NASA Astrophysics Data System (ADS)

    Jones, Anthony C.; Haywood, James M.; Jones, Andy

    2016-03-01

    In this paper, we examine the potential climatic effects of geoengineering by sulfate, black carbon and titania injection against a baseline RCP8.5 scenario. We use the HadGEM2-CCS model to simulate scenarios in which the top-of-the-atmosphere radiative imbalance due to rising greenhouse gas concentrations is offset by sufficient aerosol injection throughout the 2020-2100 period. We find that the global-mean temperature is effectively maintained at historical levels for the entirety of the period for all three aerosol-injection scenarios, though there is a wide range of side-effects which are discussed in detail. The most prominent conclusion is that although the BC injection rate necessary to produce an equivalent global mean temperature response is much lower, the severity of stratospheric temperature changes (> +70 °C) and precipitation impacts effectively exclude BC from being a viable option for geoengineering. Additionally, while it has been suggested that titania would be an effective particle because of its high scattering efficiency, it also efficiently absorbs solar ultraviolet radiation producing a significant stratospheric warming (> +20 °C). As injection rates and climatic impacts for titania are close to those for sulfate, there appears to be little benefit in terms of climatic influence of using titania when compared to the injection of sulfur dioxide, which has the added benefit of being well-modeled through extensive research that has been carried out on naturally occurring explosive volcanic eruptions.

  12. Sensitivity of Stratospheric Geoengineering with Black Carbon to Aerosol Size and Altitude of Injection

    NASA Technical Reports Server (NTRS)

    Kravitz, Ben; Robock, Alan; Shindell, Drew T.; Miller, Mark A.

    2012-01-01

    Simulations of stratospheric geoengineering with black carbon (BC) aerosols using a general circulation model with fixed sea surface temperatures show that the climate effects strongly depend on aerosol size and altitude of injection. 1 Tg BC/a injected into the lower stratosphere would cause little surface cooling for large radii but a large amount of surface cooling for small radii and stratospheric warming of over 60 C. With the exception of small particles, increasing the altitude of injection increases surface cooling and stratospheric warming. Stratospheric warming causes global ozone loss by up to 50% in the small radius case. The Antarctic shows less ozone loss due to reduction of polar stratospheric clouds, but strong circumpolar winds would enhance the Arctic ozone hole. Using diesel fuel to produce the aerosols is likely prohibitively expensive and infeasible. Although studying an absorbing aerosol is a useful counterpart to previous studies involving sulfate aerosols, black carbon geoengineering likely carries too many risks to make it a viable option for deployment.

  13. Climatic impacts of stratospheric geoengineering with sulfate, black carbon and titania injection

    NASA Astrophysics Data System (ADS)

    Jones, A. C.; Haywood, J. M.; Jones, A.

    2015-11-01

    In this paper, we examine the potential climatic effects of geoengineering by sulfate, black carbon and titania injection against a baseline RCP8.5 scenario. We use the HadGEM2-CCS model to simulate scenarios in which the top-of-the-atmosphere radiative imbalance due to rising greenhouse gas concentrations is offset by sufficient aerosol injection throughout the 2020-2100 period. We find that the global-mean temperature is effectively maintained at historical levels for the entirety of the period for all 3 aerosol-injection scenarios, though there are a wide range of side-effects which are discussed in detail. The most prominent conclusion is that although the BC injection rate necessary to produce an equivalent global mean temperature-response is much lower, the severity of stratospheric temperature changes (> +70 °C) and precipitation impacts effectively exclude BC from being a viable option for geoengineering. Additionally, while it has been suggested that titania would be an effective particle because of its high scattering efficiency, it also efficiently absorbs solar ultraviolet radiation producing a significant stratospheric warming (> +20 °C). As injection rates for titania are close to those for sulfate, there appears little benefit of using titania when compared to injection of sulfur dioxide, which has the added benefit of being well modelled through extensive research that has been carried out on naturally occurring explosive volcanic eruptions.

  14. The Geoengineering Model Intercomparison Project Phase 6 (GeoMIP6). Simulation Design and Preliminary Results

    SciTech Connect

    Kravitz, Benjamin S.; Robock, Alan; Tilmes, S.; Boucher, Olivier; English, J.; Irvine, Peter; Jones, Andrew; Lawrence, M. G.; Maccracken, Michael C.; Muri, Helene O.; Moore, John; Niemeier, Ulrike; Phipps, Steven; Sillmann, Jana; Storelvmo, Trude; Wang, Hailong; Watanabe, Shingo

    2015-10-27

    We present a suite of new climate model experiment designs for the Geoengineering Model Intercomparison Project (GeoMIP). This set of experiments, named GeoMIP6 (to be consistent with the Coupled Model Intercomparison Project Phase 6), builds on the previous GeoMIP project simulations, and has been expanded to address several further important topics, including key uncertainties in extreme events, the use of geoengineering as part of a portfolio of responses to climate change, and the relatively new idea of cirrus cloud thinning to allow more longwave radiation to escape to space. We discuss experiment designs, as well as the rationale for those designs, showing preliminary results from individual models when available. We also introduce a new feature, called the GeoMIP Testbed, which provides a platform for simulations that will be performed with a few models and subsequently assessed to determine whether the proposed experiment designs will be adopted as core (Tier 1) GeoMIP experiments. This is meant to encourage various stakeholders to propose new targeted experiments that address their key open science questions, with the goal of making GeoMIP more relevant to a broader set of communities.

  15. Geoengineering techniques to mitigate climate change: from futuristic to down-to-earth approaches

    NASA Astrophysics Data System (ADS)

    Mills, W. B.

    2006-12-01

    At the present time, strategies to mitigate anthropogenically induced climate change focus on methods intended to decrease emissions of greenhouse gases (GHGs) to the atmosphere in order to prevent atmospheric concentrations of GHGs from reaching dangerous levels. Examples of climate change mitigation strategies include: use higher percentages of low-carbon fuels (such as nuclear); rely more on renewable energy (such as wind); capture and sequester carbon from large stationary sources such as power plants; and increase energy efficiency. Within the past several years, more and more scientists are questioning whether these techniques can be implemented on a global scale quickly enough to avoid dangerous anthropogenic climate change impacts. Further, some signatories to the Kyoto Protocol have already indicated they will not be able to meet their reductions of emissions by the agreed upon date of 2012, and in fact expect to increase their emissions. An important question becomes: Are there other mitigation techniques that could be used in a supplemental manner to help control anthropogenically-induced climate change should those techniques mentioned above fall short? In fact there are a variety of techniques that are commonly called geo-engineering methods (or earth-engineering methods) that could be considered. A number of these techniques were introduced more than a decade ago in an American Academy of Science report published in 1991. However, they but have not received serious attention until recently as scientists have become more concerned about limitations of mitigation strategies presently on the table. In this poster, we will summarize the geo-engineering techniques that have been proposed, both those originally introduced by the National Academy of Science and numerous others that have been developed since then, particularly over the past year or two. We discuss two of these approaches in detail: one is a space-based approach and the other is an earth

  16. 76 FR 22899 - Federal Health IT Strategic Plan: 2011-2015 Open Comment Period Extended Until Friday, May 6

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-25

    ... HUMAN SERVICES Federal Health IT Strategic Plan: 2011-2015 Open Comment Period Extended Until Friday...: Notice. SUMMARY: The Federal Health IT Strategic Plan: 2011-2015 (``the Plan'') ] was posted on the ONC... considered, you must submit your comment via the Federal Health IT Buzz Blog:...

  17. Risk Communication and Public Education in Edmonton, Alberta, Canada on the 10th Anniversary of the "Black Friday" Tornado

    ERIC Educational Resources Information Center

    Blanchard-Boehm, R. Denise; Cook, M. Jeffrey

    2004-01-01

    In July 1997, on the 10th anniversary of the great "Black Friday" Tornado, city officials of Edmonton, the print and broadcast media, agencies dealing in emergency management, and the national weather organisation recounted stories of the 1987, F5 tornado that struck Edmonton on a holiday weekend. The information campaign also presented…

  18. Niobium - Proceedings of the international symposium

    SciTech Connect

    Stuart, H.

    1984-01-01

    This book presents the papers given at a symposium on niobium. Topics considered at the symposium included niobium mining, ore processing, uses, fabrication, microstructure, mechanical properties, physical properties, corrosion, physical radiation effects, and marketing.

  19. The 1986 Get Away Special Experimenter's Symposium

    NASA Technical Reports Server (NTRS)

    Thomas, Lawrence R. (Editor); Mosier, Frances L. (Editor)

    1987-01-01

    The 1986 Get Away Special (GAS) Experimenter's Symposium will provide a formal opportunity for GAS Experimenter's to share the results of their projects. The focus of this symposium is on payloads that will be flown in the future.

  20. Solid Freeform Fabrication Symposium Proceedings

    NASA Astrophysics Data System (ADS)

    Marcus, Harris L.; Beeman, Joseph J.; Barlow, Joel W.; Bourell, David L.; Crawford, Richard H.

    1993-09-01

    This Proceedings of the Fourth Solid Freeform Fabrication Symposium, held at The University of Texas in Austin on August 9-11, 1993, reaffirms the dynamic nature of the research area. The interest shown by researchers over the wide range of disciplines and subdisciplines that make up solid freeform fabrication (SFF) highlight this technical symposium. The speakers addressed problems in computer software, in machine design, materials synthesis and processing, and SFF in integrated manufacturing. The exponential growth in the research, application, and development of SFF approaches was readily apparent from the attendees from industrial users, SFF machine manufacturers, universities, and government. This symposium is the first where real progress toward structurally sound samples and parts was demonstrated as SFF moves from 'feelie' to 'nonstructural' to 'structural' real parts over a range of materials. This advancement in the state-of-the-art of SFF will continue to drive the exponential growth of the area. The excitement amongst the symposium participants will continue to serve as the catalyst for the continued growth and the availability of solid freeform fabrication. The symposium organizers look forward to its being a continued source of technical exchange among the growing body of researchers involved in SFF.

  1. The Schoolwide Symposium: A Model for Learning.

    ERIC Educational Resources Information Center

    Cottingham, Walt

    1999-01-01

    Discusses the first schoolwide symposium at Hendersonville High School (North Carolina) in which, for one week, students and faculty were immersed in the culture and history of the Vietnam War era. Explains that because this first symposium was so successful in gaining student enthusiasm, the school organized three more symposiums. (CMK)

  2. Symposium Promotes Technological Literacy through STEM

    ERIC Educational Resources Information Center

    Havice, Bill; Marshall, Jerry

    2009-01-01

    This article describes a symposium which promotes technological literacy through science, technology, engineering, and mathematics (STEM). The three-day symposium titled, "The Anderson, Oconee, Pickens Symposium on Teaching and Learning STEM Standards for the 21st Century," was held August 4-6, 2008 at the Tri-County Technical College (TCTC)…

  3. 43rd Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Boesiger, Edward A.

    2016-01-01

    The Aerospace Mechanisms Symposium (AMS) provides a unique forum for those active in the design, production and use of aerospace mechanisms. A major focus is the reporting of problems and solutions associated with the development and flight certification of new mechanisms. Sponsored and organized by the Mechanisms Education Association, responsibility for hosting the AMS is shared by the National Aeronautics and Space Administration and Lockheed Martin Space Systems Company (LMSSC). Now in its 43rd symposium, the AMS continues to be well attended, attracting participants from both the U.S. and abroad. The 43rd AMS was held in Santa Clara, California on May 4, 5 and 6, 2016. During these three days, 42 papers were presented. Topics included payload and positioning mechanisms, components such as hinges and motors, CubeSats, tribology, and mechanism testing. Hardware displays during the supplier exhibit gave attendees an opportunity to meet with developers of current and future mechanism components. The high quality of this symposium is a result of the work of many people, and their efforts are gratefully acknowledged. This extends to the voluntary members of the symposium organizing committee representing the eight NASA field centers, LMSSC, and the European Space Agency. Appreciation is also extended to the session chairs, the authors, and particularly the personnel at ARC responsible for the symposium arrangements and the publication of these proceedings. A sincere thank you also goes to the symposium executive committee who is responsible for the year-to-year management of the AMS, including paper processing and preparation of the program. The use of trade names of manufacturers in this publication does not constitute an official endorsement of such products or manufacturers, either expressed or implied, by the National Aeronautics and Space Administration.

  4. Mining and Reclamation Technology Symposium

    SciTech Connect

    None Available

    1999-06-24

    The Mining and Reclamation Technology Symposium was commissioned by the Mountaintop Removal Mining/Valley Fill Environmental Impact Statement (EIS) Interagency Steering Committee as an educational forum for the members of the regulatory community who will participate in the development of the EIS. The Steering Committee sought a balanced audience to ensure the input to the regulatory community reflected the range of perspectives on this complicated and emotional issue. The focus of this symposium is on mining and reclamation technology alternatives, which is one of eleven topics scheduled for review to support development of the EIS. Others include hydrologic, environmental, ecological, and socio-economic issues.

  5. Frank N. Bash Symposium 2015

    NASA Astrophysics Data System (ADS)

    The University of Texas at Austin Department of Astronomy and McDonald Observatory will be hosting the sixth biennial Frank N. Bash Symposium on the topic of New Horizons in Astronomy, October 18-20, 2015, on The University of Texas at Austin campus. This meeting will bring together young researchers at the cutting edge of astronomy and astrophysics, to promote the exchange of research ideas and visions for the future of astronomy. The symposium will focus on invited review talks, and will include discussions and contributed poster papers from postdocs and students.

  6. LHC Symposium 2003: Summary Talk

    SciTech Connect

    Jeffrey A. Appel

    2003-08-12

    This summary talk reviews the LHC 2003 Symposium, focusing on expectations as we prepare to leap over the current energy frontier into new territory. We may learn from what happened in the two most recent examples of leaping into new energy territory. Quite different scenarios appeared in those two cases. In addition, they review the status of the machine and experiments as reported at the Symposium. Finally, I suggest an attitude which may be most appropriate as they look forward to the opportunities anticipated for the first data from the LHC.

  7. Impact of geoengineering with olivine dissolution on the carbon cycle and marine biology

    NASA Astrophysics Data System (ADS)

    Köhler, P.; Abrams, J.; Völker, C.; Wolf-Gladrow, D. A.; Hartmann, J.

    2012-04-01

    We investigate the potential of a specific geoengineering technique: the carbon sequestration by artificially enhanced silicate weathering via the dissolution of olivine. This approach would not only operate against rising temperatures but would also oppose ocean acidification. If details of the marine chemistry are taken into consideration, a new mass ratio of CO2 sequestration per olivine dissolution of about 1 is achieved, 20% smaller than previously assumed. We calculate that this approach has the potential to sequestrate up to 1 Pg of C per year directly, if olivine is distributed as fine powder over land areas of the humid tropics, but this rate is limited by the saturation concentration of silicic acid. These upper limit sequestration rates come at the environmental cost of pH values in the rivers rising to 8.2 in examples for the rivers Amazon and Congo (Köhler et al., 2010). The secondary effects of the input of silicic acid connected with this approach leads in an ecosystem model (ReCOM2.0 in MITgcm) to species shifts aways from the calcifying species towards diatoms, thus altering the biological carbon pumps. Open ocean dissolution of olivine would sequestrate about 1 Pg CO2 per Pg olivine from which about 8% are caused by changes in the biological pumps (increase export of organic matter, decreased export of CaCO3). The chemical impact of open ocean dissolution of olivine (the increased alkalinity input) is therefore less efficient than dissolution on land, but leads due to different chemical impacts to a higher surface ocean pH enhancement to counteract ocean acidification. We finally investigate open ocean dissolution rates of up to 10 Pg olivine per year corresponding to geoengineering rates which might be of interest in the light of expected future emission (e.g. A2 scenario with emissions rising to 30 PgC/yr in 2100 AD). Those rates would still sequestrate only less than 20% of the emission until 2100, but would require that the nowadays available

  8. Radiative and climate impacts of a large volcanic eruption during stratospheric sulfur geoengineering

    NASA Astrophysics Data System (ADS)

    Laakso, A.; Kokkola, H.; Partanen, A.-I.; Niemeier, U.; Timmreck, C.; Lehtinen, K. E. J.; Hakkarainen, H.; Korhonen, H.

    2016-01-01

    Both explosive volcanic eruptions, which emit sulfur dioxide into the stratosphere, and stratospheric geoengineering via sulfur injections can potentially cool the climate by increasing the amount of scattering particles in the atmosphere. Here we employ a global aerosol-climate model and an Earth system model to study the radiative and climate changes occurring after an erupting volcano during solar radiation management (SRM). According to our simulations the radiative impacts of the eruption and SRM are not additive and the radiative effects and climate changes occurring after the eruption depend strongly on whether SRM is continued or suspended after the eruption. In the former case, the peak burden of the additional stratospheric sulfate as well as changes in global mean precipitation are fairly similar regardless of whether the eruption takes place in a SRM or non-SRM world. However, the maximum increase in the global mean radiative forcing caused by the eruption is approximately 21 % lower compared to a case when the eruption occurs in an unperturbed atmosphere. In addition, the recovery of the stratospheric sulfur burden and radiative forcing is significantly faster after the eruption, because the eruption during the SRM leads to a smaller number and larger sulfate particles compared to the eruption in a non-SRM world. On the other hand, if SRM is suspended immediately after the eruption, the peak increase in global forcing caused by the eruption is about 32 % lower compared to a corresponding eruption into a clean background atmosphere. In this simulation, only about one-third of the global ensemble-mean cooling occurs after the eruption, compared to that occurring after an eruption under unperturbed atmospheric conditions. Furthermore, the global cooling signal is seen only for the 12 months after the eruption in the former scenario compared to over 40 months in the latter. In terms of global precipitation rate, we obtain a 36 % smaller decrease in the

  9. The Third International Symposium on Space Terahertz Technology: Symposium proceedings

    NASA Technical Reports Server (NTRS)

    1992-01-01

    Papers from the symposium are presented that are relevant to the generation, detection, and use of the terahertz spectral region for space astronomy and remote sensing of the Earth's upper atmosphere. The program included thirteen sessions covering a wide variety of topics including solid-state oscillators, power-combining techniques, mixers, harmonic multipliers, antennas and antenna arrays, submillimeter receivers, and measurement techniques.

  10. Solar radiation management impacts on agriculture in China: A case study in the Geoengineering Model Intercomparison Project (GeoMIP)

    NASA Astrophysics Data System (ADS)

    Xia, Lili; Robock, Alan; Cole, Jason; Curry, Charles L.; Ji, Duoying; Jones, Andy; Kravitz, Ben; Moore, John C.; Muri, Helene; Niemeier, Ulrike; Singh, Balwinder; Tilmes, Simone; Watanabe, Shingo; Yoon, Jin-Ho

    2014-07-01

    Geoengineering via solar radiation management could affect agricultural productivity due to changes in temperature, precipitation, and solar radiation. To study rice and maize production changes in China, we used results from 10 climate models participating in the Geoengineering Model Intercomparison Project (GeoMIP) G2 scenario to force the Decision Support System for Agrotechnology Transfer (DSSAT) crop model. G2 prescribes an insolation reduction to balance a 1% a-1 increase in CO2 concentration (1pctCO2) for 50 years. We first evaluated the DSSAT model using 30 years (1978-2007) of daily observed weather records and agriculture practices for 25 major agriculture provinces in China and compared the results to observations of yield. We then created three sets of climate forcing for 42 locations in China for DSSAT from each climate model experiment: (1) 1pctCO2, (2) G2, and (3) G2 with constant CO2 concentration (409 ppm) and compared the resulting agricultural responses. In the DSSAT simulations: (1) Without changing management practices, the combined effect of simulated climate changes due to geoengineering and CO2 fertilization during the last 15 years of solar reduction would change rice production in China by -3.0 ± 4.0 megaton (Mt) (2.4 ± 4.0%) as compared with 1pctCO2 and increase Chinese maize production by 18.1 ± 6.0 Mt (13.9 ± 5.9%). (2) The termination of geoengineering shows negligible impacts on rice production but a 19.6 Mt (11.9%) reduction of maize production as compared to the last 15 years of geoengineering. (3) The CO2 fertilization effect compensates for the deleterious impacts of changes in temperature, precipitation, and solar radiation due to geoengineering on rice production, increasing rice production by 8.6 Mt. The elevated CO2 concentration enhances maize production in G2, contributing 7.7 Mt (42.4%) to the total increase. Using the DSSAT crop model, virtually all of the climate models agree on the sign of the responses, even though

  11. Geo-engineering Evaluation with Prime Consideration to Liquefaction Potential for Eskisehir City (Turkey)

    NASA Astrophysics Data System (ADS)

    Koyuncu, N. Pínar; Ulusay, Resat

    In Turkey, cities are growing in importance and urban areas are expanding rapidly. Eskisehir is one of the highly urbanized and industrialized cities of Turkey. In this study, the city is selected for geo-engineering assessments to be considered in future urban planning due to its ground and seismotectonic conditions. Seismic hazard analyses indicated that magnitude of a probable earthquake and PGA associated with the closest fault may be about 6.4 and 300 gal, respectively. Liquefaction assessments suggest that shallow-seated sand layers, particularly near to the meanders of a river flowing through the city have moderate-to-high liquefaction susceptibility. In addition, GIS-aided engineering geological map of the city center are constructed and some recommendations are presented.

  12. Assessing the controllability of Arctic sea ice extent by sulfate aerosol geoengineering

    NASA Astrophysics Data System (ADS)

    Jackson, L. S.; Crook, J. A.; Jarvis, A.; Leedal, D.; Ridgwell, A.; Vaughan, N.; Forster, P. M.

    2015-02-01

    In an assessment of how Arctic sea ice cover could be remediated in a warming world, we simulated the injection of SO2 into the Arctic stratosphere making annual adjustments to injection rates. We treated one climate model realization as a surrogate "real world" with imperfect "observations" and no rerunning or reference to control simulations. SO2 injection rates were proposed using a novel model predictive control regime which incorporated a second simpler climate model to forecast "optimal" decision pathways. Commencing the simulation in 2018, Arctic sea ice cover was remediated by 2043 and maintained until solar geoengineering was terminated. We found quantifying climate side effects problematic because internal climate variability hampered detection of regional climate changes beyond the Arctic. Nevertheless, through decision maker learning and the accumulation of at least 10 years time series data exploited through an annual review cycle, uncertainties in observations and forcings were successfully managed.

  13. The Hydrological Sensitivity to Global Warming and Solar Geoengineering Derived from Thermodynamic Constraints

    SciTech Connect

    Kleidon, Alex; Kravitz, Benjamin S.; Renner, Maik

    2015-01-16

    We derive analytic expressions of the transient response of the hydrological cycle to surface warming from an extremely simple energy balance model in which turbulent heat fluxes are constrained by the thermodynamic limit of maximum power. For a given magnitude of steady-state temperature change, this approach predicts the transient response as well as the steady-state change in surface energy partitioning and the hydrologic cycle. We show that the transient behavior of the simple model as well as the steady state hydrological sensitivities to greenhouse warming and solar geoengineering are comparable to results from simulations using highly complex models. Many of the global-scale hydrological cycle changes can be understood from a surface energy balance perspective, and our thermodynamically-constrained approach provides a physically robust way of estimating global hydrological changes in response to altered radiative forcing.

  14. Ozone changes under solar geoengineering: implications for UV exposure and air quality

    NASA Astrophysics Data System (ADS)

    Nowack, P. J.; Abraham, N. L.; Braesicke, P.; Pyle, J. A.

    2015-11-01

    Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term Solar Radiation Management (SRM). Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere-ocean coupled climate model, we include atmospheric composition feedbacks such as ozone changes under this scenario. Including the composition changes, we find large reductions in surface UV-B irradiance, with implications for vitamin D production, and increases in surface ozone concentrations, both of which could be important for human health. We highlight that both tropospheric and stratospheric ozone changes should be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  15. Modifications of the Quasi-biennial Oscillation by a Geoengineering Perturbation of the Stratospheric Aerosol Layer

    NASA Technical Reports Server (NTRS)

    Aquila, V.; Garfinkel, C. I.; Newman, P. A.; Oman, L. D.; Waugh, D. W.

    2014-01-01

    This paper examines the impact of geoengineering via stratospheric sulfate aerosol on the quasi-biennial oscillation (QBO) using the NASA Goddard Earth Observing System (GEOS-5) Chemistry Climate Model. We performed four 30-year simulations with a continuous injection of sulfur dioxide on the equator at 0 degree longitude. The four simulations differ by the amount of sulfur dioxide injected (5Tg per year and 2.5 Tg per year) and the altitude of the injection (16km-25km and 22km-25km). We find that such an injection dramatically alters the quasi-biennial oscillation, prolonging the phase of easterly shear with respect to the control simulation. In the case of maximum perturbation, i.e. highest stratospheric aerosol burden, the lower tropical stratosphere is locked into a permanent westerly QBO phase. This locked QBO westerly phase is caused by the increased aerosol heating and associated warming in the tropical lower stratosphere.

  16. Effects of stratospheric sulfate aerosol geo-engineering on cirrus clouds

    NASA Astrophysics Data System (ADS)

    Kuebbeler, Miriam; Lohmann, Ulrike; Feichter, Johann

    2012-12-01

    Cooling the Earth through the injection of sulphate into the stratosphere is one of the most discussed geo-engineering (GE) schemes. Stratospheric aerosols can sediment into the troposphere, modify the aerosol composition and thus might impact cirrus clouds. We use a global climate model with a physically based parametrization for cirrus clouds in order to investigate possible microphysical and dynamical effects. We find that enhanced stratospheric aerosol loadings as proposed by several GE approaches will likely lead to a reduced ice crystal nucleation rate and thus optically thinner cirrus clouds. These optically thinner cirrus clouds exert a strong negative cloud forcing in the long-wave which contributes by 60% to the overall net GE forcing. This shows that indirect effects of stratospheric aerosols on cirrus clouds may be important and need to be considered in order to estimate the maximum cooling derived from stratospheric GE.

  17. The impact of geoengineering on vegetation in experiment G1 of the GeoMIP

    NASA Astrophysics Data System (ADS)

    Glienke, Susanne; Irvine, Peter J.; Lawrence, Mark G.

    2015-10-01

    Solar Radiation Management (SRM) has been proposed as a mean to partly counteract global warming. The Geoengineering Model Intercomparison Project (GeoMIP) has simulated the climate consequences of a number of SRM techniques. Thus far, the effects on vegetation have not yet been thoroughly analyzed. Here the vegetation response to the idealized GeoMIP G1 experiment from eight fully coupled Earth system models (ESMs) is analyzed, in which a reduction of the solar constant counterbalances the radiative effects of quadrupled atmospheric CO2 concentrations (abrupt4 × CO2). For most models and regions, changes in net primary productivity (NPP) are dominated by the increase in CO2, via the CO2 fertilization effect. As SRM will reduce temperatures relative to abrupt4 × CO2, in high latitudes this will offset increases in NPP. In low latitudes, this cooling relative to the abrupt4 × CO2 simulation decreases plant respiration while having little effect on gross primary productivity, thus increasing NPP. In Central America and the Mediterranean, generally dry regions which are expected to experience increased water stress with global warming, NPP is highest in the G1 experiment for all models due to the easing of water limitations from increased water use efficiency at high-CO2 concentrations and the reduced evaporative demand in a geoengineered climate. The largest differences in the vegetation response are between models with and without a nitrogen cycle, with a much smaller CO2 fertilization effect for the former. These results suggest that until key vegetation processes are integrated into ESM predictions, the vegetation response to SRM will remain highly uncertain.

  18. Lifting options for stratospheric aerosol geoengineering: advantages of tethered balloon systems.

    PubMed

    Davidson, Peter; Burgoyne, Chris; Hunt, Hugh; Causier, Matt

    2012-09-13

    The Royal Society report 'Geoengineering the Climate' identified solar radiation management using albedo-enhancing aerosols injected into the stratosphere as the most affordable and effective option for geoengineering, but did not consider in any detail the options for delivery. This paper provides outline engineering analyses of the options, both for batch-delivery processes, following up on previous work for artillery shells, missiles, aircraft and free-flying balloons, as well as a more lengthy analysis of continuous-delivery systems that require a pipe connected to the ground and supported at a height of 20 km, either by a tower or by a tethered balloon. Towers are shown not to be practical, but a tethered balloon delivery system, with high-pressure pumping, appears to have much lower operating and capital costs than all other delivery options. Instead of transporting sulphuric acid mist precursors, such a system could also be used to transport slurries of high refractive index particles such as coated titanium dioxide. The use of such particles would allow useful experiments on opacity, coagulation and atmospheric chemistry at modest rates so as not to perturb regional or global climatic conditions, thus reducing scale-up risks. Criteria for particle choice are discussed, including the need to minimize or prevent ozone destruction. The paper estimates the time scales and relatively modest costs required if a tethered balloon system were to be introduced in a measured way with testing and development work proceeding over three decades, rather than in an emergency. The manufacture of a tether capable of sustaining the high tensions and internal pressures needed, as well as strong winds, is a significant challenge, as is the development of the necessary pumping and dispersion technologies. The greatest challenge may be the manufacture and launch of very large balloons, but means have been identified to significantly reduce the size of such balloons or aerostats

  19. A Multi-Model Examination of Climate Extremes in an Idealized Geoengineering Experiment

    NASA Astrophysics Data System (ADS)

    Curry, C.; Sillmann, J.; Bronaugh, D.

    2013-12-01

    Temperature and precipitation extremes in an idealized climate engineering experiment are examined as part of the Geoengineering Model Intercomparison Project (GeoMIP). In GeoMIP experiment G1, an instantaneous quadrupling of CO2 from its preindustrial control value is offset by a reduction in solar irradiance. Significant changes in the probability density functions of anomalies of monthly surface temperature T and precipitation P were found between G1 and control simulations, featuring an extension of the high-T tail over land, of the low-T tail over ocean, and a shift of P to drier conditions. Using daily model output, we analyzed the frequency of extreme events, such as the coldest night (TNn), warmest day (TXx), and maximum 5-day precipitation amount, and duration indicators such as cold and warm spells and consecutive dry days. The strong heating of the northern high latitudes simulated under CO2 quadrupling is much alleviated under G1, but a significant warming remains, particularly for TNn compared to TXx. Rapid responses tied to land-atmosphere surface energy balance and biogeochemical processes lead to regional increases in absorbed solar radiation at the surface, preferentially increasing monthly mean and maximum daily temperatures over Northern Hemisphere land in summer. Conversely, a cooling of the tropical oceans is reflected in both TNn and TXx, causing a marked increase in cold spell duration. Globally, G1 is more effective in reducing changes in temperature extremes compared to precipitation extremes. Compared to changes in mean values under G1, precipitation extremes are reduced more effectively than means; however, the opposite is true of temperature extremes. The results of our study underline that despite the by-design global efficacy of geoengineering, significant regional disparities in climate change persist, particularly with respect to climate extremes

  20. Antarctic Pumpdown---a New Geoengineering Concept for Capturing and Storing Atmospheric Carbon Dioxide

    NASA Astrophysics Data System (ADS)

    Beget, J. E.

    2014-12-01

    Growing concentrations of carbon dioxide in the atmosphere are increasing global temperatures. This is projected to impact human society in negative ways. Multiple geoengineering approaches have been suggested that might counteract problems created by greenhouse warming, but geoengineering itself can be problematic as some proposed methods would pose environmental risks to the oceans, atmosphere, and biosphere. I propose a new approach that would remove CO2 from the atmosphere and store it in the cryosphere. Carbon dioxide would be captured by seeding the atmosphere over a designated small region of central Antarctica with monoethanolamine (MEA), a well known compound commonly used for CO2 capture in submarines and industrial processes. Monoethanolamine captures and retains carbon dioxide until it encounters water. Because MEA crystals are stable when dry, they would fall from the atmosphere just in the local area where the seeding is done, and they would be naturally buried by snowfalls and preserved in the upper parts of the East Antarctic Ice Sheet, where thawing does not occur. The carbon dioxide removed from the atmosphere by this process could reside safely in this geologic reservoir for thousands of years, based on known flow characteristic of the ice sheet. Also, carbon dioxide stored in this way could be recovered in the future by drilling into the ice sheet to the frozen storage zone. The CO2 Antarctic Pumpdown (CAP) concept could potentially be used to stabilize or reduce the amount of carbon dioxide in the atmosphere, and then to store the carbon dioxide safely and inexpensively in a stable geologic reservoir

  1. ECOSYSTEM IMPACTS OF GEOENGINEERING: A Review for Developing a Science Plan

    SciTech Connect

    Russell, Lynn M; Jackson, Robert B; Norby, Richard J

    2012-01-01

    Geoengineering methods are intended to reduce the magnitude of climate change, which is already having demonstrable effects on ecosystem structure and functioning. Two different types of activities have been proposed: solar radiation management (SRM), or sunlight reflection methods, which involves reflecting a small percentage of solar light back into space to offset the warming due to greenhouse gases, and carbon dioxide removal (CDR), which includes a range of engineered and biological processes to remove carbon dioxide (CO2) from the atmosphere. This report evaluates some of the possible impacts of CDR and SRM on the physical climate and their subsequent influence on ecosystems, which include the risks and uncertainties associated with new kinds of purposeful perturbations to the Earth. Therefore, the question considered in this review is whether CDR and SRM methods would exacerbate or alleviate the deleterious impacts on ecosystems associated with climate changes that might occur in the foreseeable future.Geoengineering methods are intended to reduce the magnitude of climate change, which is already having demonstrable effects on ecosystem structure and functioning. Two different types of activities have been proposed: solar radiation management (SRM), or sunlight reflection methods, which involves reflecting a small percentage of solar light back into space to offset the warming due to greenhouse gases, and carbon dioxide removal (CDR), which includes a range of engineered and biological processes to remove carbon dioxide (CO2) from the atmosphere. This report evaluates some of the possible impacts of CDR and SRM on the physical climate and their subsequent influence on ecosystems, which include the risks and uncertainties associated with new kinds of purposeful perturbations to the Earth. Therefore, the question considered in this review is whether CDR and SRM methods would exacerbate or alleviate the deleterious impacts on ecosystems associated with climate

  2. Black Women in Film Symposium

    ERIC Educational Resources Information Center

    Smith, Barbara

    1974-01-01

    Describes a symposium sponsored in April of last year by the Afro-American and American Studies Departments at Boston University on "Black Image in Films, Stereotyping and Self-Perception"; participants included Susan Batson, Cynthia Belgrave, Ruby Dee, Beah Richards, and Cicely Tyson. (Author/JM)

  3. Technological Change and HRD. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on technological change and human resource development. "New Technologies, Cognitive Demands, and the Implications for Learning Theory" (Richard J. Torraco) identifies four specific characteristics of the tasks involved in using new technologies (contingent versus deterministic tasks, distancing…

  4. Eleventh European Cosmic Ray Symposium

    NASA Astrophysics Data System (ADS)

    1988-08-01

    The biannual Symposium includes all aspects of cosmic ray research. The scientific program was organized under three main headings: cosmic rays in the heliosphere, cosmic rays in the interstellar and extragalactic space, and properties of high-energy interactions as studied by cosmic rays. Selected short communications out of 114 contributed papers were indexed separately for the INIS database.

  5. Diversity in the Workplace. Symposium.

    ERIC Educational Resources Information Center

    2002

    Three papers comprise this symposium on diversity in the workplace. "Factors That Assist and Barriers That Hinder the Success of Diversity Initiatives in Multinational Corporations" (Rose Mary Wentling) reports that factors that assisted in the success were classified under diversity department, human, and work environment; barriers were those of…

  6. 1999 Shuttle Small Payloads Symposium

    NASA Technical Reports Server (NTRS)

    Daelemans, Gerard (Editor); Mosier, Frances L. (Editor)

    1999-01-01

    The 1999 Shuttle Small Payloads Symposium is a combined symposia of the Get Away Special (GAS), Space Experiment Module (SEM), and Hitchhiker programs, and is proposed to continue as an annual conference. The focus of this conference is to educate potential Space Shuttle Payload Bay users as to the types of carrier systems provided and for current users to share experiment concepts.

  7. Learning on the Job. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains two papers from a symposium on learning on the job. "Professional Crisis Workers: Impact of Repeated Exposure to Human Pain and Destructiveness" (Lynn Atkinson-Tovar) examines the following topics: (1) the secondary and vicarious traumatic stress disorder that affects many professional crisis workers who are repeatedly…

  8. Symposium on Dental Health Behavior.

    ERIC Educational Resources Information Center

    Green, Lawrence W., Ed.; And Others

    1974-01-01

    This document presents papers, critiques, and comments from a symposium which assessed the current status of preventive dental behavior. The field was divided into the following three major areas: (a) mass media programs, (b) school health programs, and (c) effect of the private practitioner. Each author was asked to review the literature, provide…

  9. Learning and Job Satisfaction. Symposium.

    ERIC Educational Resources Information Center

    2002

    This symposium is comprised of three papers on learning and job satisfaction. "The Relationship Between Workplace Learning and Job Satisfaction in United States Small to Mid-Sized Businesses" (Robert W. Rowden) reports findings that revealed sufficient evidence to conclude that learning is pervasive in the small to mid-sized businesses studied;…

  10. Learning at the Top. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on learning at the top that was conducted as part of a conference on human resource development (HRD). "Learning at the Top: An Investigation of Nonprofit CEOs' (Chief Executive Officers') Learning Experiences" (John J. Sherlock) reports on a study that used Mezirow's theory of adult learning as…

  11. SYMPOSIUM ON PLANT PROTEIN PHOSPHORYLATION

    SciTech Connect

    JOHN C WALKER

    2011-11-01

    Protein phosphorylation and dephosphorylation play key roles in many aspects of plant biology, including control of cell division, pathways of carbon and nitrogen metabolism, pattern formation, hormonal responses, and abiotic and biotic responses to environmental signals. A Symposium on Plant Protein Phosphorylation was hosted on the Columbia campus of the University of Missouri from May 26-28, 2010. The symposium provided an interdisciplinary venue at which scholars studying protein modification, as it relates to a broad range of biological questions and using a variety of plant species, presented their research. It also provided a forum where current international challenges in studies related to protein phosphorylation could be examined. The symposium also stimulated research collaborations through interactions and networking among those in the research community and engaged students and early career investigators in studying issues in plant biology from an interdisciplinary perspective. The proposed symposium, which drew 165 researchers from 13 countries and 21 States, facilitated a rapid dissemination of acquired knowledge and technical expertise regarding protein phosphorylation in plants to a broad range of plant biologists worldwide.

  12. Symposium: What Is College English?

    ERIC Educational Resources Information Center

    Bloom, Lynn Z.; White, Edward M.; Enoch, Jessica; Hawk, Byron

    2013-01-01

    This symposium explores the role(s) College English has (or has not) had in the scholarly work of four scholars. Lynn Bloom explores the many ways College English influenced her work and the work of others throughout their scholarly lives. Edward M. White examines four articles he has published in College English and draws connections between…

  13. Copyright Law Symposium. No. 23.

    ERIC Educational Resources Information Center

    American Society of Composers, Authors and Publishers, New York, NY.

    This book presents the five national prizewinning papers in the twenty-third copyright law symposium conducted by the American Society of Composers, Authors, and Publishers (ASCAP). Titles of the papers are "The USSR Joins the Universal Copyright Convention" (first prize), "Copyright Misuse: Thirty Years Waiting for the Other Shoe" (second prize),…

  14. Women and Career Development. Symposium.

    ERIC Educational Resources Information Center

    2002

    Three papers comprise this symposium on women and career development. "Enhancing the Career Success of Women Faculty: Mentoring as a Human Resource Development (HRD) Initiative in Higher Education" (Sharon K. Gibson) explores mentoring of women faculty, focusing on the key dimensions of roles and functions, outcomes, gender, and formal and…

  15. Cross-Cultural HRD. Symposium.

    ERIC Educational Resources Information Center

    2002

    The first of three papers from this symposium on cross-cultural human resource development (HRD), "Determinants of Supply of Technical Training Opportunities for Human Capital Development in Kenya" (Moses Waithanji Ngware, Fredrick Muyia Nafukho) reports findings from interviews of technical training institute department heads in Kenya who…

  16. Different Ways of Learning. Symposium.

    ERIC Educational Resources Information Center

    2002

    This document contains three papers from a symposium on different ways of learning. "How Engineers Learn in the Face of Organizational Change" (Robert Reardon) reports on a qualitative study during which nine engineers described how they learned to perform their altered roles after a major reorganization. The study findings supported current…

  17. Foreign Language "Think Tank" Symposium.

    ERIC Educational Resources Information Center

    Thomas, Kathleen H.

    At the Foreign Language"Think Tank" Symposium of April 1975, the following major problems of community college foreign language teachers were identified: (1) low enrollment; (2) attrition; (3) low achievers; (4) articulation with universities; and (5) lack of interest. Suggested solutions included: (Problem 1) advertisement, a foreign language…

  18. Deliberative Mapping of options for tackling climate change: Citizens and specialists ‘open up’ appraisal of geoengineering

    PubMed Central

    Bellamy, Rob; Chilvers, Jason; Vaughan, Naomi E.

    2014-01-01

    Appraisals of deliberate, large-scale interventions in the earth’s climate system, known collectively as ‘geoengineering’, have largely taken the form of narrowly framed and exclusive expert analyses that prematurely ‘close down’ upon particular proposals. Here, we present the findings from the first ‘upstream’ appraisal of geoengineering to deliberately ‘open up’ to a broader diversity of framings, knowledges and future pathways. We report on the citizen strand of an innovative analytic–deliberative participatory appraisal process called Deliberative Mapping. A select but diverse group of sociodemographically representative citizens from Norfolk (United Kingdom) were engaged in a deliberative multi-criteria appraisal of geoengineering proposals relative to other options for tackling climate change, in parallel to symmetrical appraisals by diverse experts and stakeholders. Despite seeking to map divergent perspectives, a remarkably consistent view of option performance emerged across both the citizens’ and the specialists’ deliberations, where geoengineering proposals were outperformed by mitigation alternatives. PMID:25224904

  19. Identifying the changes of geo-engineering properties of dunites due to weathering utilizing electrical resistivity tomography (ERT)

    NASA Astrophysics Data System (ADS)

    Ündül, Ömer; Tuğrul, Atiye; Özyalın, Şenol; Halil Zarif, İ.

    2015-04-01

    Weathering phenomena have an important role in many construction facilities with varying depths and grades. Due to the anisotropic and heterogeneous nature of weathering profiles of some rocks, uncertainities exist in determining the geo-engineering properties. Geo-electrical studies have been utilized to overcome such uncertainities for various subsurface conditions including the determination of boundaries between weathered and unweathered parts of different rock types. In this study, the electrical resistivity tomography (ERT) results were correlated with conventional methods in determining the effects of weathering on the geo-engineering properties of dunites. During the research, weathering grades were determined by field studies including discontinuity spacings, aperture and properties of fill materials. The detailed petrographical studies, determination of petrophysical properties (e.g. water absorption and effective porosity) and mechanical properties (e.g. unconfined compressive strength (UCS)) constitute the laboratory studies. ERT studies were carried out in a row of sixty electrodes with electrode spacings of 0.5 m utilizing a Wenner-Schlumberger configuration. According to the comparison of the inversion model sections with the weathering profiles obtained by field and laboratory studies it is concluded that the use of ERT with a Wenner-Schlumberger configuration supplies comparable data for wider subsurface areas from the view of weathering and its effect on geo-engineering properties of dunites. In addition, ERT techniques are very useful where conventional techniques are inadequate in determining the full weathering profile.

  20. Impact of Very Short-lived Halogens on Stratospheric Ozone Abundance and UV radiation in a Geo-engineered Atmosphere

    NASA Astrophysics Data System (ADS)

    Tilmes, S.; Kinnison, D. E.; Garcia, R. R.; Salawitch, R. J.; Canty, T. P.; Lee-Taylor, J.; Madronich, S.; Chance, K.

    2012-12-01

    The impact of BrO from very short-lived (VSL) source species on stratospheric ozone is investigated for a hypothetical geo-engineered atmosphere in 2040, assuming the injection of sulfuric acid aerosols. An estimated amount of stratospheric halogens from VSL sources based on satellite observations, model results and previous studies, result in lower column ozone for nearly all seasons and nearly all latitudes, and up to 4% in summer mid- and high latitudes. Considering an upper limit of VSL sources, the annual increase in surface erythemal UV radiation (UV_ERY) due to the decrease in ozone as a result of geo-engineering is 12% and 6% in southern and northern high latitudes, respectively. The increase of UV_ERY due to a reduction of ozone for low and mid latitudes is balanced by the reduction of UV_ERY due to aerosol scattering, if VSL halogen sources are not considered. However, VSL halogens results in additional ozone depletion and in an increase of UV_ERY of up to 5% in spring and fall in mid- and high latitudes as a result of geo-engineering. This study demonstrates that VSL halogens should be considered in models that assess the impact of stratospheric sulfur injections on the ozone layer.

  1. Report on the 2009 ESO Fellows Symposium

    NASA Astrophysics Data System (ADS)

    Emsellem, Eric; West, Michael; Leibundgut, Bruno

    2009-09-01

    The fourth ESO Fellows Symposium took place in Garching from 8-10 June 2009. This year's symposium brought together 28 ESO Fellows from Chile and Germany to meet their colleagues from across the ocean, discuss their research and provide feedback on ESO's Fellowship programme. This year's symposium also included training workshops to enhance the practical skills of ESO Fellows in today's competitive job market.

  2. XXth Hadron Collider Physics Symposium

    NASA Astrophysics Data System (ADS)

    In 2009, the Hadron Collider Physics Symposium took place in Evian (France), on the shore of the Geneva Lake, from 16-20 November. It was jointly organised by CERN and the French HEP community (CNRS-IN2P3 and CEA-IRFU). This year's symposium come at an important time for both the Tevatron and LHC communities. It stimulated the completion of analyses for a significant Tevatron data sample, and it allowed an in-depth review of the readiness of the LHC and its detectors just before first collisions. The programme includes sessions on top-quark and electro-weak physics, QCD, B physics, new phenomena, electro-weak symmetry breaking, heavy ions, and the status and commissioning of the LHC machine and its experiments. Conference website : http://hcp2009.in2p3.fr/

  3. The 1975 Ride Quality Symposium

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A compilation is presented of papers reported at the 1975 Ride Quality Symposium held in Williamsburg, Virginia, August 11-12, 1975. The symposium, jointly sponsored by NASA and the United States Department of Transportation, was held to provide a forum for determining the current state of the art relative to the technology base of ride quality information applicable to current and proposed transportation systems. Emphasis focused on passenger reactions to ride environment and on implications of these reactions to the design and operation of air, land, and water transportation systems acceptable to the traveling public. Papers are grouped in the following five categories: needs and uses for ride quality technology, vehicle environments and dynamics, investigative approaches and testing procedures, experimental ride quality studies, and ride quality modeling and criteria.

  4. 38th Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Boesiger, Edward A. (Compiler)

    2006-01-01

    The Aerospace Mechanisms Symposium (AMS) provides a unique forum for those active in the design, production and use of aerospace mechanisms. A major focus is the reporting of problems and solutions associated with the development and flight certification of new mechanisms. Organized by the Mechanisms Education Association, the National Aeronautics and Space Administration and Lockheed Martin Space Systems Company (LMSSC) share the responsibility for hosting the AMS. Now in its 38th symposium, the AMS continues to be well attended, attracting participants from both the U.S. and abroad. The 38th AMs, hosted by the NASA Langley Research Center in Williamsburg, Virginia, was held May 17-19, 2006. During these three days, 34 papers were presented. Topics included gimbals, tribology, actuators, aircraft mechanisms, deployment mechanisms, release mechanisms, and test equipment. Hardware displays during the supplier exhibit gave attendees an opportunity to meet with developers of current and future mechanism components.

  5. 37th Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Boesiger, Edward A. (Compiler)

    2004-01-01

    The Aerospace Mechanisms Symposium (AMS) provides a unique forum for those active in the design, production and use of aerospace mechanisms. A major focus is reporting problems and solutions associated with the development and flight certification of new mechanisms. Organized by the Mechanisms Education Association, NASA and Lockheed Martin Space Systems Company (LMSSC) share the responsibility for hosting the AMS. Now in its 37th symposium, the AMS continues to be well attended, attracting participants from both the U.S. and abroad. The 37th AMS, hosted by the Johnson Space Center (JSC) in Galveston, Texas, was held May 19, 20 and 21, 2004. During these three days, 34 papers were presented. Topics included deployment mechanisms, tribology, actuators, pointing and optical mechanisms, Space Station and Mars Rover mechanisms, release mechanisms, and test equipment. Hardware displays during the supplier exhibit gave attendees an opportunity to meet with developers of current and future mechanism components.

  6. 39th Aerospace Mechanisms Symposium

    NASA Technical Reports Server (NTRS)

    Boesiger, E. A. (Compiler)

    2008-01-01

    The Aerospace Mechanisms Symposium (AMS) provides a unique forum for those active in the design, production, and use of aerospace mechanisms. A major focus is the reporting of problems and solutions associated with the development and flight certification of new mechanisms. Organized by the Mechanisms Education Association, NASA Marshall Space Flight Center (MSFC) and Lockheed Martin Space Systems Company (LMSSC) share the responsibility for hosting the AMS. Now in its 39th symposium, the AMS continues to be well attended, attracting participants from both the United States and abroad. The 39th AMS was held in Huntsville, Alabama, May 7-9, 2008. During these 3 days, 34 papers were presented. Topics included gimbals and positioning mechanisms, tribology, actuators, deployment mechanisms, release mechanisms, and sensors. Hardware displays during the supplier exhibit gave attendees an opportunity to meet with developers of current and future mechanism components.

  7. Ninth international symposium on radiopharmacology

    SciTech Connect

    1995-12-31

    The goal of this Symposium is to provide a forum for those international scientists involved in applying the principles of pharmacology and radiation biology to the development of agents for the diagnosis and treatment of disease. The program will highlight state-of-the-art progress in the development of those agents used in conjunction with some form of radiation such as radiopharmaceuticals, radiopaques, photo- and radiosensitizing drugs, and neutron capture agents. An underlying pharmacokinetic parameter associated with all these agents is the need for site-specific delivery to an organ or tumor. Therefore, a major goal of the symposium will be to address those pharmacologic principles for targeting molecules to specific tissue sites. Accordingly, session themes will include receptor-mediated processes, membrane transporters, antibody interactions, metabolic trapping, and oligonucleotide-antisense mechanisms.

  8. Simulation of how a geo-engineering intervention to restore arctic sea ice might work in practice

    NASA Astrophysics Data System (ADS)

    Forster, Piers; Jackson, Lawrence

    2014-05-01

    The declining trend in annual minimum Arctic sea ice coverage and years of more pronounced drops like 2007 and 2012 raise the prospect of an Arctic Ocean largely free of sea ice in late summer and the potential for a climate crisis or emergency. In a novel computer simulation, we treated one realisation of a climate model (HadGEM2) as the real world and tried to restore its Arctic sea ice by the rapid deployment of geo-engineering with emission of SO2 into the Arctic stratosphere. The objective was to restore the annual minimum Arctic sea ice coverage to levels seen in the late twentieth century using as little geo-engineering as possible. We took intervention decisions as one might do in the real world: by committee, using a limited set of uncertain "observations" from our simulated world and using models and control theory to plan the best intervention strategy for the coming year - so learning as we went and being thrown off course by future volcanoes and technological breakdowns. Uncertainties in real world observations were simulated by applying noise to emerging results from the climate model. Volcanic radiative forcing of twenty-first century climate was included with the timing and magnitude of the simulated eruptions unknown by the "geo-engineers" until after the year of the eruption. Monitoring of Arctic sea ice with the option to intervene with SO2 emissions started from 2018 and continued to 2075. Simulated SO2 emissions were made in January-May each year at a latitude of 79o N and an altitude within the range of contemporary tanker aircraft. The magnitude of emissions was chosen annually using a model predictive control process calibrated using results from CMIP5 models (excluding HadGEM2), using the simplified climate model MAGICC and assimilation of emerging annual results from the HadGEM2 "real world". We found that doubts in the minds of the "geo-engineers" of the radiative effect of their interventions, the side effects of their past interventions

  9. Phased arrays 1985 symposium: Proceedings

    NASA Astrophysics Data System (ADS)

    Steyskal, H. P.

    1985-08-01

    The Phased Arrays '85 Symposium, sponsored by the Rome Air Development Center, the MITRE Corporation, and the University of Massachusetts, was held at the MITRE Corporation 15 to 18 October and reviewed the state-of-the-art of phased array antenna systems and of the technology for next generation systems. This report contains the full papers which were presented with clearance for unlimited distribution.

  10. FIRST BH COCHRANE SYMPOSIUM HELD

    PubMed Central

    Mahmic-Kaknjo, Mersiha; Novo, Ahmed; Krleza-Jeric, Karmela

    2016-01-01

    The first BH Cochrane Symposium was held on 12 October 2015 in Sarajevo, Bosnia and Herzegovina (BH), organized by the Agency for Quality and Accreditation in Healthcare in Federation of BH (AKAZ) and Medical Faculty University of Sarajevo. A group of ten national and international experts presented the Cochrane organization and systematic reviews, as well as the IMPACT Observatory, development of guidelines in BH, and the role of AKAZ. Examples of the development and use of Cochrane reviews in evidence informed decision making in health as well as research integrity were presented and discussed. Major BH decision makers and interested professionals from all over BH participated in a symposium and its lively discussion, especially from the perspective of Cochrane and its activities in BH, and the collaboration with the Croatian Cochrane. It can be expected that this symposium will inspire further growth of participation and use of Cochrane in BH and increase the awareness of various aspects of evidence informed medicine and research integrity. PMID:27047274