Emissions pathways, climate change, and impacts on California

Science.gov (United States)

Hayhoe, Katharine; Cayan, Daniel; Field, Christopher B.; Frumhoff, Peter C.; Maurer, Edwin P.; Miller, Norman L.; Moser, Susanne C.; Schneider, Stephen H.; Cahill, Kimberly Nicholas; Cleland, Elsa E.; Dale, Larry; Drapek, Ray; Hanemann, R. Michael; Kalkstein, Laurence S.; Lenihan, James; Lunch, Claire K.; Neilson, Ronald P.; Sheridan, Scott C.; Verville, Julia H.

2004-01-01

The magnitude of future climate change depends substantially on the greenhouse gas emission pathways we choose. Here we explore the implications of the highest and lowest Intergovernmental Panel on Climate Change emissions pathways for climate change and associated impacts in California. Based on climate projections from two state-of-the-art climate models with low and medium sensitivity (Parallel Climate Model and Hadley Centre Climate Model, version 3, respectively), we find that annual temperature increases nearly double from the lower B1 to the higher A1fi emissions scenario before 2100. Three of four simulations also show greater increases in summer temperatures as compared with winter. Extreme heat and the associated impacts on a range of temperature-sensitive sectors are substantially greater under the higher emissions scenario, with some interscenario differences apparent before midcentury. By the end of the century under the B1 scenario, heatwaves and extreme heat in Los Angeles quadruple in frequency while heat-related mortality increases two to three times; alpine/subalpine forests are reduced by 50–75%; and Sierra snowpack is reduced 30–70%. Under A1fi, heatwaves in Los Angeles are six to eight times more frequent, with heat-related excess mortality increasing five to seven times; alpine/subalpine forests are reduced by 75–90%; and snowpack declines 73–90%, with cascading impacts on runoff and streamflow that, combined with projected modest declines in winter precipitation, could fundamentally disrupt California's water rights system. Although interscenario differences in climate impacts and costs of adaptation emerge mainly in the second half of the century, they are strongly dependent on emissions from preceding decades. PMID:15314227

Economic implications of climate-driven trends in global hydropower generation

Science.gov (United States)

Turner, S. W. D.; Galelli, S.; Hejazi, M. I.; Clarke, L.; Edmonds, J.; Kim, S. H.

2017-12-01

Recent progress in global scale hydrological and dam modeling has allowed for the study of climate change impacts on global hydropower production. Here we explore how these impacts could affect the composition of global electricity supply, and what those changes could mean for power sector emissions and investment needs in the 21st century. Regional hydropower projections are developed for two emissions scenarios by forcing a coupled global hydrological and dam model (1593 major hydropower dams; 54% global installed capacity) with downscaled, bias-corrected climate realizations derived from sixteen General Circulation Models (GCMs). To incorporate possible non-linearity in hydropower response to climate change, dam simulations incorporate plant specifications (e.g., maximum turbine flow), reservoir storage dynamics, reservoir bathymetry, evaporation losses and bespoke, site specific operations. Consequent impacts on regional and global-level electricity generation and associated emissions and investment costs are examined using the Global Change Assessment Model (GCAM). We show that changes in hydropower generation resulting from climate change can shift power demands onto and away from carbon intensive technologies, resulting in significant impacts on CO2 emissions for several regions. Many of these countries are also highly vulnerable to investment impacts (costs of new electricity generating facilities to make up for shortfalls in hydro), which in some cases amount to tens of billions of dollars by 2100. The Balkans region—typified by weak economies in a drying region that relies heavily on hydropower—emerges as the most vulnerable. Reduced impacts of climate change on hydropower production under a low emissions scenario coincide with increased costs of marginal power generating capacity (low emissions requires greater uptake of clean generating technologies, which are more expensive). This means impacts on power sector investment costs are similar for high

Climate scenarios for California

Science.gov (United States)

Cayan, Daniel R.; Maurer, Ed; Dettinger, Mike; Tyree, Mary; Hayhoe, Katharine; Bonfils, Celine; Duffy, Phil; Santer, Ben

2006-01-01

Possible future climate changes in California are investigated from a varied set of climate change model simulations. These simulations, conducted by three state-of-the-art global climate models, provide trajectories from three greenhouse gas (GHG) emission scenarios. These scenarios and the resulting climate simulations are not “predictions,” but rather are a limited sample from among the many plausible pathways that may affect California’s climate. Future GHG concentrations are uncertain because they depend on future social, political, and technological pathways, and thus the IPCC has produced four “families” of emission scenarios. To explore some of these uncertainties, emissions scenarios A2 (a medium-high emissions) and B1 (low emissions) were selected from the current IPCC Fourth climate assessment, which provides several recent model simulations driven by A2 and B1 emissions. The global climate model simulations addressed here were from PCM1, the Parallel Climate Model from the National Center for Atmospheric Research (NCAR) and U.S. Department of Energy (DOE) group, and CM2.1 from the National Oceanic and Atmospheric Administration (NOAA) Geophysical Fluids Dynamics Laboratory (GFDL).

Reducing Methane Emissions: The Other Climate Change Challenge

International Nuclear Information System (INIS)

Dessus, Benjamin; Laponche, Bernard

2008-08-01

Climate change studies show that it is vital to massively reduce atmospheric concentrations of greenhouse gases in the coming decades in order to limit the global average temperature rise ultimately to 2 or 3 deg. C and to prevent the occurrence of irreversible phenomena such as the melting of permafrost. To achieve these targets, climate experts construct scenarios estimating the changes in atmospheric concentrations of the different greenhouse gases, and determine the maximum levels that these concentrations should reach. Climate change policy targets are then set in terms of greenhouse gas emission reductions. In order to simplify the global assessment of the impact of emissions of these different greenhouse gases on global warming, the international community has adopted rules of equivalence to make it possible to take into account the emissions of non-CO_2 greenhouse gases within one single unit: the ton of CO_2 equivalent (t CO_2 eq). This is achieved by using the 'Global Warming Potential' (GWP) indicator which indicates the ratio of the respective climate impacts of a pulse emission of the greenhouse gas considered over a given period of time to a pulse emission of CO_2 of the same volume in the same year. A reference period of 100 years was defined and this means therefore that in terms of climate impacts, the emission of 1 ton of CH_4 is 'worth' the emission of 21 tons of CO_2. The study presented in this document shows that the widespread use of this equivalence to calculate not only past emissions, but also future emissions anticipated or emissions avoided over a period in the past or in the future, has led to the climate impact of CH_4 emissions being underestimated. This is because the GWP of CH_4 varies considerably depending on the period under consideration. This underestimation is accentuated even more if the respective impacts of avoided emissions of CO_2 and CH_4 are compared, either on a permanent basis or over a limited period of time. Thus

Emissions trading for climate policy - US and European perspectives

Energy Technology Data Exchange (ETDEWEB)

Bernd Hansjuergens (ed.) [Martin Luther-Universitaet Halle-Wittenburg (Germany)

2005-07-01

The 1997 Kyoto Conference introduced emissions trading as a new policy instrument for climate protection. Bringing together scholars in the fields of economics, political science and law, this book provides a description, analysis and evaluation of different aspects of emissions trading as an instrument to control greenhouse gases. The authors analyse theoretical aspects of regulatory instruments for climate policy, provide an overview of US experience with market-based instruments, draw lessons from existing trading schemes for the control of greenhouse gases, and discuss options for emissions trading in climate policy. They also highlight the background of climate policy and instrument choice in the US and Europe and of the emerging new systems in Europe, particularly the new EU's directive for a CO{sub 2} emissions trading system. 8 figs., 15 tabs.

A decade of sea level rise slowed by climate-driven hydrology.

Science.gov (United States)

Reager, J T; Gardner, A S; Famiglietti, J S; Wiese, D N; Eicker, A; Lo, M-H

2016-02-12

Climate-driven changes in land water storage and their contributions to sea level rise have been absent from Intergovernmental Panel on Climate Change sea level budgets owing to observational challenges. Recent advances in satellite measurement of time-variable gravity combined with reconciled global glacier loss estimates enable a disaggregation of continental land mass changes and a quantification of this term. We found that between 2002 and 2014, climate variability resulted in an additional 3200 ± 900 gigatons of water being stored on land. This gain partially offset water losses from ice sheets, glaciers, and groundwater pumping, slowing the rate of sea level rise by 0.71 ± 0.20 millimeters per year. These findings highlight the importance of climate-driven changes in hydrology when assigning attribution to decadal changes in sea level. Copyright © 2016, American Association for the Advancement of Science.

Comparing climate policies to reduce carbon emissions in China

International Nuclear Information System (INIS)

Li, Aijun; Lin, Boqiang

2013-01-01

Currently, China is the largest carbon emitter mainly due to growing consumption of fossil fuels. In 2009, the Chinese government committed itself to reducing domestic carbon emissions per unit of GDP by 40–45% by 2020 compared to 2005 levels. Therefore, it is a top priority for the Chinese government to adopt efficient policy instruments to reduce its carbon intensity. Against this background, this paper develops a general equilibrium model and seeks to provide empirical contributions by comparing the potential impacts of several different policy options to reduce China's carbon emissions. The main findings are as follows. Firstly, these climate policies would affect the structure of economy and contribute to carbon emissions reduction and carbon intensity reduction. Secondly, there would be significant differences in the economic and environmental effects among different climate policies and hence, the government would trade-off among different economic objectives to overcome any potential resistances. Thirdly, there would be considerable differences in the emissions effects of absolute and intensity-based carbon emissions controls, implying that the government might adopt different climate policies for absolute or intensity-based carbon emissions controls. Looking ahead, the government should trade-off among different objectives when designing climate reforms. - Highlights: • We develop a static general equilibrium model to simulate the impacts of climate policies. • We compare the potential impacts of various climate policies in China. • We discuss how to design these policies to make them more effective

U.S. ozone air quality under changing climate and anthropogenic emissions.

Science.gov (United States)

Racherla, Pavan N; Adams, Peter J

2009-02-01

We examined future ozone (O3) air quality in the United States (U.S.) under changing climate and anthropogenic emissions worldwide by performing global climate-chemistry simulations, utilizing various combinations of present (1990s) and future (Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A2 2050s) climates, and present and future (2050s; IPCC SRES A2 and B1) anthropogenic emissions. The A2 climate scenario is employed here because it lies at the upper extreme of projected climate change for the 21st century. To examine the sensitivity of U.S. O3 to regional emissions increases (decreases), the IPCC SRES A2 and B1 scenarios, which have overall higher and lower O3-precursor emissions for the U.S., respectively, have been chosen. We find that climate change, by itself, significantly worsens the severity and frequency of high-O3 events ("episodes") over most locations in the U.S., with relatively small changes in average O3 air quality. These high-O3 increases due to climate change alone will erode moderately the gains made under a U.S. emissions reduction scenario (e.g., B1). The effect of climate change on high- and average-O3 increases with anthropogenic emissions. Insofar as average O3 air quality is concerned, changes in U.S. anthropogenic emissions will play the most important role in attaining (or not) near-term U.S. O3 air quality standards. However, policy makers must plan appropriately for O3 background increases due to projected increases in global CH4 abundance and non-U.S. anthropogenic emissions, as well as potential local enhancements that they could cause. These findings provide strong incentives for more-than-planned emissions reductions at locations that are currently O3-nonattainment.

Climate/chemistry feedbacks and biogenic emissions.

Science.gov (United States)

Pyle, John A; Warwick, Nicola; Yang, Xin; Young, Paul J; Zeng, Guang

2007-07-15

The oxidizing capacity of the atmosphere is affected by anthropogenic emissions and is projected to change in the future. Model calculations indicate that the change in surface ozone at some locations could be large and have significant implications for human health. The calculations depend on the precise scenarios used for the anthropogenic emissions and on the details of the feedback processes included in the model. One important factor is how natural biogenic emissions will change in the future. We carry out a sensitivity calculation to address the possible increase in isoprene emissions consequent on increased surface temperature in a future climate. The changes in ozone are significant but depend crucially on the background chemical regime. In these calculations, we find that increased isoprene will increase ozone in the Northern Hemisphere but decrease ozone in the tropics. We also consider the role of bromine compounds in tropospheric chemistry and consider cases where, in a future climate, the impact of bromine could change.

Global Air Quality and Climate

Science.gov (United States)

Fiore, Arlene M.; Naik, Vaishali; Steiner, Allison; Unger, Nadine; Bergmann, Dan; Prather, Michael; Righi, Mattia; Rumbold, Steven T.; Shindell, Drew T.; Skeie, Ragnhild B.;

A forward looking, actor based, indicator for climate gas emissions

Energy Technology Data Exchange (ETDEWEB)

Ericson, Torgeir; Randers, Joergen

2011-04-15

The most commonly used Norwegian indicator for climate change displays historical emissions and compare with Norway's Kyoto target. This indicator says little about future emissions, about the ongoing Norwegian effort to reduce climate gas emissions, or about its effect on sustainability. In this paper we propose an indicator that improves on these weaknesses. We present a forward looking climate indicator that in addition to historic data includes business as usual scenarios, different proposals for future domestic emissions, and national or international commitments and agreements. This indicator presents - in one graph - a broad diversity of views on how the climate challenge should be handled from now and into the future. This indicator-graph may contribute to a more transparent discussion of available policy options. (Author)

Climate-driven changes in water level

DEFF Research Database (Denmark)

Hansen, Rikke Bjerring; Olsen, Jesper; Jeppesen, Erik

2013-01-01

level rose. Moreover, Nymphaeaceae trichosclereids were abundant during the period of algal enrichment. Cladoceran taxa associated with floating leaved plants or benthic habitats responded in a complex way to changes in water level, but the cladoceran assemblages generally reflected deep lake conditions...... hydrology driven by precipitation. The isotopic, sedimentary and plant macrofossil records suggested that the lake level started to decrease around 8400 cal. yr BP, the decrease accelerating during 8350-8260 before an abrupt increase during 8260-8210. This pattern shows that the climate anomaly started...... rates of cladoceran subfossils and algal pigments, possibly due to increased turbidity and reduced nutrient input during this drier period. Pigment analysis also showed added importance of diatoms and cryptophytes during this climate anomaly, while cyanobacteria became more important when the water...

The implications of China’s investment-driven economy on its energy consumption and carbon emissions

International Nuclear Information System (INIS)

Fu, Feng; Ma, Linwei; Li, Zheng; Polenske, Karen R.

2014-01-01

Highlights: • The energy implications of China’s investment-driven (ID) economy are analyzed. • An expenditure-approach-based framework is applied to define the ID energy consumption. • An input–output model is built to identify the volume of China’s ID energy consumption. • Insights are gained for determining the saving potentials of China’s ID energy consumption. - Abstract: In this paper, we aim to fill the research gap by analyzing the relationship between China’s domestic investment and energy consumption, as well as related carbon emissions. First, we use an expenditure-approach-based framework to qualitatively examine the effects of China’s domestic investment on its energy consumption. Based on this framework, we define and differentiate the investment-driven energy consumption and carbon emissions from that which is driven by other economic activities. Second, we establish an allocation model to quantify China’s investment-driven energy consumption and carbon emissions. The results reveal that in 2007, China’s domestic investment contributed one third of both its energy consumption and carbon emissions. Further results show that a majority of this investment-driven energy consumption and carbon emissions, namely nine tenths of the total, is attributable to the construction and manufacturing sectors. Finally, we use the construction sector as a case to discuss how to determine the energy-saving and emission-reduction potential of improving investment-driven energy consumption practices

Agriculture-driven deforestation in the tropics from 1990-2015: emissions, trends and uncertainties

Science.gov (United States)

Carter, Sarah; Herold, Martin; Avitabile, Valerio; de Bruin, Sytze; De Sy, Veronique; Kooistra, Lammert; Rufino, Mariana C.

2018-01-01

Limited data exists on emissions from agriculture-driven deforestation, and available data are typically uncertain. In this paper, we provide comparable estimates of emissions from both all deforestation and agriculture-driven deforestation, with uncertainties for 91 countries across the tropics between 1990 and 2015. Uncertainties associated with input datasets (activity data and emissions factors) were used to combine the datasets, where most certain datasets contribute the most. This method utilizes all the input data, while minimizing the uncertainty of the emissions estimate. The uncertainty of input datasets was influenced by the quality of the data, the sample size (for sample-based datasets), and the extent to which the timeframe of the data matches the period of interest. Area of deforestation, and the agriculture-driver factor (extent to which agriculture drives deforestation), were the most uncertain components of the emissions estimates, thus improvement in the uncertainties related to these estimates will provide the greatest reductions in uncertainties of emissions estimates. Over the period of the study, Latin America had the highest proportion of deforestation driven by agriculture (78%), and Africa had the lowest (62%). Latin America had the highest emissions from agriculture-driven deforestation, and these peaked at 974 ± 148 Mt CO2 yr-1 in 2000-2005. Africa saw a continuous increase in emissions between 1990 and 2015 (from 154 ± 21-412 ± 75 Mt CO2 yr-1), so mitigation initiatives could be prioritized there. Uncertainties for emissions from agriculture-driven deforestation are ± 62.4% (average over 1990-2015), and uncertainties were highest in Asia and lowest in Latin America. Uncertainty information is crucial for transparency when reporting, and gives credibility to related mitigation initiatives. We demonstrate that uncertainty data can also be useful when combining multiple open datasets, so we recommend new data

Climate change: evidence of human causes and arguments for emissions reduction.

Science.gov (United States)

Baum, Seth D; Haqq-Misra, Jacob D; Karmosky, Chris

2012-06-01

In a recent editorial, Raymond Spier expresses skepticism over claims that climate change is driven by human actions and that humanity should act to avoid climate change. This paper responds to this skepticism as part of a broader review of the science and ethics of climate change. While much remains uncertain about the climate, research indicates that observed temperature increases are human-driven. Although opinions vary regarding what should be done, prominent arguments against action are based on dubious factual and ethical positions. Thus, the skepticisms in the recent editorial are unwarranted. This does not diminish the general merits of skeptical intellectual inquiry.

From climate change to emissions trading : a briefing

International Nuclear Information System (INIS)

Marcu, A.

2002-01-01

Global warming is caused by the presence of greenhouse gases (GHGs) in the earth's atmosphere. These gases include, carbon dioxide, nitrous oxides, sulphur dioxide and methane. GHGs trap heat between the earth's atmosphere and the earth's surface to cause an overall warming trend of the Earth. The United Nations Framework Convention on Climate Change was established to address the issue of climate change and to determine the anthropogenic impact on climate change. Evidence from ice cores suggest that global warming has occurred in the past. The current state of global warming was examined by comparing the climate of today with that of the past. It was determined that the current global warming trend surpasses that of any ever observed in the past. The Kyoto Protocol was adopted in 1997 as a policy set to address the need for the world to reduce GHG emissions into the atmosphere. The Kyoto Protocol puts forth 3 sets of mechanisms to help businesses reduce GHG emissions. Emissions trading is one of them: it is a financial flexibility mechanism that allows businesses that have emitted more than their allowed share of GHGs to buy allowances from business that have emitted fewer GHGs than they were allowed. Emissions trading does not create reductions, however, it identifies the most economical solution to reduce GHGs. TransAlta, Ontario Power Generation and Suncor have conducted a few transactions to see how the market will work. There will be a global register to keep track of all assigned allowances. The paper described government action in addressing the climate change issue with reference to actions in the United Kingdom, Netherlands, Denmark and Switzerland. Canada has initiated the Greenhouse Gas Emission Reduction Trading Pilot (GERT) to test the effectiveness of emission reduction trading for GHGs in the Canadian context. GERT is a partnership between the federal government, some provinces, industry, labour and environmental groups. Ontario has established a

Act locally, trade globally. Emissions trading for climate policy

Energy Technology Data Exchange (ETDEWEB)

none

2005-07-01

Climate policy raises a number of challenges for the energy sector, the most significant being the transition from a high to a low-CO2 energy path in a few decades. Emissions trading has become the instrument of choice to help manage the cost of this transition, whether used at international or at domestic level. Act Locally, Trade Globally, offers an overview of existing trading systems, their mechanisms, and looks into the future of the instrument for limiting greenhouse gas emissions. Are current markets likely to be as efficient as the theory predicts? What is, if any, the role of governments in these markets? Can domestic emissions trading systems be broadened to activities other than large stationary energy uses? Can international emissions trading accommodate potentially diverse types of emissions targets and widely different energy realities across countries? Are there hurdles to linking emissions trading systems based on various design features? Can emissions trading carry the entire burden of climate policy, or will other policy instruments remain necessary? In answering these questions, Act Locally, Trade Globally seeks to provide a complete picture of the future role of emissions trading in climate policy and the energy sector.

Climate-change-driven accelerated sea-level rise detected in the altimeter era.

Science.gov (United States)

Nerem, R S; Beckley, B D; Fasullo, J T; Hamlington, B D; Masters, D; Mitchum, G T

2018-02-27

Using a 25-y time series of precision satellite altimeter data from TOPEX/Poseidon, Jason-1, Jason-2, and Jason-3, we estimate the climate-change-driven acceleration of global mean sea level over the last 25 y to be 0.084 ± 0.025 mm/y 2 Coupled with the average climate-change-driven rate of sea level rise over these same 25 y of 2.9 mm/y, simple extrapolation of the quadratic implies global mean sea level could rise 65 ± 12 cm by 2100 compared with 2005, roughly in agreement with the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5) model projections. Copyright © 2018 the Author(s). Published by PNAS.

Emissions trading and the climate change levy

International Nuclear Information System (INIS)

Connett, Richard

2000-01-01

This paper discusses the flexible mechanisms established in the Kyoto Protocol of the UN Framework on Climate Change focussing on the mechanism whereby countries achieving their target for reducing the emissions of greenhouse gases can trade their excess to countries having difficulty achieving their target. UK measures to meet their commitment, the UK government's proposed climate change levy on the use of energy, negotiated agreements, emissions trading, and the nature, supply and trading of permits are examined. Compatibility with international agreements and the Integrated Pollution Prevention and Control (IPPC) Directive, monitoring, and penalties are considered

Climate Impacts From a Removal of Anthropogenic Aerosol Emissions

Science.gov (United States)

Samset, B. H.; Sand, M.; Smith, C. J.; Bauer, S. E.; Forster, P. M.; Fuglestvedt, J. S.; Osprey, S.; Schleussner, C.-F.

2018-01-01

Limiting global warming to 1.5 or 2.0°C requires strong mitigation of anthropogenic greenhouse gas (GHG) emissions. Concurrently, emissions of anthropogenic aerosols will decline, due to coemission with GHG, and measures to improve air quality. However, the combined climate effect of GHG and aerosol emissions over the industrial era is poorly constrained. Here we show the climate impacts from removing present-day anthropogenic aerosol emissions and compare them to the impacts from moderate GHG-dominated global warming. Removing aerosols induces a global mean surface heating of 0.5-1.1°C, and precipitation increase of 2.0-4.6%. Extreme weather indices also increase. We find a higher sensitivity of extreme events to aerosol reductions, per degree of surface warming, in particular over the major aerosol emission regions. Under near-term warming, we find that regional climate change will depend strongly on the balance between aerosol and GHG forcing.

Norwegian Arctic climate. Climate influencing emissions, scenarios and mitigation options at Svalbard

Energy Technology Data Exchange (ETDEWEB)

Vestreng, Vigdis; Kallenborn, Roland; Oekstad, Elin

2010-07-01

The goal of this study was to establish an emission inventory and emission scenarios for climate influencing compounds at Svalbard, as a basis to develop strategies for emission reduction measures and policies. Emissions for the years 2000-2007 have been estimated for the Svalbard Zone. This area, covering about 173 000 km{sub 2}, ranges from 10 E to 35 E longitude and 74 N to 81 N latitude (Figure 1). In addition, air and ship transport between Tromsoe at the Norwegian mainland and Svalbard has been included. Pollutants considered in our inventory are carbon dioxide (CO{sub 2}), methane (CH{sub 4}), Sulphur dioxide (SO{sub 2}), Nitrogen oxides (NO{sub x} as NO{sub 2}), and for the first time also estimates of black carbon (BC, soot) and organic carbon (OC) have been included. Our results show that emissions of all pollutants have increased over the time span 2000-2007 (Figure 2), and are expected to increase also in the future if additional measures are not implemented (Figure 12). The emissions from Svalbard are minuscule compared to emission released from the Norwegian mainland and waters (1% in the case of CO{sub 2}). Even so, local releases of climate influencing compounds in the vulnerable Arctic may turn out to make a difference both with respect to adverse environmental effects and to climate change. Emissions have been estimated for all activities of any significance taking place at and around Svalbard. Combustion sources as well as fugitive emissions of methane are included. The main sectors are coal mining, energy production and transportation. Pollution from 28 sub sectors related to these activities has been estimated. The scope of this work differs from that covered by national inventories since emission estimates are based on the fuel consumed and include emissions from international shipping and aviation. Fuel consumption data were collected from local authorities, institutions and industry. Emission factors have been selected from relevant

Improved attribution of climate forcing to emissions by pollutant and sector

Science.gov (United States)

Shindell, D. T.

2009-12-01

Evaluating multi-component climate change mitigation strategies requires knowledge of the diverse direct and indirect effects of emissions. Methane, ozone and aerosols are linked through atmospheric chemistry so that emissions of a single pollutant can affect several species. I will show new calculations of atmospheric composition changes, radiative forcing, and the global warming potential (GWP) for increased emissions of tropospheric ozone and aerosol precursors in a coupled composition-climate model. The results demonstrate that gas-aerosol interactions substantially alter the relative importance of the various emissions, suggesting revisions to the GWPs used in international carbon trading. Additionally, I will present results showing how the net climate impact of particular activities depends strongly upon non-CO2 forcing agents for some sectors. These results will be highlighted by discussing the interplay between air quality emissions controls and climate for the case of emissions from coal-fired power plants. The changing balance between CO2 and air quality pollutants from coal plants may have contributed to the 20th century spatial and temporal patterns of climate change, and is likely to continue to do so as more and more plants are constructed in Asia.

A dynamic, climate-driven model of Rift Valley fever

Directory of Open Access Journals (Sweden)

Joseph Leedale

2016-03-01

Full Text Available Outbreaks of Rift Valley fever (RVF in eastern Africa have previously occurred following specific rainfall dynamics and flooding events that appear to support the emergence of large numbers of mosquito vectors. As such, transmission of the virus is considered to be sensitive to environmental conditions and therefore changes in climate can impact the spatiotemporal dynamics of epizootic vulnerability. Epidemiological information describing the methods and parameters of RVF transmission and its dependence on climatic factors are used to develop a new spatio-temporal mathematical model that simulates these dynamics and can predict the impact of changes in climate. The Liverpool RVF (LRVF model is a new dynamic, process-based model driven by climate data that provides a predictive output of geographical changes in RVF outbreak susceptibility as a result of the climate and local livestock immunity. This description of the multi-disciplinary process of model development is accessible to mathematicians, epidemiological modellers and climate scientists, uniting dynamic mathematical modelling, empirical parameterisation and state-of-the-art climate information.

Towards real energy economics: Energy policy driven by life-cycle carbon emission

International Nuclear Information System (INIS)

Kenny, R.; Law, C.; Pearce, J.M.

2010-01-01

Alternative energy technologies (AETs) have emerged as a solution to the challenge of simultaneously meeting rising electricity demand while reducing carbon emissions. However, as all AETs are responsible for some greenhouse gas (GHG) emissions during their construction, carbon emission 'Ponzi Schemes' are currently possible, wherein an AET industry expands so quickly that the GHG emissions prevented by a given technology are negated to fabricate the next wave of AET deployment. In an era where there are physical constraints to the GHG emissions the climate can sustain in the short term this may be unacceptable. To provide quantitative solutions to this problem, this paper introduces the concept of dynamic carbon life-cycle analyses, which generate carbon-neutral growth rates. These conceptual tools become increasingly important as the world transitions to a low-carbon economy by reducing fossil fuel combustion. In choosing this method of evaluation it was possible to focus uniquely on reducing carbon emissions to the recommended levels by outlining the most carbon-effective approach to climate change mitigation. The results of using dynamic life-cycle analysis provide policy makers with standardized information that will drive the optimization of electricity generation for effective climate change mitigation.

Emission Data For Climate-Chemistry Interactions

Science.gov (United States)

Smith, S. J.

2012-12-01

Data on anthropogenic and natural emissions of reactive species are a critical input for studies of atmospheric chemistry and climate. The availability and characteristics of anthropogenic emissions data that can be used for such studies are reviewed and pathways for future work discuss Global and regional datasets for historical and future emissions are available, but their characteristics and applicability for specific studies differ. For the first time, a coordinated set of historical emissions (Lamarque et al 2010) and the future projections (van Vuurren et al. 2011) have been developed for use in the CMIP5 and ACCMIP long-term simulation comparison projects. These data have decadal resolution and were designed for long-term, global simulations. These data, however, lack finer-scale spatial and temporal detail that might be needed for some studies. Robust and timely updates of emissions data is generally lacking, although recent updates will be presented. While historical emission data is often treated as known, emissions are uncertain, even though this uncertainty is rarely quantified. Uncertainty varies by species and location. Inverse modeling is starting to indicate where emission data may be uncertain, which opens the way to improving these data overall. Further interaction between the chemistry modeling and inventory development communities are needed. Future projections are intrinsically uncertain, and while institutions and processes are in place to develop and review long-term century-scale scenarios, a need has remained for a wider range in shorter-term (e.g., several decade) projections. Emissions and scenario development communities have been working to fill this need. Communication across disciplines of the assumptions embedded in emissions projections remains a challenge. Atmospheric chemistry models are a central tool needed for studying chemistry-climate interactions. Simpler models, however, are also needed in order to examine interactions

Contemporary white-band disease in Caribbean corals driven by climate change

Science.gov (United States)

Randall, C. J.; van Woesik, R.

2015-04-01

Over the past 40 years, two of the dominant reef-building corals in the Caribbean, Acropora palmata and Acropora cervicornis, have experienced unprecedented declines. That loss has been largely attributed to a syndrome commonly referred to as white-band disease. Climate change-driven increases in sea surface temperature (SST) have been linked to several coral diseases, yet, despite decades of research, the attribution of white-band disease to climate change remains unknown. Here we hindcasted the potential relationship between recent ocean warming and outbreaks of white-band disease on acroporid corals. We quantified eight SST metrics, including rates of change in SST and contemporary thermal anomalies, and compared them with records of white-band disease on A. palmata and A. cervicornis from 473 sites across the Caribbean, surveyed from 1997 to 2004. The results of our models suggest that decades-long climate-driven changes in SST, increases in thermal minima, and the breach of thermal maxima have all played significant roles in the spread of white-band disease. We conclude that white-band disease has been strongly coupled with thermal stresses associated with climate change, which has contributed to the regional decline of these once-dominant reef-building corals.

Distributional aspects of emissions in climate change integrated assessment models

International Nuclear Information System (INIS)

Cantore, Nicola

2011-01-01

The recent failure of Copenhagen negotiations shows that concrete actions are needed to create the conditions for a consensus over global emission reduction policies. A wide coalition of countries in international climate change agreements could be facilitated by the perceived fairness of rich and poor countries of the abatement sharing at international level. In this paper I use two popular climate change integrated assessment models to investigate the path and decompose components and sources of future inequality in the emissions distribution. Results prove to be consistent with previous empirical studies and robust to model comparison and show that gaps in GDP across world regions will still play a crucial role in explaining different countries contributions to global warming. - Research highlights: → I implement a scenario analysis with two global climate change models. → I analyse inequality in the distribution of emissions. → I decompose emissions inequality components. → I find that GDP per capita is the main Kaya identity source of emissions inequality. → Current rich countries will mostly remain responsible for emissions inequality.

Vegetation-mediated Climate Impacts on Historical and Future Ozone Air Quality

Science.gov (United States)

Tai, A. P. K.; Fu, Y.; Mickley, L. J.; Heald, C. L.; Wu, S.

2014-12-01

Changes in climate, natural vegetation and human land use are expected to significantly influence air quality in the coming century. These changes and their interactions have important ramifications for the effectiveness of air pollution control strategies. In a series of studies, we use a one-way coupled modeling framework (GEOS-Chem driven by different combinations of historical and future meteorological, land cover and emission data) to investigate the effects of climate-vegetation changes on global and East Asian ozone air quality from 30 years ago to 40 years into the future. We find that future climate and climate-driven vegetation changes combine to increase summertime ozone by 2-6 ppbv in populous regions of the US, Europe, East Asia and South Asia by year 2050, but including the interaction between CO2 and biogenic isoprene emission reduces the climate impacts by more than half. Land use change such as cropland expansion has the potential to either mostly offset the climate-driven ozone increases (e.g., in the US and Europe), or greatly increase ozone (e.g., in Southeast Asia). The projected climate-vegetation effects in East Asia are particularly uncertain, reflecting a less understood ozone production regime. We thus further study how East Asian ozone air quality has evolved since the early 1980s in response to climate, vegetation and emission changes to shed light on its likely future course. We find that warming alone has led to a substantial increase in summertime ozone in populous regions by 1-4 ppbv. Despite significant cropland expansion and urbanization, increased summertime leafiness of vegetation in response to warming and CO2 fertilization has reduced ozone by 1-2 ppbv, driven by enhanced ozone deposition dominating over elevated biogenic emission and partially offsetting the warming effect. The historical role of CO2-isoprene interaction in East Asia, however, remains highly uncertain. Our findings demonstrate the important roles of land cover

Climate and health implications of future aerosol emission scenarios

Science.gov (United States)

Partanen, Antti-Ilari; Landry, Jean-Sébastien; Damon Matthews, H.

2018-02-01

Anthropogenic aerosols have a net cooling effect on climate and also cause adverse health effects by degrading air quality. In this global-scale sensitivity study, we used a combination of the aerosol-climate model ECHAM-HAMMOZ and the University of Victoria Earth System Climate Model to assess the climate and health effects of aerosols emissions from three Representative Concentration Pathways (RCP2.6, RCP4.5, and RCP8.5) and two new (LOW and HIGH) aerosol emission scenarios derived from RCP4.5, but that span a wider spectrum of possible future aerosol emissions. All simulations had CO2 emissions and greenhouse gas forcings from RCP4.5. Aerosol forcing declined similarly in the standard RCP aerosol emission scenarios: the aerosol effective radiative forcing (ERF) decreased from -1.3 W m-2 in 2005 to between -0.1 W m-2 and -0.4 W m-2 in 2100. The differences in ERF were substantially larger between LOW (-0.02 W m-2 in 2100) and HIGH (-0.8 W m-2) scenarios. The global mean temperature difference between the simulations with standard RCP aerosol emissions was less than 0.18 °C, whereas the difference between LOW and HIGH reached 0.86 °C in 2061. In LOW, the rate of warming peaked at 0.48 °C per decade in the 2030s, whereas in HIGH it was the lowest of all simulations and never exceeded 0.23 °C per decade. Using present-day population density and baseline mortality rates for all scenarios, PM2.5-induced premature mortality was 2 371 800 deaths per year in 2010 and 525 700 in 2100 with RCP4.5 aerosol emissions; in HIGH, the premature mortality reached its maximum value of 2 780 800 deaths per year in 2030, whereas in LOW the premature mortality at 2030 was below 299 900 deaths per year. Our results show potential trade-offs in aerosol mitigation with respect to climate change and public health as ambitious reduction of aerosol emissions considerably increased warming while decreasing mortality.

Greenhouse gas and livestock emissions and climate change

DEFF Research Database (Denmark)

Caro, Dario

2018-01-01

The paper summarizes the current knowledge about the impact of livestock sector on climate change. The main sources of greenhouse gas (GHG) emissions from livestock are described and the contribution of livestock sector to the global GHG emissions is presented on the basis of the latest results...... obtained from the scientific research. The most recent mitigation strategies for reducing greenhouse gas emissions from livestock sector are also discussed. The paper aims to provide a general overview of an emergent environmental issue such as the impact of livestock sector on climate change. While...... the paper is easy to understand for non-expert readers, it may also be a relevant reference point for academic researchers and for policy makers aimed at achieving the sustainability of livestock/food sector....

Integration of Linear Dynamic Emission and Climate Models with Air Traffic Simulations

Science.gov (United States)

Sridhar, Banavar; Ng, Hok K.; Chen, Neil Y.

2012-01-01

Future air traffic management systems are required to balance the conflicting objectives of maximizing safety and efficiency of traffic flows while minimizing the climate impact of aviation emissions and contrails. Integrating emission and climate models together with air traffic simulations improve the understanding of the complex interaction between the physical climate system, carbon and other greenhouse gas emissions and aviation activity. This paper integrates a national-level air traffic simulation and optimization capability with simple climate models and carbon cycle models, and climate metrics to assess the impact of aviation on climate. The capability can be used to make trade-offs between extra fuel cost and reduction in global surface temperature change. The parameters in the simulation can be used to evaluate the effect of various uncertainties in emission models and contrails and the impact of different decision horizons. Alternatively, the optimization results from the simulation can be used as inputs to other tools that monetize global climate impacts like the FAA s Aviation Environmental Portfolio Management Tool for Impacts.

The Net Climate Impact of Coal-Fired Power Plant Emissions

Science.gov (United States)

Shindell, D.; Faluvegi, G.

2010-01-01

Coal-fired power plants influence climate via both the emission of long-lived carbon dioxide (CO2) and short-lived ozone and aerosol precursors. Using a climate model, we perform the first study of the spatial and temporal pattern of radiative forcing specifically for coal plant emissions. Without substantial pollution controls, we find that near-term net global mean climate forcing is negative due to the well-known aerosol masking of the effects of CO2. Imposition of pollution controls on sulfur dioxide and nitrogen oxides leads to a rapid realization of the full positive forcing from CO2, however. Long-term global mean forcing from stable (constant) emissions is positive regardless of pollution controls. Emissions from coal-fired power plants until 1970, including roughly 1/3 of total anthropogenic CO2 emissions, likely contributed little net global mean climate forcing during that period though they may have induce weak Northern Hemisphere mid-latitude (NHml) cooling. After that time many areas imposed pollution controls or switched to low sulfur coal. Hence forcing due to emissions from 1970 to 2000 and CO2 emitted previously was strongly positive and contributed to rapid global and especially NHml warming. Most recently, new construction in China and India has increased rapidly with minimal application of pollution controls. Continuation of this trend would add negative near-term global mean climate forcing but severely degrade air quality. Conversely, following the Western and Japanese pattern of imposing air quality pollution controls at a later time could accelerate future warming rates, especially at NHmls. More broadly, our results indicate that due to spatial and temporal inhomogeneities in forcing, climate impacts of multi-pollutant emissions can vary strongly from region to region and can include substantial effects on maximum rate-of-change, neither of which are captured by commonly used global metrics. The method we introduce here to estimate

Impact of biogenic emissions on feedbacks in the climate system

Science.gov (United States)

Krüger, Olaf

2017-04-01

Impact of biogenic emissions on feedbacks in the climate system Bio-geophysical feedback between marine or continental ecosystems and the atmosphere potentially can alter climate change. A prominent feedback loop which is under discussion since 1983 bases on the emission of biologically produced gases - molecular oxygen, sulphur containing compounds and possibly isoprene, supersaturated in oceanic waters - into the marine troposphere. These by-products of phytoplankton metabolism lead to aerosol production and procure sustained influence on climate via modulation of cloud optical properties. In this contribution some findings related to the above mentioned climate processes are presented with special emphasis on marine ecosystems. A comparison of marine and continental ecosystems is made and different processes with major impact on feedbacks in the climate system are discussed.

Effects of Kosovo's energy use scenarios and associated gas emissions on its climate change and sustainable development

International Nuclear Information System (INIS)

Kabashi, Skender; Bekteshi, Sadik; Ahmetaj, Skender; Kabashi, Gazmend; Najdovski, Dimitrij; Zidansek, Aleksander; Slaus, Ivo

2011-01-01

Climate change will be the first truly global challenge for sustainability. Energy production and consumption from fossil fuels has central role in respect to climate change, but also to sustainability in general. Because climate change is regionally driven with global consequences and is a result of economic imperatives and social values, it requires a redefinition as to the balance of these outcomes globally and regionally in Kosovo. Kosovo as one of the richest countries with lignite in Europe, with 95-97% of the electric power production from lignite and with 90% of vehicles over 10 years old, represents one of the regions with the greatest ratio of CO 2 emissions per unit of GDP, as well as one of the countries with the most polluted atmosphere in Europe. The modelling is carried out regionally for Kosovo for two dynamical systems which are the main emitters of greenhouse gases (CO 2 , CH 4 , NO x , etc.) and air pollutants (CO, SO 2 , dust CH x , etc.): electricity generation and transportation emissions systems, for the time period 2000-2025. Various energy scenarios of the future are shown. We demonstrate that a transition to environmentally compatible sustainable energy use in Kosovo is possible. Implementing the emission reduction policies and introducing new technologies in electrical power production and transportation in Kosovo ensure a sustainable future development in Kosovo, electric power production and transport that become increasingly environmentally compatible.

Greenness and Carbon Stocks of Mangroves: A climate-driven Effect

Science.gov (United States)

Lule, A. V.; Colditz, R. R.; Herrera-Silveira, J.; Guevara, M.; Rodriguez-Zuniga, M. T.; Cruz, I.; Ressl, R.; Vargas, R.

2017-12-01

Mangroves cover less than 1% of the earth's surface and are one o­­­f the most productive ecosystems of the world. They are highly vulnerable to climate variability due to their sensitivity to environmental changes; therefore, there are scientific and societal needs to designed frameworks to assess mangrove's vulnerability. We study the relationship between climate drivers, canopy greenness and carbon stocks to quantify a potential climate-driven effect on mangrove carbon dynamics. We identify greenness trends and their relationships with climate drivers and carbon stocks throughout 15 years (2001-2015) across mangrove forests of Mexico. We defined several categories for mangroves: a) Arid mangroves with superficial water input (ARsw); b) Humid mangroves with interior or underground water input (HUiw); and c) Humid mangroves with superficial water input (HUsw). We found a positive significant trend of greenness for ARsw and HUsw categories (pmangrove's categories (pmangrove categories showed higher greenness values during winter; which is likely driven by temperature with a lag of -3 to -5 months (r2 > 0.69). Precipitation and temperature drive canopy greenness only across HUsw. Regarding carbon stocks, the HUiw shows the lower amount of aboveground carbon (AGC; 12.7 Mg C ha-1) and the higher belowground carbon (BGC; 219 Mg C ha-1). The HUsw shows the higher amount of AGC (169.5 Mg C ha-1) and the ARsw the lower of BGC (92.4 Mg C ha-1). Climate drivers are better related with canopy greenness and AGC for both humid mangrove categories (r2 > 0.48), while the relationship of BGC and canopy greenness is lower for all categories (r2 mangrove's ecosystem function and environmental services, as well as their potential vulnerability to climate variability.

Delayed electron emission in strong-field driven tunnelling from a metallic nanotip in the multi-electron regime

Science.gov (United States)

Yanagisawa, Hirofumi; Schnepp, Sascha; Hafner, Christian; Hengsberger, Matthias; Kim, Dong Eon; Kling, Matthias F.; Landsman, Alexandra; Gallmann, Lukas; Osterwalder, Jürg

2016-01-01

Illuminating a nano-sized metallic tip with ultrashort laser pulses leads to the emission of electrons due to multiphoton excitations. As optical fields become stronger, tunnelling emission directly from the Fermi level becomes prevalent. This can generate coherent electron waves in vacuum leading to a variety of attosecond phenomena. Working at high emission currents where multi-electron effects are significant, we were able to characterize the transition from one regime to the other. Specifically, we found that the onset of laser-driven tunnelling emission is heralded by the appearance of a peculiar delayed emission channel. In this channel, the electrons emitted via laser-driven tunnelling emission are driven back into the metal, and some of the electrons reappear in the vacuum with some delay time after undergoing inelastic scattering and cascading processes inside the metal. Our understanding of these processes gives insights on attosecond tunnelling emission from solids and should prove useful in designing new types of pulsed electron sources. PMID:27786287

Evaluate transport processes in MERRA driven chemical transport models using updated 222Rn emission inventories and global observations

Science.gov (United States)

Zhang, B.; Liu, H.; Crawford, J. H.; Fairlie, T. D.; Chen, G.; Chambers, S. D.; Kang, C. H.; Williams, A. G.; Zhang, K.; Considine, D. B.; Payer Sulprizio, M.; Yantosca, R.

2015-12-01

Convective and synoptic processes play a major role in determining the transport and distribution of trace gases and aerosols in the troposphere. The representation of these processes in global models (at ~100-1000 km horizontal resolution) is challenging, because convection is a sub-grid process and needs to be parameterized, while synoptic processes are close to the grid scale. Depending on the parameterization schemes used in climate models, the role of convection in transporting trace gases and aerosols may vary from model to model. 222Rn is a chemically inert and radioactive gas constantly emitted from soil and has a half-life (3.8 days) comparable to synoptic timescale, which makes it an effective tracer for convective and synoptic transport. In this study, we evaluate the convective and synoptic transport in two chemical transport models (GMI and GEOS-Chem), both driven by the NASA's MERRA reanalysis. Considering the uncertainties in 222Rn emissions, we incorporate two more recent scenarios with regionally varying 222Rn emissions into GEOS-Chem/MERRA and compare the simulation results with those using the relatively uniform 222Rn emissions in the standard model. We evaluate the global distribution and seasonality of 222Rn concentrations simulated by the two models against an extended collection of 222Rn observations from 1970s to 2010s. The intercomparison will improve our understanding of the spatial variability in global 222Rn emissions, including the suspected excessive 222Rn emissions in East Asia, and provide useful feedbacks on 222Rn emission models. We will assess 222Rn vertical distributions at different latitudes in the models using observations at surface sites and in the upper troposphere and lower stratosphere. Results will be compared with previous models driven by other meteorological fields (e.g., fvGCM and GEOS4). Since the decay of 222Rn is the source of 210Pb, a useful radionuclide tracer attached to submicron aerosols, improved

The effect of education on climate change risks

Science.gov (United States)

O'Neill, B. C.; KC, S.; Jiang, L.; Fuchs, R.; Pachauri, S.; Ren, X.; Zhang, T.; Laidlaw, E.

2017-12-01

Changes in the demographic and socio-economic compositions of populations are relevant to the climate change issue because these characteristics can be important determinants both of the capacity to adapt to climate change impacts as well as of energy use and greenhouse gas emissions, and therefore climate change. However, the incorporation of major trends such as aging, urbanization, and changes in household size into projections of future energy use and emissions is rare. Here we build on our previous work in this area by exploring the implications of future changes in educational attainment for the climate issue. Changes in the educational composition of the population may reduce the vulnerability of the population to climate change impacts, reducing risks. However they may also have effects on energy use and land use, and the resulting greenhouse gas emissions that drive climate change and increase risks. The direction of the effect of education on emissions is itself ambiguous. On the one hand, improvements in education can be expected to lead to faster fertility decline and slower population growth which, all else equal, would be expected to reduce emissions. On the other hand, education can also be expected to lead to faster economic growth, which would tend to increase emissions, and also to changes in consumption patterns. We employ iPETS, an integrated assessment model that includes a multi-region model of the world economy, driven with a new set of country-specific projections of future educational composition, to test the net effect of education on energy use and emissions on four world regions (China, India, Latin America, and Rest of Asia + Middle East) and therefore on climate. We also calculate the Human Development Index (HDI) for each region resulting from these scenarios, as an indicator of vulnerability to climate impacts. We find that the net effect of improved education is to increase emissions in the medium term driven primarily by increased

Towards a climate-dependent paradigm of ammonia emission and deposition

Energy Technology Data Exchange (ETDEWEB)

Sutton, M.A.; Reis, S.; Riddick, S.N.; Dragosits, U.; Nemitz, E.; Tang, Y.S.; Braban, C.F.; Vieno, M.; Dore, A.J.; Mitchell, R.F.; Wanless, S.; Daunt, F.; Fowler, D. [NERC Centre for Ecology and Hydrology Edinburgh, Bush Estate, Penicuik EH26 0QB (United Kingdom); Blackall, T.D. [Department of Geography, Strand Campus, Kings College London, London WC2R 2LS (United Kingdom); Theobald, M.R. [Higher Technical School of Agricultural Engineering, Technical University of Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain); Milford, C. [Izana Atmospheric Research Center, Meteorological State Agency of Spain (AEMET), Santa Cruz de Tenerife 38071 (Spain); Flechard, C.R. [INRA, Agrocampus Ouest, UMR 1069 SAS, 65 rue de St. Brieuc, 35042 Rennes Cedex (France); Loubet, B.; Massad, R.; Cellier, P.; Personne, E. [UMR INRA-AgroParisTech Environnement et Grandes Cultures, 78850 Thiverval-Grignon (France); Coheur, P.F.; Clarisse, L.; Van Damme, M.; Ngadi, Y. [Spectroscopie de l' atmosphere, Chimie Quantique et Photophysique, Universite Libre de Bruxelles (ULB), 50 avenue F. D. Roosevelt, 1050 Brussels (Belgium); Clerbaux, C. [Universite Paris 06, Universite Versailles-St. Quentin, UMR8190, CNRS/INSU, LATMOS-IPSL, Paris (France); Geels, C.; Hertel, O. [Department of Environmental Science, Aarhus University, P.O. Box 358, Frederiksborgvej 399, 4000 Roskilde (Denmark); Ambelas Skjoeth, C. [National Pollen and Aerobiology Research Unit, University of Worcester, Henwick Grove, Worcester WR2 6AJ (United Kingdom); Wichink Kruit, R.J. [TNO, Climate, Air and Sustainability, P.O. Box 80015, 3508 TA Utrecht (Netherlands); Pinder, R.W.; Bash, J.O.; Walker, J.T. [US Environmental Protection Agency, Office of Research and Development, Research Triangle Park, 109 T.W. Alexander Drive, Durham, NC 27711 (United States); Simpson, D. [Norwegian Meteorological Institute, EMEP MSC-W, P.O. Box 43-Blindern, 0313 Oslo (Norway); Horvath, L. [Plant Ecology Research Group of Hungarian Academy of Sciences, Institute of Botany and Ecophysiology, Szent Istvan University, Pater K. utca 1, 2100 Goedoello (Hungary); Misselbrook, T.H. [Rothamsted Research, Sustainable Soils and Grassland Systems, North Wyke, Okehampton EX20 2SB (United Kingdom); Bleeker, A. [Energy Research Centre of the Netherlands (ECN), P.O. Box 1, 1755 ZG Petten (Netherlands); Dentener, F. [European Commission, DG Joint Research Centre, via Enrico Fermi 2749, 21027 Ispra (Italy); De Vries, W. [Alterra, Wageningen University and Research Centre, Droevendaalsesteeg 4, 6708 PB Wageningen (Netherlands)

2013-07-15

Existing descriptions of bi-directional ammonia (NH3) land-atmosphere exchange incorporate temperature and moisture controls, and are beginning to be used in regional chemical transport models. However, such models have typically applied simpler emission factors to upscale the main NH3 emission terms. While this approach has successfully simulated the main spatial patterns on local to global scales, it fails to address the environment- and climate-dependence of emissions. To handle these issues, we outline the basis for a new modelling paradigm where both NH3 emissions and deposition are calculated online according to diurnal, seasonal and spatial differences in meteorology. We show how measurements reveal a strong, but complex pattern of climatic dependence, which is increasingly being characterized using ground-based NH3 monitoring and satellite observations, while advances in process-based modelling are illustrated for agricultural and natural sources, including a global application for seabird colonies. A future architecture for NH3 emission-deposition modelling is proposed that integrates the spatio-temporal interactions, and provides the necessary foundation to assess the consequences of climate change. Based on available measurements, a first empirical estimate suggests that 5{sup o}C warming would increase emissions by 42 per cent (28-67%). Together with increased anthropogenic activity, global NH3 emissions may increase from 65 (45-85) Tg N in 2008 to reach 132 (89-179) Tg by 2100.

Emissions Trading Regimes and Incentives to Participate in International Climate Agreements

International Nuclear Information System (INIS)

Buchner, B.; Carraro, C.

2003-11-01

This paper analyses whether different emissions trading regimes provide different incentives to participate in a cooperative climate agreement. Different incentive structures are discussed for those countries, namely the US, Russia and China, that are most important in the climate negotiation process. Our analysis confirms the conjecture that, by appropriately designing the emission trading regime, it is possible to enhance the incentives to participate in a climate agreement. Therefore, participation and optimal policy should be jointly analysed. Moreover, our results show that the US, Russia and China have different most preferred climate coalitions and therefore adopt conflicting negotiation strategies

Arctic Vegetation under Climate Change – Biogenic Volatile Organic Compound Emissions and Leaf Anatomy

DEFF Research Database (Denmark)

Schollert, Michelle

common arctic plant species, illustrating the great importance of vegetation composition for determining ecosystem BVOC emissions. Additionally, this thesis assesses the BVOC emission responses in common arctic plant species to effects of climate change: warming, shading and snow addition. Against...... treatment effects on BVOC emissions. Furthermore, the anatomy of arctic plants seems to respond differently to warming than species at lower latitudes. The results in this thesis demonstrate the complexity of the effects of climate change on BVOC emissions and leaf anatomy of arctic plant species...... emissions from the arctic region are assumed to be low, but data from the region is lacking. BVOC emissions are furthermore expected to change drastically due to the rapidly proceeding climate change in the Arctic, which can provide a feedback to climate warming of unknown direction and magnitude. BVOC...

Relevance of emissions timing in biofuel greenhouse gases and climate impacts.

Science.gov (United States)

Schwietzke, Stefan; Griffin, W Michael; Matthews, H Scott

2011-10-01

Employing life cycle greenhouse gas (GHG) emissions as a key performance metric in energy and environmental policy may underestimate actual climate change impacts. Emissions released early in the life cycle cause greater cumulative radiative forcing (CRF) over the next decades than later emissions. Some indicate that ignoring emissions timing in traditional biofuel GHG accounting overestimates the effectiveness of policies supporting corn ethanol by 10-90% due to early land use change (LUC) induced GHGs. We use an IPCC climate model to (1) estimate absolute CRF from U.S. corn ethanol and (2) quantify an emissions timing factor (ETF), which is masked in the traditional GHG accounting. In contrast to earlier analyses, ETF is only 2% (5%) over 100 (50) years of impacts. Emissions uncertainty itself (LUC, fuel production period) is 1-2 orders of magnitude higher, which dwarfs the timing effect. From a GHG accounting perspective, emissions timing adds little to our understanding of the climate impacts of biofuels. However, policy makers should recognize that ETF could significantly decrease corn ethanol's probability of meeting the 20% GHG reduction target in the 2007 Energy Independence and Security Act. The added uncertainty of potentially employing more complex emissions metrics is yet to be quantified.

Greenhouse gas emissions considered responsible for climate change: Environmental indicators

International Nuclear Information System (INIS)

Vialetto, G.; Venanzi, M.; Gaudioso, D.

1993-09-01

This paper concerns the more significant environmental indicators related to the emissions of radiatively and chemically/photochemically active trace gases. Reference is made to the preliminary work of the Intergovernmental Panel on Climate Change (IPCC) and to the proposals made in the framework of the international negotiation on climate change. Aiming to contribute to the definition of a national strategy for the reduction of greenhouse gases emissions, this paper proposes a possible application of the indicators. The calculation of the indicators is based on the emission estimate performed by ENEA (Italian National Agency for Energy, New Technologies and the Environment) for the Report on the State of the Environment edited by the Italian Ministry of the Environment. Finally, the paper suggests an application of such indicators for the international negotiation, in the framework of the Italian proposal for the Convention on climate change

Regional emission metrics for short-lived climate forcers from multiple models

Directory of Open Access Journals (Sweden)

B. Aamaas

2016-06-01

Full Text Available For short-lived climate forcers (SLCFs, the impact of emissions depends on where and when the emissions take place. Comprehensive new calculations of various emission metrics for SLCFs are presented based on radiative forcing (RF values calculated in four different (chemical-transport or coupled chemistry–climate models. We distinguish between emissions during summer (May–October and winter (November–April for emissions in Europe and East Asia, as well as from the global shipping sector and global emissions. The species included in this study are aerosols and aerosol precursors (BC, OC, SO2, NH3, as well as ozone precursors (NOx, CO, VOCs, which also influence aerosols to a lesser degree. Emission metrics for global climate responses of these emissions, as well as for CH4, have been calculated using global warming potential (GWP and global temperature change potential (GTP, based on dedicated RF simulations by four global models. The emission metrics include indirect cloud effects of aerosols and the semi-direct forcing for BC. In addition to the standard emission metrics for pulse and sustained emissions, we have also calculated a new emission metric designed for an emission profile consisting of a ramping period of 15 years followed by sustained emissions, which is more appropriate for a gradual implementation of mitigation policies.For the aerosols, the emission metric values are larger in magnitude for emissions in Europe than East Asia and for summer than winter. A variation is also observed for the ozone precursors, with largest values for emissions in East Asia and winter for CO and in Europe and summer for VOCs. In general, the variations between the emission metrics derived from different models are larger than the variations between regions and seasons, but the regional and seasonal variations for the best estimate also hold for most of the models individually. Further, the estimated climate impact of an illustrative mitigation

Carbon Countdown. Emissions trading to combat climate change

International Nuclear Information System (INIS)

2006-06-01

The European Emission Trading Scheme (EU ETS) is a crucial cornerstone of climate change policy in Europe and the first international trading system for carbon dioxide (CO2) emissions in the world. The ETS is a major part of the solution to one of the biggest challenges humanity is facing: global warming. A WWF review of Phase 1 of the European Emission Trading Scheme and recommendations to improve its environmental effectiveness and economic efficiency for Phase 2

Seasonal climate change patterns due to cumulative CO2 emissions

Science.gov (United States)

Partanen, Antti-Ilari; Leduc, Martin; Damon Matthews, H.

2017-07-01

Cumulative CO2 emissions are near linearly related to both global and regional changes in annual-mean surface temperature. These relationships are known as the transient climate response to cumulative CO2 emissions (TCRE) and the regional TCRE (RTCRE), and have been shown to remain approximately constant over a wide range of cumulative emissions. Here, we assessed how well this relationship holds for seasonal patterns of temperature change, as well as for annual-mean and seasonal precipitation patterns. We analyzed an idealized scenario with CO2 concentration growing at an annual rate of 1% using data from 12 Earth system models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). Seasonal RTCRE values for temperature varied considerably, with the highest seasonal variation evident in the Arctic, where RTCRE was about 5.5 °C per Tt C for boreal winter and about 2.0 °C per Tt C for boreal summer. Also the precipitation response in the Arctic during boreal winter was stronger than during other seasons. We found that emission-normalized seasonal patterns of temperature change were relatively robust with respect to time, though they were sub-linear with respect to emissions particularly near the Arctic. Moreover, RTCRE patterns for precipitation could not be quantified robustly due to the large internal variability of precipitation. Our results suggest that cumulative CO2 emissions are a useful metric to predict regional and seasonal changes in precipitation and temperature. This extension of the TCRE framework to seasonal and regional climate change is helpful for communicating the link between emissions and climate change to policy-makers and the general public, and is well-suited for impact studies that could make use of estimated regional-scale climate changes that are consistent with the carbon budgets associated with global temperature targets.

Mercury from wildfires: Global emission inventories and sensitivity to 2000-2050 global change

Science.gov (United States)

Kumar, Aditya; Wu, Shiliang; Huang, Yaoxian; Liao, Hong; Kaplan, Jed O.

2018-01-01

We estimate the global Hg wildfire emissions for the 2000s and the potential impacts from the 2000-2050 changes in climate, land use and land cover and Hg anthropogenic emissions by combining statistical analysis with global data on vegetation type and coverage as well as fire activities. Global Hg wildfire emissions are estimated to be 612 Mg year-1. Africa is the dominant source region (43.8% of global emissions), followed by Eurasia (31%) and South America (16.6%). We find significant perturbations to wildfire emissions of Hg in the context of global change, driven by the projected changes in climate, land use and land cover and Hg anthropogenic emissions. 2000-2050 climate change could increase Hg emissions by 14% globally and regionally by 18% for South America, 14% for Africa and 13% for Eurasia. Projected changes in land use by 2050 could decrease the global Hg emissions from wildfires by 13% mainly driven by a decline in African emissions due to significant agricultural land expansion. Future land cover changes could lead to significant increases in Hg emissions over some regions (+32% North America, +14% Africa, +13% Eurasia). Potential enrichment of terrestrial ecosystems in 2050 in response to changes in Hg anthropogenic emissions could increase Hg wildfire emissions globally (+28%) and regionally (+19% North America, +20% South America, +24% Africa, +41% Eurasia). Our results indicate that the future evolution of climate, land use and land cover and Hg anthropogenic emissions are all important factors affecting Hg wildfire emissions in the coming decades.

Climate-driven changes in functional biogeography of Arctic marine fish communities.

Science.gov (United States)

Frainer, André; Primicerio, Raul; Kortsch, Susanne; Aune, Magnus; Dolgov, Andrey V; Fossheim, Maria; Aschan, Michaela M

2017-11-14

Climate change triggers poleward shifts in species distribution leading to changes in biogeography. In the marine environment, fish respond quickly to warming, causing community-wide reorganizations, which result in profound changes in ecosystem functioning. Functional biogeography provides a framework to address how ecosystem functioning may be affected by climate change over large spatial scales. However, there are few studies on functional biogeography in the marine environment, and none in the Arctic, where climate-driven changes are most rapid and extensive. We investigated the impact of climate warming on the functional biogeography of the Barents Sea, which is characterized by a sharp zoogeographic divide separating boreal from Arctic species. Our unique dataset covered 52 fish species, 15 functional traits, and 3,660 stations sampled during the recent warming period. We found that the functional traits characterizing Arctic fish communities, mainly composed of small-sized bottom-dwelling benthivores, are being rapidly replaced by traits of incoming boreal species, particularly the larger, longer lived, and more piscivorous species. The changes in functional traits detected in the Arctic can be predicted based on the characteristics of species expected to undergo quick poleward shifts in response to warming. These are the large, generalist, motile species, such as cod and haddock. We show how functional biogeography can provide important insights into the relationship between species composition, diversity, ecosystem functioning, and environmental drivers. This represents invaluable knowledge in a period when communities and ecosystems experience rapid climate-driven changes across biogeographical regions. Copyright © 2017 the Author(s). Published by PNAS.

Quantifying the climate impact of emissions from land-based transport in Germany

OpenAIRE

Hendricks, J.; Righi, M.; Dahlmann, K.; Gottschaldt, K.-D.; Grewe, V.; Ponater, M.; Sausen, R.; Heinrichs, D.; Winkler, C.; Wolfermann, A.; Kampffmeyer, T.; Friedrich, R; Klötzke, M.; Kugler, U.

2017-01-01

Although climate change is a global problem, specific mitigation measures are frequently applied on regional or national scales only. This is the case in particular for measures to reduce the emissions of land-based transport, which is largely characterized by regional or national systems with independent infrastructure, organization, and regulation. The climate perturbations caused by regional transport emissions are small compared to those resulting from global emissions. Consequently, they...

The climate fund. Some notions on the socio-economic impacts of greenhouse gas emissions and emission reductions in an international context

International Nuclear Information System (INIS)

Tol, R.S.J.; Van der Burg, T.; Jansen, H.M.A.; Verbruggen, H.

1995-05-01

The title project investigates the possibility of setting up an international climate fund and the way in which this could be arranged. A climate fund is a potential method to enhance the efficiency and efficacy of the reduction of the increase in the amount of greenhouse gases (GHGs) in the atmosphere. It would allow countries to transfer capital, for instance through the here proposed climate fund, and to redistribute the damages caused by global warming. This project focuses on the economic aspects of a climate fund, although some attention will also be given to its political feasibility. The system of tradeable emission permits, of which joint implementation is often seen as a pilot phase, presumes that fixed emission targets exist. In this report the emissions are not prefixed, but optimised in a cost-benefit analysis in which the impact of international capital transfer is examined. In order to determine the impact of international capital transfer on the efficiency and efficacy on optimal greenhouse gas emission reduction, three building blocks are needed. The first block concerns the costs of climate change, or the benefits of climate change control. The second block concerns the costs of emission reduction. The third block is the model to integrate costs and benefits, and calculate the optimal emission control with and without international capital transfers. The project is split into four conceptual phases. In the first phase, a literature survey has been performed of the socio-economic costs and benefits of greenhouse gas emission reductions, with a particular focus on the international distribution of costs and benefits. In the second phase, the costs and benefits are modelled in the Climate Framework for Uncertainty, Negotiation and Distribution (FUND). In the third phase the optimal emission reductions are calculated with and without international capital transfers in several game-theoretic settings. (Abstract Truncated)

Doubled volatile organic compound emissions from subarctic tundra under simulated climate warming.

Science.gov (United States)

Faubert, Patrick; Tiiva, Päivi; Rinnan, Asmund; Michelsen, Anders; Holopainen, Jarmo K; Rinnan, Riikka

2010-07-01

*Biogenic volatile organic compound (BVOC) emissions from arctic ecosystems are important in view of their role in global atmospheric chemistry and unknown feedbacks to global warming. These cold ecosystems are hotspots of climate warming, which will be more severe here than averaged over the globe. We assess the effects of climatic warming on non-methane BVOC emissions from a subarctic heath. *We performed ecosystem-based chamber measurements and gas chromatography-mass spectrometry (GC-MS) analyses of the BVOCs collected on adsorbent over two growing seasons at a wet subarctic tundra heath hosting a long-term warming and mountain birch (Betula pubescens ssp. czerepanovii) litter addition experiment. *The relatively low emissions of monoterpenes and sesquiterpenes were doubled in response to an air temperature increment of only 1.9-2.5 degrees C, while litter addition had a minor influence. BVOC emissions were seasonal, and warming combined with litter addition triggered emissions of specific compounds. *The unexpectedly high rate of release of BVOCs measured in this conservative warming scenario is far above the estimates produced by the current models, which underlines the importance of a focus on BVOC emissions during climate change. The observed changes have implications for ecological interactions and feedback effects on climate change via impacts on aerosol formation and indirect greenhouse effects.

Atmospheric/climatic effects of aircraft emissions

International Nuclear Information System (INIS)

Pueschel, R.F.

1996-01-01

Exhaust emissions from aircraft include oxides of nitrogen (NO x ), water vapor (H 2 O), sulfur dioxide (SO 2 ), carbon dioxide (CO 2 ), carbon monoxide (CO), hydrocarbons (HC) and particles (soot and sulfates). These emissions are small compared to industrial/urban surface emissions. However, because (1) atmospheric residence times of exhaust constituents are longer at altitude, particularly in the stratosphere, than they are in the boundary layer, (2) their background concentrations at altitude are lower than those near the surface, (3) the radiation balance is the more sensitive to atmospheric trace constituents the colder the temperature aloft and (4) inter-hemispheric mixing of aircraft effluents is inhibited, aircraft emissions near and above the tropopause and polewards of 40 degrees latitude can be environmentally critical. That's why atmospheric/climatic effects of aircraft emissions have again received scientific, economic and political scrutiny in the last few years, motivated by growth of subsonic traffic at about 5% per year over the past two decades and the advent of a technologically feasible operation of a supersonic high speed commercial transport (HSCT) fleet

Effects of Kosovo's energy use scenarios and associated gas emissions on its climate change and sustainable development

Energy Technology Data Exchange (ETDEWEB)

Kabashi, Skender; Bekteshi, Sadik; Ahmetaj, Skender [Faculty of Mathematical and Natural Sciences, University of Prishtina (RS); Kabashi, Gazmend [Faculty of Electric Engineering and Computer Sciences, University of Prishtina, Prishtina (RS); Najdovski, Dimitrij [X3DATA, Novi trg 6, Ljubljana (Slovenia); Zidansek, Aleksander [Jozef Stefan Institute and Jozef Stefan International Postgraduate School, Jamova 39, Ljubljana (Slovenia); Slaus, Ivo [R. Boskovic Institute, Bijenicka 54, Zagreb (Croatia)

2011-02-15

Climate change will be the first truly global challenge for sustainability. Energy production and consumption from fossil fuels has central role in respect to climate change, but also to sustainability in general. Because climate change is regionally driven with global consequences and is a result of economic imperatives and social values, it requires a redefinition as to the balance of these outcomes globally and regionally in Kosovo. Kosovo as one of the richest countries with lignite in Europe, with 95-97% of the electric power production from lignite and with 90% of vehicles over 10 years old, represents one of the regions with the greatest ratio of CO{sub 2} emissions per unit of GDP, as well as one of the countries with the most polluted atmosphere in Europe. The modelling is carried out regionally for Kosovo for two dynamical systems which are the main emitters of greenhouse gases (CO{sub 2}, CH{sub 4}, NO{sub x}, etc.) and air pollutants (CO, SO{sub 2}, dust CH{sub x}, etc.): electricity generation and transportation emissions systems, for the time period 2000-2025. Various energy scenarios of the future are shown. We demonstrate that a transition to environmentally compatible sustainable energy use in Kosovo is possible. Implementing the emission reduction policies and introducing new technologies in electrical power production and transportation in Kosovo ensure a sustainable future development in Kosovo, electric power production and transport that become increasingly environmentally compatible. (author)

Prediction of trace gas emissions and their climatic impacts. Some geographical considerations

Energy Technology Data Exchange (ETDEWEB)

Nicholson, S E [Florida State Univ., Dept. ofMeteorology, Tallahassee, FL (United States)

1993-12-31

This paper examines two major areas of uncertainty in the prediction of the impact of trace gas emissions on climate. The first is socioeconomic factors which determine the rate of such processes as resource use, industrial production or land conversion. The second is the feedback between the earth`s land surface and climate. Since the land surface is the source of trace gas emissions, both natural and anthropogenic changes of vegetation will affect the nature and quantity of emissions. This paper demonstrates large-scale land surface changes which have taken place naturally or from human activities, either intentionally or inadvertently, and describes the dwindling availability of natural resources, using water as an example. Vegetation is also examined as both a response to and a determining factor in climate. Hence, the intricate feedback between vegetation and climate complicates any attempt to predict climatic change. Better quantitative assessment of all relationships and processes is required to achieve realistic forecasts of global change. (au) 31 refs.

Towards a climate-dependent paradigm of ammonia emission and deposition

Science.gov (United States)

Sutton, Mark A.; Reis, Stefan; Riddick, Stuart N.; Dragosits, Ulrike; Nemitz, Eiko; Theobald, Mark R.; Tang, Y. Sim; Braban, Christine F.; Vieno, Massimo; Dore, Anthony J.; Mitchell, Robert F.; Wanless, Sarah; Daunt, Francis; Fowler, David; Blackall, Trevor D.; Milford, Celia; Flechard, Chris R.; Loubet, Benjamin; Massad, Raia; Cellier, Pierre; Personne, Erwan; Coheur, Pierre F.; Clarisse, Lieven; Van Damme, Martin; Ngadi, Yasmine; Clerbaux, Cathy; Skjøth, Carsten Ambelas; Geels, Camilla; Hertel, Ole; Wichink Kruit, Roy J.; Pinder, Robert W.; Bash, Jesse O.; Walker, John T.; Simpson, David; Horváth, László; Misselbrook, Tom H.; Bleeker, Albert; Dentener, Frank; de Vries, Wim

2013-01-01

Existing descriptions of bi-directional ammonia (NH3) land–atmosphere exchange incorporate temperature and moisture controls, and are beginning to be used in regional chemical transport models. However, such models have typically applied simpler emission factors to upscale the main NH3 emission terms. While this approach has successfully simulated the main spatial patterns on local to global scales, it fails to address the environment- and climate-dependence of emissions. To handle these issues, we outline the basis for a new modelling paradigm where both NH3 emissions and deposition are calculated online according to diurnal, seasonal and spatial differences in meteorology. We show how measurements reveal a strong, but complex pattern of climatic dependence, which is increasingly being characterized using ground-based NH3 monitoring and satellite observations, while advances in process-based modelling are illustrated for agricultural and natural sources, including a global application for seabird colonies. A future architecture for NH3 emission–deposition modelling is proposed that integrates the spatio-temporal interactions, and provides the necessary foundation to assess the consequences of climate change. Based on available measurements, a first empirical estimate suggests that 5°C warming would increase emissions by 42 per cent (28–67%). Together with increased anthropogenic activity, global NH3 emissions may increase from 65 (45–85) Tg N in 2008 to reach 132 (89–179) Tg by 2100. PMID:23713128

Vehicle emissions of short-lived and long-lived climate forcers: trends and tradeoffs.

Science.gov (United States)

Edwards, Morgan R; Klemun, Magdalena M; Kim, Hyung Chul; Wallington, Timothy J; Winkler, Sandra L; Tamor, Michael A; Trancik, Jessika E

2017-08-24

Evaluating technology options to mitigate the climate impacts of road transportation can be challenging, particularly when they involve a tradeoff between long-lived emissions (e.g., carbon dioxide) and short-lived emissions (e.g., methane or black carbon). Here we present trends in short- and long-lived emissions for light- and heavy-duty transport globally and in the U.S., EU, and China over the period 2000-2030, and we discuss past and future changes to vehicle technologies to reduce these emissions. We model the tradeoffs between short- and long-lived emission reductions across a range of technology options, life cycle emission intensities, and equivalency metrics. While short-lived vehicle emissions have decreased globally over the past two decades, significant reductions in CO 2 will be required by mid-century to meet climate change mitigation targets. This is true regardless of the time horizon used to compare long- and short-lived emissions. The short-lived emission intensities of some low-CO 2 technologies are higher than others, and thus their suitability for meeting climate targets depends sensitively on the evaluation time horizon. Other technologies offer low intensities of both short-lived emissions and CO 2 .

Focus on cumulative emissions, global carbon budgets and the implications for climate mitigation targets

Science.gov (United States)

Damon Matthews, H.; Zickfeld, Kirsten; Knutti, Reto; Allen, Myles R.

2018-01-01

The Environmental Research Letters focus issue on ‘Cumulative Emissions, Global Carbon Budgets and the Implications for Climate Mitigation Targets’ was launched in 2015 to highlight the emerging science of the climate response to cumulative emissions, and how this can inform efforts to decrease emissions fast enough to avoid dangerous climate impacts. The 22 research articles published represent a fantastic snapshot of the state-or-the-art in this field, covering both the science and policy aspects of cumulative emissions and carbon budget research. In this Review and Synthesis, we summarize the findings published in this focus issue, outline some suggestions for ongoing research needs, and present our assessment of the implications of this research for ongoing efforts to meet the goals of the Paris climate agreement.

Climate protection and emission trading in the agriculture; Klimaschutz und Emissionshandel in der Landwirtschaft

Energy Technology Data Exchange (ETDEWEB)

Luenenbuerger, Benjamin

2013-01-15

The percentage of the agriculture in the greenhouse-gas emissions in Germany amounts 7.1% in the year 2010. Despite its importance, climate protection instruments in the area of the German agriculture are still not developed. There are hardly special regulatory, informational or market-based instruments for the climate protection in the agriculture. The question arises whether the emission trading can be a suitable instrument for climate protection in the agriculture. Thus, the opportunities of the emission trading in the agriculture are investigated. Moreover, alternative and additional instruments of climate protection are considered with respect to the agriculture.

Modelling climate change under no-policy and policy emissions pathways

International Nuclear Information System (INIS)

Wigley, T.M.L.

2003-01-01

Future emissions under the SRES scenarios are described as examples of no-climate-policy scenarios. The production of policy scenarios is guided by Article 2 of the UN Framework Convention on Climate Change, which requires stabilization of greenhouse-gas concentrations. It is suggested that the choice of stabilization targets should be governed by the need to avoid dangerous interference with the climate system, while the choice of the pathway towards a given target should be determined by some form of cost-benefit analysis. The WRE (Wigley, Richels and Edmonds) concentration profiles are given as examples of stabilization pathways, and an alternative 'overshoot' pathway is introduced. Probabilistic projections (as probability density functions - pdfs) for global-mean temperature under the SRES scenarios are given. The relative importance of different sources of uncertainty is determined by removing individual sources of uncertainty and examining the change in the output temperature pdf. Emissions and climate sensitivity uncertainties dominate, while carbon cycle, aerosol forcing and ocean mixing uncertainties are shown to be small. It is shown that large uncertainties remain even if the emissions are prescribed. Uncertainties in regional climate change are defined by comparing normalized changes (i.e., changes per 1C global-mean warming) across multiple models and using the inter-model standard deviation as an uncertainty metric. Global-mean temperature projections for the policy case are given using the WRE profiles. Different stabilization targets are considered, and the overshoot case for 550ppm stabilization is used to quantify the effects of pathway differences. It is shown that large emissions reductions (from the no-policy to the policy case) will lead to only relatively small reductions in warming over the next 100 years

Estimates of future climate based on SRES emission scenarios

Energy Technology Data Exchange (ETDEWEB)

Godal, Odd; Sygna, Linda; Fuglestvedt, Jan S.; Berntsen, Terje

2000-02-14

The preliminary emission scenarios in the Special Report on Emission Scenario (SRES) developed by the Intergovernmental Panel on Climate Change (IPCC), will eventually replace the old IS92 scenarios. By running these scenarios in a simple climate model (SCM) we estimate future temperature increase between 1.7 {sup o}C and 2.8 {sup o}C from 1990 to to 2100. The global sea level rise over the same period is between 0.33 m and 0.45 m. Compared to the previous IPCC scenarios (IS92) the SRES scenarios generally results in changes in both development over time and level of emissions, concentrations, radiative forcing, and finally temperature change and sea level rise. The most striking difference between the IS92 scenarios and the SRES scenarios is the lower level of SO{sub 2} emissions. The range in CO{sub 2} emissions is also expected to be narrower in the new scenarios. The SRES scenarios result in a narrower range both for temperature change and sea level rise from 1990 to 2100 compared to the range estimated for the IS92 scenarios. (author)

The Influence of Emission Location on the Magnitude and Spatial Distribution of Aerosols' Climate Effects

Science.gov (United States)

Persad, G.; Caldeira, K.

2017-12-01

The global distribution of anthropogenic aerosol emissions has evolved continuously since the preindustrial era - from 20th century North American and Western European emissions hotspots to present-day South and East Asian ones. With this comes a relocation of the regional radiative, dynamical, and hydrological impacts of aerosol emissions, which may influence global climate differently depending on where they occur. A lack of understanding of this relationship between aerosol emissions' location and their global climate effects, however, obscures the potential influence that aerosols' evolving geographic distribution may have on global and regional climate change—a gap which we address in this work. Using a novel suite of experiments in the CESM CAM5 atmospheric general circulation model coupled to a slab ocean, we systematically test and analyze mechanisms behind the relative climate impact of identical black carbon and sulfate aerosol emissions located in each of 8 past, present, or projected future major emissions regions. Results indicate that historically high emissions regions, such as North America and Western Europe, produce a stronger cooling effect than current and projected future high emissions regions. Aerosol emissions located in Western Europe produce 3 times the global mean cooling (-0.34 °C) as those located in East Africa or India (-0.11 °C). The aerosols' in-situ radiative effects remain relatively confined near the emissions region, but large distal cooling results from remote feedback processes - such as ice albedo and cloud changes - that are excited more strongly by emissions from certain regions than others. Results suggest that aerosol emissions from different countries should not be considered equal in the context of climate mitigation accounting, and that the evolving geographic distribution of aerosol emissions may have a substantial impact on the magnitude and spatial distribution of global climate change.

Dependency of climate change and carbon cycle on CO2 emission pathways

International Nuclear Information System (INIS)

Nohara, Daisuke; Yoshida, Yoshikatsu; Misumi, Kazuhiro; Ohba, Masamichi

2013-01-01

Previous research has indicated that the response of globally average temperature is approximately proportional to cumulative CO 2 emissions, yet evidence of the robustness of this relationship over a range of CO 2 emission pathways is lacking. To address this, we evaluate the dependency of climate and carbon cycle change on CO 2 emission pathways using a fully coupled climate–carbon cycle model. We design five idealized pathways (including an overshoot scenario for cumulative emissions), each of which levels off to final cumulative emissions of 2000 GtC. The cumulative emissions of the overshoot scenario reach 4000 GtC temporarily, subsequently reducing to 2000 GtC as a result of continuous negative emissions. Although we find that responses of climatic variables and the carbon cycle are largely independent of emission pathways, a much weakened Atlantic meridional overturning circulation (AMOC) is projected in the overshoot scenario despite cessation of emissions. This weakened AMOC is enhanced by rapid warming in the Arctic region due to considerable temporary elevation of atmospheric CO 2 concentration and induces the decline of surface air temperature and decrease of precipitation over the northern Atlantic and Europe region. Moreover, the weakened AMOC reduces CO 2 uptake by the Atlantic and Arctic oceans. However, the weakened AMOC contributes little to the global carbon cycle. In conclusion, although climate variations have been found to be dependent on emission pathways, the global carbon cycle is relatively independent of these emission pathways, at least superficially. (letter)

Overfishing reduces resilience of kelp beds to climate-driven catastrophic phase shift.

Science.gov (United States)

Ling, S D; Johnson, C R; Frusher, S D; Ridgway, K R

2009-12-29

A key consideration in assessing impacts of climate change is the possibility of synergistic effects with other human-induced stressors. In the ocean realm, climate change and overfishing pose two of the greatest challenges to the structure and functioning of marine ecosystems. In eastern Tasmania, temperate coastal waters are warming at approximately four times the global ocean warming average, representing the fastest rate of warming in the Southern Hemisphere. This has driven range extension of the ecologically important long-spined sea urchin (Centrostephanus rodgersii), which has now commenced catastrophic overgrazing of productive Tasmanian kelp beds leading to loss of biodiversity and important rocky reef ecosystem services. Coincident with the overgrazing is heavy fishing of reef-based predators including the spiny lobster Jasus edwardsii. By conducting experiments inside and outside Marine Protected Areas we show that fishing, by removing large predatory lobsters, has reduced the resilience of kelp beds against the climate-driven threat of the sea urchin and thus increased risk of catastrophic shift to widespread sea urchin barrens. This shows that interactions between multiple human-induced stressors can exacerbate nonlinear responses of ecosystems to climate change and limit the adaptive capacity of these systems. Management actions focused on reducing the risk of catastrophic phase shift in ecosystems are particularly urgent in the face of ongoing warming and unprecedented levels of predator removal from the world's oceans.

Are fish outside their usual ranges early indicators of climate-driven range shifts?

Science.gov (United States)

Fogarty, Hannah E; Burrows, Michael T; Pecl, Gretta T; Robinson, Lucy M; Poloczanska, Elvira S

2017-05-01

Shifts in species ranges are a global phenomenon, well known to occur in response to a changing climate. New species arriving in an area may become pest species, modify ecosystem structure, or represent challenges or opportunities for fisheries and recreation. Early detection of range shifts and prompt implementation of any appropriate management strategies is therefore crucial. This study investigates whether 'first sightings' of marine species outside their normal ranges could provide an early warning of impending climate-driven range shifts. We examine the relationships between first sightings and marine regions defined by patterns of local climate velocities (calculated on a 50-year timescale), while also considering the distribution of observational effort (i.e. number of sampling days recorded with biological observations in global databases). The marine trajectory regions include climate 'source' regions (areas lacking connections to warmer areas), 'corridor' regions (areas where moving isotherms converge), and 'sink' regions (areas where isotherms locally disappear). Additionally, we investigate the latitudinal band in which first sightings were recorded, and species' thermal affiliations. We found that first sightings are more likely to occur in climate sink and 'divergent' regions (areas where many rapid and diverging climate trajectories pass through) indicating a role of temperature in driving changes in marine species distributions. The majority of our fish first sightings appear to be tropical and subtropical species moving towards high latitudes, as would be expected in climate warming. Our results indicate that first sightings are likely related to longer-term climatic processes, and therefore have potential use to indicate likely climate-driven range shifts. The development of an approach to detect impending range shifts at an early stage will allow resource managers and researchers to better manage opportunities resulting from range

Streamflow in the upper Mississippi river basin as simulated by SWAT driven by 20{sup th} century contemporary results of global climate models and NARCCAP regional climate models

Energy Technology Data Exchange (ETDEWEB)

Takle, Eugene S.; Jha, Manoj; Lu, Er; Arritt, Raymond W.; Gutowski, William J. [Iowa State Univ. Ames, IA (United States)

2010-06-15

We use Soil and Water Assessment Tool (SWAT) when driven by observations and results of climate models to evaluate hydrological quantities, including streamflow, in the Upper Mississippi River Basin (UMRB) for 1981-2003 in comparison to observed streamflow. Daily meteorological conditions used as input to SWAT are taken from (1) observations at weather stations in the basin, (2) daily meteorological conditions simulated by a collection of regional climate models (RCMs) driven by reanalysis boundary conditions, and (3) daily meteorological conditions simulated by a collection of global climate models (GCMs). Regional models used are those whose data are archived by the North American Regional Climate Change Assessment Program (NARCCAP). Results show that regional models correctly simulate the seasonal cycle of precipitation, temperature, and streamflow within the basin. Regional models also capture interannual extremes represented by the flood of 1993 and the dry conditions of 2000. The ensemble means of both the GCM-driven and RCM-driven simulations by SWAT capture both the timing and amplitude of the seasonal cycle of streamflow with neither demonstrating significant superiority at the basin level. (orig.)

Assessing the implications of human land-use change for the transient climate response to cumulative carbon emissions

International Nuclear Information System (INIS)

Simmons, C T; Matthews, H D

2016-01-01

Recent research has shown evidence of a linear climate response to cumulative CO 2 emissions, which implies that the source, timing, and amount of emissions does not significantly influence the climate response per unit emission. Furthermore, these analyses have generally assumed that the climate response to land-use CO 2 emissions is equivalent to that of fossil fuels under the assumption that, once in the atmosphere, the radiative forcing induced by CO 2 is not sensitive to the emissions source. However, land-cover change also affects surface albedo and the strength of terrestrial carbon sinks, both of which have an additional climate effect. In this study, we use a coupled climate-carbon cycle model to assess the climate response to historical and future cumulative land-use CO 2 emissions, in order to compare it to the response to fossil fuel CO 2 . We find that when we isolate the CO 2 -induced (biogeochemical) temperature changes associated with land-use change, then the climate response to cumulative land-use emissions is equivalent to that of fossil fuel CO 2 . We show further that the globally-averaged albedo-induced biophysical cooling from land-use change is non-negligible and may be of comparable magnitude to the biogeochemical warming, with the result that the net climate response to land-use change is substantially different from a linear response to cumulative emissions. However, our new simulations suggest that the biophysical cooling from land-use change follows its own independent (negative) linear response to cumulative net land-use CO 2 emissions, which may provide a useful scaling factor for certain applications when evaluating the full transient climate response to emissions. (letter)

Integrated assessment of climate change with reductions of methane emissions

NARCIS (Netherlands)

Amstel, van A.R.

2005-01-01

We have been living in the anthropocene era since about 1950, and evidence of human influence on the natural ecosystems and climate is mounting. Reductions of greenhouse gas emissions are needed to reduce the effects of climate change in the future. In an integrated assessment with the IMAGE model

The Implications of Intermediate Stop Operations on Aviation Emissions and Climate

Directory of Open Access Journals (Sweden)

Florian Linke

2017-12-01

Full Text Available Among the various transport modes aviation's impact on climate change deserves special attention. Due to typical flight altitudes in the upper troposphere and above, the effect of aircraft engine emissions like e.g. water vapour, nitrogen oxides and aerosols on radiative forcing agents is substantial. The projected doubling of aircraft movements in the next 15 years will lead to an increase of aviation's impact on climate and requires immediate mitigation options. Besides technological measures also new operational strategies are widely discussed; one of these concepts which has been subject of several studies in the past is Intermediate Stop Operations (ISO. It is based on the idea to reduce the stage length of flights by performing one or more intermediate landings during a mission. Here, we analyse the ISO concept by combining different models, which include a realistic traffic simulation taking into account operational constraints and ambient conditions, like e.g. wind, the calculation of engine emissions and the integration of a climate response model. We analyse the ISO concept for today's worldwide aircraft fleet, including its influence on global emissions distributions as well as the impact on climate change by taking into account CO2 and non-CO2 effects, arising from contrail-cirrus, water vapour and nitrogen oxide emissions. We show in agreement with earlier findings that due to shorter flight distances the amount of fuel burnt over the mission can be reduced by roughly 5 % on average globally. For the first time, we quantify the climate impact of ISO, where the flight trajectory is optimised for fuel use and the aircraft is not redesigned for the ISO procedure. We find an increased warming effect, which arises from nitrogen oxide and water vapour emissions, which are released at higher cruise altitudes and which over-compensate reduced warming effects from CO2 and contrail-cirrus. However, we expect a climate impact reduction for

Zero emission targets as long-term global goals for climate protection

International Nuclear Information System (INIS)

Rogelj, Joeri; Riahi, Keywan; Schaeffer, Michiel; Hare, William; Meinshausen, Malte; Knutti, Reto; Alcamo, Joseph

2015-01-01

Recently, assessments have robustly linked stabilization of global-mean temperature rise to the necessity of limiting the total amount of emitted carbon-dioxide (CO 2 ). Halting global warming thus requires virtually zero annual CO 2 emissions at some point. Policymakers have now incorporated this concept in the negotiating text for a new global climate agreement, but confusion remains about concepts like carbon neutrality, climate neutrality, full decarbonization, and net zero carbon or net zero greenhouse gas (GHG) emissions. Here we clarify these concepts, discuss their appropriateness to serve as a long-term global benchmark for achieving temperature targets, and provide a detailed quantification. We find that with current pledges and for a likely (>66%) chance of staying below 2 °C, the scenario literature suggests net zero CO 2 emissions between 2060 and 2070, with net negative CO 2 emissions thereafter. Because of residual non-CO 2 emissions, net zero is always reached later for total GHG emissions than for CO 2 . Net zero emissions targets are a useful focal point for policy, linking a global temperature target and socio-economic pathways to a necessary long-term limit on cumulative CO 2 emissions. (letter)

The response of the climate system to very high greenhouse gas emission scenarios

International Nuclear Information System (INIS)

Sanderson, Benjamin M; O'Neill, Brian C; Kiehl, Jeffrey T; Meehl, Gerald A; Knutti, Reto; Washington, Warren M

2011-01-01

Well informed decisions on climate policy necessitate simulation of the climate system for a sufficiently wide range of emissions scenarios. While recent literature has been devoted to low emissions futures, the potential for very high emissions has not been thoroughly explored. We specify two illustrative emissions scenarios that are significantly higher than the A1FI scenario, the highest scenario considered in past IPCC reports, and simulate them in a global climate model to investigate their climate change implications. Relative to the A1FI scenario, our highest scenario results in an additional 2 K of global mean warming above A1FI levels by 2100, a complete loss of arctic summer sea-ice by 2070 and an additional 43% sea level rise due to thermal expansion above A1FI levels by 2100. Regional maximum temperature increases from late 20th century values are 50-100% greater than A1FI increases, with some regions such as the Central US, the Tibetan plateau and Alaska showing a 300-400% increase above A1FI levels.

The response of the climate system to very high greenhouse gas emission scenarios

Energy Technology Data Exchange (ETDEWEB)

Sanderson, Benjamin M; O' Neill, Brian C; Kiehl, Jeffrey T; Meehl, Gerald A [National Center for Atmospheric Research, Boulder, CO (United States); Knutti, Reto; Washington, Warren M, E-mail: bsander@ucar.edu [Institute for Atmospheric and Climate Science, ETH Zurich (Switzerland)

2011-07-15

Well informed decisions on climate policy necessitate simulation of the climate system for a sufficiently wide range of emissions scenarios. While recent literature has been devoted to low emissions futures, the potential for very high emissions has not been thoroughly explored. We specify two illustrative emissions scenarios that are significantly higher than the A1FI scenario, the highest scenario considered in past IPCC reports, and simulate them in a global climate model to investigate their climate change implications. Relative to the A1FI scenario, our highest scenario results in an additional 2 K of global mean warming above A1FI levels by 2100, a complete loss of arctic summer sea-ice by 2070 and an additional 43% sea level rise due to thermal expansion above A1FI levels by 2100. Regional maximum temperature increases from late 20th century values are 50-100% greater than A1FI increases, with some regions such as the Central US, the Tibetan plateau and Alaska showing a 300-400% increase above A1FI levels.

Climate-driven effects of fire on winter habitat for caribou in the Alaskan-Yukon Arctic

Science.gov (United States)

Gustine, David D.; Brinkman, Todd J.; Lindgren, Michael A.; Schmidt, Jennifer I.; Rupp, T. Scott; Adams, Layne G.

2014-01-01

Climatic warming has direct implications for fire-dominated disturbance patterns in northern ecosystems. A transforming wildfire regime is altering plant composition and successional patterns, thus affecting the distribution and potentially the abundance of large herbivores. Caribou (Rangifer tarandus) are an important subsistence resource for communities throughout the north and a species that depends on terrestrial lichen in late-successional forests and tundra systems. Projected increases in area burned and reductions in stand ages may reduce lichen availability within caribou winter ranges. Sufficient reductions in lichen abundance could alter the capacity of these areas to support caribou populations. To assess the potential role of a changing fire regime on winter habitat for caribou, we used a simulation modeling platform, two global circulation models (GCMs), and a moderate emissions scenario to project annual fire characteristics and the resulting abundance of lichen-producing vegetation types (i.e., spruce forests and tundra >60 years old) across a modeling domain that encompassed the winter ranges of the Central Arctic and Porcupine caribou herds in the Alaskan-Yukon Arctic. Fires were less numerous and smaller in tundra compared to spruce habitats throughout the 90-year projection for both GCMs. Given the more likely climate trajectory, we projected that the Porcupine caribou herd, which winters primarily in the boreal forest, could be expected to experience a greater reduction in lichen-producing winter habitats (−21%) than the Central Arctic herd that wintered primarily in the arctic tundra (−11%). Our results suggest that caribou herds wintering in boreal forest will undergo fire-driven reductions in lichen-producing habitats that will, at a minimum, alter their distribution. Range shifts of caribou resulting from fire-driven changes to winter habitat may diminish access to caribou for rural communities that reside in fire-prone areas.

Climate-driven effects of fire on winter habitat for caribou in the Alaskan-Yukon Arctic.

Directory of Open Access Journals (Sweden)

David D Gustine

Full Text Available Climatic warming has direct implications for fire-dominated disturbance patterns in northern ecosystems. A transforming wildfire regime is altering plant composition and successional patterns, thus affecting the distribution and potentially the abundance of large herbivores. Caribou (Rangifer tarandus are an important subsistence resource for communities throughout the north and a species that depends on terrestrial lichen in late-successional forests and tundra systems. Projected increases in area burned and reductions in stand ages may reduce lichen availability within caribou winter ranges. Sufficient reductions in lichen abundance could alter the capacity of these areas to support caribou populations. To assess the potential role of a changing fire regime on winter habitat for caribou, we used a simulation modeling platform, two global circulation models (GCMs, and a moderate emissions scenario to project annual fire characteristics and the resulting abundance of lichen-producing vegetation types (i.e., spruce forests and tundra >60 years old across a modeling domain that encompassed the winter ranges of the Central Arctic and Porcupine caribou herds in the Alaskan-Yukon Arctic. Fires were less numerous and smaller in tundra compared to spruce habitats throughout the 90-year projection for both GCMs. Given the more likely climate trajectory, we projected that the Porcupine caribou herd, which winters primarily in the boreal forest, could be expected to experience a greater reduction in lichen-producing winter habitats (-21% than the Central Arctic herd that wintered primarily in the arctic tundra (-11%. Our results suggest that caribou herds wintering in boreal forest will undergo fire-driven reductions in lichen-producing habitats that will, at a minimum, alter their distribution. Range shifts of caribou resulting from fire-driven changes to winter habitat may diminish access to caribou for rural communities that reside in fire-prone areas.

Climate-driven effects of fire on winter habitat for caribou in the Alaskan-Yukon Arctic.

Science.gov (United States)

Gustine, David D; Brinkman, Todd J; Lindgren, Michael A; Schmidt, Jennifer I; Rupp, T Scott; Adams, Layne G

2014-01-01

Climatic warming has direct implications for fire-dominated disturbance patterns in northern ecosystems. A transforming wildfire regime is altering plant composition and successional patterns, thus affecting the distribution and potentially the abundance of large herbivores. Caribou (Rangifer tarandus) are an important subsistence resource for communities throughout the north and a species that depends on terrestrial lichen in late-successional forests and tundra systems. Projected increases in area burned and reductions in stand ages may reduce lichen availability within caribou winter ranges. Sufficient reductions in lichen abundance could alter the capacity of these areas to support caribou populations. To assess the potential role of a changing fire regime on winter habitat for caribou, we used a simulation modeling platform, two global circulation models (GCMs), and a moderate emissions scenario to project annual fire characteristics and the resulting abundance of lichen-producing vegetation types (i.e., spruce forests and tundra >60 years old) across a modeling domain that encompassed the winter ranges of the Central Arctic and Porcupine caribou herds in the Alaskan-Yukon Arctic. Fires were less numerous and smaller in tundra compared to spruce habitats throughout the 90-year projection for both GCMs. Given the more likely climate trajectory, we projected that the Porcupine caribou herd, which winters primarily in the boreal forest, could be expected to experience a greater reduction in lichen-producing winter habitats (-21%) than the Central Arctic herd that wintered primarily in the arctic tundra (-11%). Our results suggest that caribou herds wintering in boreal forest will undergo fire-driven reductions in lichen-producing habitats that will, at a minimum, alter their distribution. Range shifts of caribou resulting from fire-driven changes to winter habitat may diminish access to caribou for rural communities that reside in fire-prone areas.

Response of climate to regional emissions of ozone precursors: sensitivities and warming potentials

International Nuclear Information System (INIS)

Berntsen, T.K.; Fuglestvedt, J.S.; Joshi, M.M.; Shine, K.P.; Hauglustaine, D.A.; Li, L.

2005-01-01

The response of climate to ozone perturbations caused by regional emissions of NO x or CO has been studied through a sequence of model simulations. Changes C and OH concentrations due to emission perturbations in Europe and southeast Asia have been calculated with two global 3-D chemical tracer models(CTMs; LMDzINCA and Oslo-CTM2). The radiative transfer codes of three general circulation models (GCMs; ECHAM4, UREAD and LMD) have been used to calculate the radiative forcing of the O 3 perturbations, and for a subset of the cases full GCM simulations have been performed with ECHAM4 and UREAD. The results have been aggregated to a global number in two ways: first, through integrating the global-mean radiative forcing of a sustained step change in emissions, and second through a modified concept (SGWP*) which includes possible differences in the climate sensitivity of O 3 , CH 4 and CO 2 changes. In terms of change in global tropospheric O 3 burden the two CTMs differ by less than 30%. Both CTMs show a higher north/south gradient in the sensitivity to changes in NO x emission than for CO. We are not able to conclude whether real O 3 perturbations in general have a different climate sensitivity from CO 2 . However, in both GCMs high-latitude emission perturbations lead to climate perturbations with higher (10-30%) climate sensitivities. The calculated SGWP*, for a 100 yr time horizon, are negative for three of the four CTM/GCM combinations for European emissions (-9.6 to +6.9), while for the Asian emissions the SGWP* (H=100) is always positive (+2.9 to +25) indicating a warming. For CO the SGWP* values (3.8 and 4.4 for European and Asian emissions respectively, with only the Oslo-CTM2/ECHAM4 model combination) are less regionally dependent. Our results support the view that for NO x , regionally different weighting factors for the emissions are necessary. For CO the results are more robust and one global number may be acceptable

Trading off Aircraft Fuel Burn and NO x Emissions for Optimal Climate Policy.

Science.gov (United States)

Freeman, Sarah; Lee, David S; Lim, Ling L; Skowron, Agnieszka; De León, Ruben Rodriguez

2018-03-06

Aviation emits pollutants that affect the climate, including CO 2 and NO x , NO x indirectly so, through the formation of tropospheric ozone and reduction of ambient methane. To improve the fuel performance of engines, combustor temperatures and pressures often increase, increasing NO x emissions. Conversely, combustor modifications to reduce NO x may increase CO 2 . Hence, a technology trade-off exists, which also translates to a trade-off between short-lived climate forcers and a long-lived greenhouse gas, CO 2 . Moreover, the NO x -O 3 -CH 4 system responds in a nonlinear manner, according to both aviation emissions and background NO x . A simple climate model was modified to incorporate nonlinearities parametrized from a complex chemistry model. Case studies showed that for a scenario of a 20% reduction in NO x emissions the consequential CO 2 penalty of 2% actually increased the total radiative forcing (RF). For a 2% fuel penalty, NO x emissions needed to be reduced by >43% to realize an overall benefit. Conversely, to ensure that the fuel penalty for a 20% NO x emission reduction did not increase overall forcing, a 0.5% increase in CO 2 was found to be the "break even" point. The time scales of the climate effects of NO x and CO 2 are quite different, necessitating careful analysis of proposed emissions trade-offs.

Proposal for new climate agreements: Economic growth determines the emission quota

International Nuclear Information System (INIS)

Kallbekken, Steffen; Tjernshaugen, Andreas

2002-01-01

Long-term obligations to curb the emission of climate gases involve economic uncertainty because it is difficult to determine the cost of future reductions. This may be the principle reason why the USA and the developing countries are reluctant to accept binding demands on their emissions of climate gases. For example, the commitments of the Kyoto Protocol were agreed upon more than ten years before they shall be put to force. Over such a long time span it is impossible to predict the development of the economy as well as the gas emissions. Usually economical development leads to increased gas emission. If a country commits itself to a quantified limit on its emission, and the economical development turns out to be much faster than predicted, then living up to the commitments may be very expensive. The same is true if the economic growth occurs in the polluting sectors to a larger degree than expected. Many heads of state thus fear that binding emission targets may restrain economic growth

The energy-climate challenge: Recent trends in CO2 emissions from fuel combustion

International Nuclear Information System (INIS)

Quadrelli, Roberta; Peterson, Sierra

2007-01-01

Fossil fuel combustion is the single largest human influence on climate, accounting for 80% of anthropogenic greenhouse gas emissions. This paper presents trends in world carbon dioxide (CO 2 ) emissions from fossil fuel combustion worldwide, based on the estimates of the International Energy Agency (IEA) [IEA, 2006a. CO 2 Emissions from Fuel Combustion 1971-2004. International Energy Agency, Paris, France]. Analyzing the drivers of CO 2 emissions, the paper considers regions, types of fuel, sectors, and socio-economic indicators. The paper then examines the growing body of climate change mitigation policies and measures, both multinational and federal. Policies discussed include the Kyoto Protocol, the European Union Emissions Trading Scheme, and the potential measures to be implemented in 2012 and beyond. CO 2 emissions of recent years have grown at the highest rates ever recorded, an observed trend incompatible with stabilizing atmospheric concentrations of greenhouse gases and avoiding long-term climate change. Within this aggregate upward trend, a comparison of emissions sources proves dynamic: while industrialized countries have so far dominated historical emissions, rapid growth in energy demand of developing economies, led by China, may soon spur their absolute emissions beyond those of industrialized countries. To provide context for the drivers of CO 2 emissions, the paper examines fuel sources, from coal to biofuels, and fuel use in the production of heat and electricity, in transport, in industrial production and in households. The sectoral analysis illustrates the primacy, in terms of emissions growth and absolute emissions, of two sectors: electricity and heat generation, and transport. A discussion of several socio-economic emissions drivers complements the paper's analysis of mitigation mechanisms. As illustrated, emissions per capita and emissions per unit of economic production, as measured in gross domestic product (GDP), vary widely between

Climate, energy and emissions trading in the EU and DK

International Nuclear Information System (INIS)

Dyck-Madsen, S.

2004-04-01

European Union member states are facing two serious challenges: human-induced climatic changes and oil shortage. Evidence that human-induced global heating is threatening the climatic balance is piling up and the conflicts over the last oil resources are becoming critical. The European Union has neither large oil resources nor foreign-political or military power to conquer additional oil resources. The EU Commission's awareness of these facts is influencing the EU energy and climate policy. Recently EU launched the directive on carbon dioxide emissions trading within certain energy-heavy sectors. The greenhouse gas emission allowance trading directive requires a national ceiling on the allocation of CO 2 quotas for the heavy industry and energy sectors, thus adapting the quantity of quotas to the Kyoto requirements. This requirement can be quite extensive for the sectors affected by the greenhouse gas emission allowance trading directive, if national governments choose to abstain from political intervention in order to reduce release of greenhouse gases in sectors outside the emissions trading, e.g. agriculture, transportation, households, and smaller industry and service. Lack of action in these sectors will require the governments to impose either large burdens or use of national Joint Implementation and Clean Development agreements on the heavy industry and energy sectors outside national borders, thus conflicting with the Kyoto Protocol. (BA)

Climate variability and trends in biogenic emissions imprinted on satellite observations of formaldehyde from SCIAMACHY and OMI sounders

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Stavrakou, Trissevgeni; Müller, Jean-François; Bauwens, Maite; De Smedt, Isabelle; Van Roozendael, Michel

2017-04-01

Biogenic hydrocarbon emissions (BVOC) respond to temperature, photosynthetically active radiation, leaf area index, as well as to factors like leaf age, soil moisture, and ambient CO2 concentrations. Isoprene is the principal contributor to BVOC emissions and accounts for about half of the estimated total emissions on the global scale, whereas monoterpenes are also significant over boreal ecosystems. Due to their large emissions, their major role in the tropospheric ozone formation and contribution to secondary organic aerosols, BVOCs are highly relevant to both air quality and climate. Their oxidation in the atmosphere leads to the formation of formaldehyde (HCHO) at high yields. Satellite observations of HCHO abundances can therefore inform us on the spatial and temporal variability of the underlying sources and on their emission trends. The main objective of this study is to investigate the interannual variability and trends of observed HCHO columns during the growing season, when BVOC emissions are dominant, and interpret them in terms of BVOC emission flux variability. To this aim, we use the MEGAN-MOHYCAN model driven by the ECMWF ERA-interim meteorology to calculate bottom-up BVOC fluxes on the global scale (Müller et al. 2008, Stavrakou et al. 2014) over 2003-2015, and satellite HCHO observations from SCIAMACHY (2003-2011) and OMI (2005-2015) instruments (De Smedt et al. 2008, 2015). We focus on mid- and high-latitude regions of the Northern Hemisphere in summertime, as well as tropical regions taking care to exclude biomass burning events which also lead to HCHO column enhancements. We find generally a very strong temporal correlation (>0.7) between the simulated BVOC emissions and the observed HCHO columns over temperate and boreal ecosystems. Positive BVOC emission trends associated to warming climate are found in almost all regions and are well corroborated by the observations. Furthermore, using OMI HCHO observations over 2005-2015 as constraints in

Separating the Effects of Tropical Atlantic and Pacific SST-driven Climate Variability on Amazon Carbon Exchange

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Liptak, J.; Keppel-Aleks, G.

2016-12-01

Amazon forests store an estimated 25% percent of global terrestrial carbon per year1, 2, but the responses of Amazon carbon uptake to climate change is highly uncertain. One source of this uncertainty is tropical sea surface temperature variability driven by teleconnections. El Nino-Southern Oscillation (ENSO) is a key driver of year-to-year Amazon carbon exchange, with associated temperature and precipitation changes favoring net carbon storage in La Nina years, and net carbon release during El Nino years3. To determine how Amazon climate and terrestrial carbon fluxes react to ENSO alone and in concert with other SST-driven teleconnections such as the Atlantic Multidecadal Oscillation (AMO), we force the atmosphere (CAM5) and land (CLM4) components of the CESM(BGC) with prescribed monthly SSTs over the period 1950—2014 in a Historical control simulation. We then run an experiment (PAC) with time-varying SSTs applied only to the tropical equatorial Pacific Ocean, and repeating SST seasonal cycle climatologies elsewhere. Limiting SST variability to the equatorial Pacific indicates that other processes enhance ENSO-driven Amazon climate anomalies. Compared to the Historical control simulation, warming, drying and terrestrial carbon loss over the Amazon during El Nino periods are lower in the PAC simulation, especially prior to 1990 during the cool phase of the AMO. Cooling, moistening, and net carbon uptake during La Nina periods are also reduced in the PAC simulation, but differences are greater after 1990 during the warm phase of the AMO. By quantifying the relationships among climate drivers and carbon fluxes in the Historical and PAC simulations, we both assess the sensitivity of these relationships to the magnitude of ENSO forcing and quantify how other teleconnections affect ENSO-driven Amazon climate feedbacks. We expect that these results will help us improve hypotheses for how Atlantic and Pacific climate trends will affect future Amazon carbon carbon

On the efficiency gains of emissions trading when climate deals are non-cooperative

Energy Technology Data Exchange (ETDEWEB)

Godal, Odd; Holtsmark, Bjart

2011-07-15

This paper studies, in a numerical environment, climate treaties with emissions trading when national quotas result from strategic individual choice. We find that the larger the number of parties to the deal, the smaller are the emissions reductions and the lower the welfare. If insisting on stability with respect to participation, climate treaties involve few parties and yield practically no emissions reductions. While these results contrast with some optimistic studies, our numerical example conforms established results if modelling the problem in the more traditional sense. (Author)

Recent climatic change, greenhouse gas emissions and future climate: The implications for India

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Rao, P. Govinda; Kelly, P. M.; Hulme, M.

1996-03-01

In this paper, we discuss past climatic trends over India, greenhouse gas emissions due to energy consumption, forest and land-use changes, climate change scenarios for the year 2050, potential consequences for agriculture and cyclone activity and the possibility that India might limit the increasing trend in its emissions. India's mean surface air temperature has increased significantly by about 0.4°C over the past ccntury. Neither monsoon nor annual rainfall shows any significant trend. On average, there has been a rise in sea levels around India over recent decades, though considerable uncertainties exist in the accuracy and interpretation of the available data. Carbon emissions from the energy sector amount to 71 MT a year, equivalent to all other sectors combined. From land-use data, a marginal net sequestration of 5.25 million tonnes of carbon occurred during 1986. Following the IPCC guidelines, methane emissions from rice and livestock are estimated at 17.4 and 12.8 Tg/year, respectively. According to recent climate model projections, India may experience a further rise in temperature of 1 °C by the year 2050, about four times the rate of warming experienced over the past 100 years. A modest increase in precipitation amounts might occur. Cereals production is estimated to decrease and the nutrition security of the population-rich but land-hungry region of India might be hampered. An increase in local tropical cyclone activity may occur over thc next century, posing added problems as large areas in the coastal regions have a dense population. About 70% of the electricity generation in India is from coal-based power stations. Altering this dependence significantly to reduce emissions would imply a substantial change in the present energy policy of India. There is great potential for improving energy efficiency and conservation. The adoption of cleaner coal-technologies should be considered, as must the development of renewable, non-conventional energy

Modelling the influence of changing climate in present and future marine eutrophication impacts from spring barley production

DEFF Research Database (Denmark)

Cosme, Nuno Miguel Dias; Niero, Monia

2017-01-01

Nitrate concentration and runoff are site-specific and driven by climatic factors and crop management. As such, nitrate emissions may increase in the future due to climate change, affecting the marine eutrophication mechanism. In this context, and considering the case of spring barley production...... of different normalisation references when comparing future Life Cycle Assessment (LCA) scenarios with current production systems. A parameterised characterisation model was developed to gauge the influence of future climatic-driven pressures on the marine eutrophication impact pathway. Spatial differentiation...

Functional Resilience against Climate-Driven Extinctions - Comparing the Functional Diversity of European and North American Tree Floras.

Directory of Open Access Journals (Sweden)

Mario Liebergesell

Full Text Available Future global change scenarios predict a dramatic loss of biodiversity for many regions in the world, potentially reducing the resistance and resilience of ecosystem functions. Once before, during Plio-Pleistocene glaciations, harsher climatic conditions in Europe as compared to North America led to a more depauperate tree flora. Here we hypothesize that this climate driven species loss has also reduced functional diversity in Europe as compared to North America. We used variation in 26 traits for 154 North American and 66 European tree species and grid-based co-occurrences derived from distribution maps to compare functional diversity patterns of the two continents. First, we identified similar regions with respect to contemporary climate in the temperate zone of North America and Europe. Second, we compared the functional diversity of both continents and for the climatically similar sub-regions using the functional dispersion-index (FDis and the functional richness index (FRic. Third, we accounted in these comparisons for grid-scale differences in species richness, and, fourth, investigated the associated trait spaces using dimensionality reduction. For gymnosperms we find similar functional diversity on both continents, whereas for angiosperms functional diversity is significantly greater in Europe than in North America. These results are consistent across different scales, for climatically similar regions and considering species richness patterns. We decomposed these differences in trait space occupation into differences in functional diversity vs. differences in functional identity. We show that climate-driven species loss on a continental scale might be decoupled from or at least not linearly related to changes in functional diversity. This might be important when analyzing the effects of climate-driven biodiversity change on ecosystem functioning.

Secondary aerosol formation from stress-induced biogenic emissions and possible climate feedbacks

Directory of Open Access Journals (Sweden)

Th. F. Mentel

2013-09-01

Full Text Available Atmospheric aerosols impact climate by scattering and absorbing solar radiation and by acting as ice and cloud condensation nuclei. Biogenic secondary organic aerosols (BSOAs comprise an important component of atmospheric aerosols. Biogenic volatile organic compounds (BVOCs emitted by vegetation are the source of BSOAs. Pathogens and insect attacks, heat waves and droughts can induce stress to plants that may impact their BVOC emissions, and hence the yield and type of formed BSOAs, and possibly their climatic effects. This raises questions of whether stress-induced changes in BSOA formation may attenuate or amplify effects of climate change. In this study we assess the potential impact of stress-induced BVOC emissions on BSOA formation for tree species typical for mixed deciduous and Boreal Eurasian forests. We studied the photochemical BSOA formation for plants infested by aphids in a laboratory setup under well-controlled conditions and applied in addition heat and drought stress. The results indicate that stress conditions substantially modify BSOA formation and yield. Stress-induced emissions of sesquiterpenes, methyl salicylate, and C17-BVOCs increase BSOA yields. Mixtures including these compounds exhibit BSOA yields between 17 and 33%, significantly higher than mixtures containing mainly monoterpenes (4–6% yield. Green leaf volatiles suppress SOA formation, presumably by scavenging OH, similar to isoprene. By classifying emission types, stressors and BSOA formation potential, we discuss possible climatic feedbacks regarding aerosol effects. We conclude that stress situations for plants due to climate change should be considered in climate–vegetation feedback mechanisms.

Avoided emissions. Enterprises assess their solutions for the climate

International Nuclear Information System (INIS)

Colas, Julien

2017-09-01

In its first part, this publication gives an overview of the issues of avoided emissions: reasons for their calculation, risks to be understood and anticipated, relationships between avoided emissions and enterprises, avoided emissions in the enterprise climate strategy, and available calculation methods. The second part describes the methodology and process of calculation of avoided emissions: project initiation, method selection, reference solution selection, scenario elaboration, definition of the scope of calculation, taking the whole value chain into account, result consolidation, communication. A synthesis of recommendations is provided. Within the text, this publication proposes presentations of actions undertaken by several French companies or French subsidiaries like Air France, BASF, EDF, Michelin, Paprec, RTE, Saint-Gobain, SNCF, Suez, Total, Veolia, and others

Transient simulations of historical climate change including interactive carbon emissions from land-use change.

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Matveev, A.; Matthews, H. D.

2009-04-01

Carbon fluxes from land conversion are among the most uncertain variables in our understanding of the contemporary carbon cycle, which limits our ability to estimate both the total human contribution to current climate forcing and the net effect of terrestrial biosphere changes on atmospheric CO2 increases. The current generation of coupled climate-carbon models have made significant progress in simulating the coupled climate and carbon cycle response to anthropogenic CO2 emissions, but do not typically include land-use change as a dynamic component of the simulation. In this work we have incorporated a book-keeping land-use carbon accounting model into the University of Victoria Earth System Climate Model (UVic ESCM), and intermediate-complexity coupled climate-carbon model. The terrestrial component of the UVic ESCM allows an aerial competition of five plant functional types (PFTs) in response to climatic conditions and area availability, and tracks the associated changes in affected carbon pools. In order to model CO2 emissions from land conversion in the terrestrial component of the model, we calculate the allocation of carbon to short and long-lived wood products following specified land-cover change, and use varying decay timescales to estimate CO2 emissions. We use recently available spatial datasets of both crop and pasture distributions to drive a series of transient simulations and estimate the net contribution of human land-use change to historical carbon emissions and climate change.

Climate, duration, and N placement determine N2 O emissions in reduced tillage systems: a meta-analysis.

Science.gov (United States)

van Kessel, Chris; Venterea, Rodney; Six, Johan; Adviento-Borbe, Maria Arlene; Linquist, Bruce; van Groenigen, Kees Jan

2013-01-01

No-tillage and reduced tillage (NT/RT) management practices are being promoted in agroecosystems to reduce erosion, sequester additional soil C and reduce production costs. The impact of NT/RT on N2 O emissions, however, has been variable with both increases and decreases in emissions reported. Herein, we quantitatively synthesize studies on the short- and long-term impact of NT/RT on N2 O emissions in humid and dry climatic zones with emissions expressed on both an area- and crop yield-scaled basis. A meta-analysis was conducted on 239 direct comparisons between conventional tillage (CT) and NT/RT. In contrast to earlier studies, averaged across all comparisons, NT/RT did not alter N2 O emissions compared with CT. However, NT/RT significantly reduced N2 O emissions in experiments >10 years, especially in dry climates. No significant correlation was found between soil texture and the effect of NT/RT on N2 O emissions. When fertilizer-N was placed at ≥5 cm depth, NT/RT significantly reduced area-scaled N2 O emissions, in particular under humid climatic conditions. Compared to CT under dry climatic conditions, yield-scaled N2 O increased significantly (57%) when NT/RT was implemented <10 years, but decreased significantly (27%) after ≥10 years of NT/RT. There was a significant decrease in yield-scaled N2 O emissions in humid climates when fertilizer-N was placed at ≥5 cm depth. Therefore, in humid climates, deep placement of fertilizer-N is recommended when implementing NT/RT. In addition, NT/RT practices need to be sustained for a prolonged time, particularly in dry climates, to become an effective mitigation strategy for reducing N2 O emissions. © 2012 Blackwell Publishing Ltd.

AC-driven organic light emission devices with carbon nanotubes

Science.gov (United States)

Jeon, So-Yeon; Yu, SeGi

2017-02-01

We have investigated alternating current (AC)-driven organic light-emitting devices (OLEDs), with carbon nanotubes (CNTs) incorporated within the emission layer. With CNT incorporation, the brightness of the OLEDs was substantially improved, and the turn-on voltage was reduced by at least a factor of five. Furthermore, the current levels of the CNT-incorporated OLEDs were lower than that of the reference device. A roughly 70% decrease in the current level was obtained for a CNT concentration of 0.03 wt%. This was accomplished by keeping the concentration of CNTs low and the length of CNTs short, which helped to suppress the percolation networking of CNTs within the emitting layer. Strong local electric fields near the end-tips of CNTs and micro-capacitors formed by dispersed CNTs might have caused this high brightness and these low currents. CNT incorporation in the emitting layer can improve the characteristics of AC-driven OLEDs, which are considered to be one of the candidates for flat panel displays and lightning devices.

AC-driven Organic Light Emission Devices with Carbon Nanotubes

Energy Technology Data Exchange (ETDEWEB)

Jeon, So-Yeon [Sungkyunkwan University, Suwon (Korea, Republic of); Yu, SeGi [Hankuk University of Foreign Studies, Yongin (Korea, Republic of)

2017-02-15

We have investigated alternating current (AC)-driven organic light-emitting devices (OLEDs), with carbon nanotubes (CNTs) incorporated within the emission layer. With CNT incorporation, the brightness of the OLEDs was substantially improved, and the turn-on voltage was reduced by at least a factor of five. Furthermore, the current levels of the CNT-incorporated OLEDs were lower than that of the reference device. A roughly 70% decrease in the current level was obtained for a CNT concentration of 0.03 wt%. This was accomplished by keeping the concentration of CNTs low and the length of CNTs short, which helped to suppress the percolation networking of CNTs within the emitting layer. Strong local electric fields near the end-tips of CNTs and micro-capacitors formed by dispersed CNTs might have caused this high brightness and these low currents. CNT incorporation in the emitting layer can improve the characteristics of AC-driven OLEDs, which are considered to be one of the candidates for flat panel displays and lightning devices.

Impacts of Residential Biofuel Emissions on Air Quality and Climate

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Huang, Y.; Unger, N.; Harper, K.; Storelvmo, T.

2016-12-01

The residential biofuel sector is defined as fuelwood, agricultural residues and dung used for household cooking and heating. Aerosol emissions from this human activity play an important role affecting local, regional and global air quality, climate and public health. However, there are only few studies available that evaluate the net impacts and large uncertainties persist. Here we use the Community Atmosphere Model version 5.3 (CAM v5.3) within the Community Earth System Model version 1.2.2, to quantify the impacts of cook-stove biofuel emissions on air quality and climate. The model incorporates a novel advanced treatment of black carbon (BC) effects on mixed-phase/ice clouds. We update the global anthropogenic emission inventory in CAM v5.3 to a state-of-the-art emission inventory from the Greenhouse Gas-Air Pollution Interactions and Synergies integrated assessment model. Global in-situ and aircraft campaign observations for BC and organic carbon are used to evaluate and validate the model performance. Sensitivity simulations are employed to assess the impacts of residential biofuel emissions on regional and global direct and indirect radiative forcings in the contemporary world. We focus the analyses on several key regions including India, China and Sub-Saharan Africa.

On the data-driven inference of modulatory networks in climate science: an application to West African rainfall

Science.gov (United States)

González, D. L., II; Angus, M. P.; Tetteh, I. K.; Bello, G. A.; Padmanabhan, K.; Pendse, S. V.; Srinivas, S.; Yu, J.; Semazzi, F.; Kumar, V.; Samatova, N. F.

2015-01-01

Decades of hypothesis-driven and/or first-principles research have been applied towards the discovery and explanation of the mechanisms that drive climate phenomena, such as western African Sahel summer rainfall~variability. Although connections between various climate factors have been theorized, not all of the key relationships are fully understood. We propose a data-driven approach to identify candidate players in this climate system, which can help explain underlying mechanisms and/or even suggest new relationships, to facilitate building a more comprehensive and predictive model of the modulatory relationships influencing a climate phenomenon of interest. We applied coupled heterogeneous association rule mining (CHARM), Lasso multivariate regression, and dynamic Bayesian networks to find relationships within a complex system, and explored means with which to obtain a consensus result from the application of such varied methodologies. Using this fusion of approaches, we identified relationships among climate factors that modulate Sahel rainfall. These relationships fall into two categories: well-known associations from prior climate knowledge, such as the relationship with the El Niño-Southern Oscillation (ENSO) and putative links, such as North Atlantic Oscillation, that invite further research.

Climate policy: Bucket or drainer?

International Nuclear Information System (INIS)

Oikonomou, Vlasis; Patel, Martin; Worrell, Ernst

2006-01-01

Worldwide, industry is responsible for about 40% of greenhouse gas (GHG) emissions, making it an important target for climate policy. Energy-intensive industries may be particularly vulnerable to higher energy costs caused by climate policy. If companies cannot offset rising energy costs and would face increased competition from countries without climate policy, they may decide to relocate their industrial production to the countries without climate policy. The resulting net effect of climate policy on GHG emissions in foreign countries is typically referred to as 'carbon leakage'. Carbon leakage may lead to higher global GHG emissions due to the use of less advanced technology in less developed countries. Based on a literature review of climate policy, earlier environmental policy and analyses of historical trends, this paper assesses the carbon leakage effects of climate policy for energy-intensive industries. Reviews of past trends in production location of energy-intensive industries show an increased global production share of Non-Annex 1 countries. However, from empirical analyses we conclude that the trend is primarily driven by regional demand growth. In contrast, climate policy models show a strong carbon leakage. Even though future climate policy may have a more profound impact than environmental policies in the past, the modelling results are doubtful. Leakage generally seems to be overestimated in current models, especially as potential positive spillovers are often not included in the models. The ambiguity of the empirical analyses and the modelling results warrants further research in the importance of production factors for relocation

Impact of preindustrial to present-day changes in short-lived pollutant emissions on atmospheric composition and climate forcing

Science.gov (United States)

Naik, Vaishali; Horowitz, Larry W.; Fiore, Arlene M.; Ginoux, Paul; Mao, Jingqiu; Aghedo, Adetutu M.; Levy, Hiram

2013-07-01

We describe and evaluate atmospheric chemistry in the newly developed Geophysical Fluid Dynamics Laboratory chemistry-climate model (GFDL AM3) and apply it to investigate the net impact of preindustrial (PI) to present (PD) changes in short-lived pollutant emissions (ozone precursors, sulfur dioxide, and carbonaceous aerosols) and methane concentration on atmospheric composition and climate forcing. The inclusion of online troposphere-stratosphere interactions, gas-aerosol chemistry, and aerosol-cloud interactions (including direct and indirect aerosol radiative effects) in AM3 enables a more complete representation of interactions among short-lived species, and thus their net climate impact, than was considered in previous climate assessments. The base AM3 simulation, driven with observed sea surface temperature (SST) and sea ice cover (SIC) over the period 1981-2007, generally reproduces the observed mean magnitude, spatial distribution, and seasonal cycle of tropospheric ozone and carbon monoxide. The global mean aerosol optical depth in our base simulation is within 5% of satellite measurements over the 1982-2006 time period. We conduct a pair of simulations in which only the short-lived pollutant emissions and methane concentrations are changed from PI (1860) to PD (2000) levels (i.e., SST, SIC, greenhouse gases, and ozone-depleting substances are held at PD levels). From the PI to PD, we find that changes in short-lived pollutant emissions and methane have caused the tropospheric ozone burden to increase by 39% and the global burdens of sulfate, black carbon, and organic carbon to increase by factors of 3, 2.4, and 1.4, respectively. Tropospheric hydroxyl concentration decreases by 7%, showing that increases in OH sinks (methane, carbon monoxide, nonmethane volatile organic compounds, and sulfur dioxide) dominate over sources (ozone and nitrogen oxides) in the model. Combined changes in tropospheric ozone and aerosols cause a net negative top

Designing an emissions trading scheme for China: An up-to-date climate policy assessment

OpenAIRE

Hübler, Michael; Löschel, Andreas; Voigt, Sebastian

2014-01-01

We assess recent Chinese climate policy proposals in a multi‐region, multi‐sector computable general equilibrium model with a Chinese carbon emissions trading scheme (ETS). When the emissions intensity per GDP in 2020 is required to be 45% lower than in 2005, the model simulations indicate that the climate policy‐ induced welfare loss in 2020, measured as the level of GDP and welfare in 2020 under climate policy relative to their level under business‐as‐usual (BAU) in the same yea...

EU Action against Climate Change. EU emissions trading. An open scheme promoting global innovation

International Nuclear Information System (INIS)

2005-01-01

The European Union is committed to global efforts to reduce the greenhouse gas emissions from human activities that threaten to cause serious disruption to the world's climate. Building on the innovative mechanisms set up under the Kyoto Protocol to the 1992 United Nations Framework Convention on Climate Change (UNFCCC) - joint implementation, the clean development mechanism and international emissions trading - the EU has developed the largest company-level scheme for trading in emissions of carbon dioxide (CO2), making it the world leader in this emerging market. The emissions trading scheme started in the 25 EU Member States on 1 January 2005

Metrics for aggregating the climate effects of different emissions: a unifying framework

NARCIS (Netherlands)

Tol, R.S.J.; Berntsen, T.K.; O'Neill, B.C.; Fuglestvedt, J.S.; Shine, K.P.

2012-01-01

Multi-gas approaches to climate change policies require a metric establishing equivalences among emissions of various species. Climate scientists and economists have proposed four kinds of such metrics and debated their relative merits. We present a unifying framework that clarifies the

Climate and mortality changes due to reductions in household cooking emissions

Science.gov (United States)

Bergman, Tommi; Mielonen, Tero; Arola, Antti; Kokkola, Harri

2016-04-01

Household cooking is a significant cause for health and environmental problems in the developing countries. There are more than 3 billion people who use biomass for fuel in cooking stoves in their daily life. These cooking stoves use inadequate ventilation and expose especially women and children to indoor smoke. To reduce problems of the biomass burning, India launched an initiative to provide affordable and clean energy solutions for the poorest households by providing clean next-generation cooking stoves. The improved cooking stoves are expected to improve outdoor air quality and to reduce the climate-active pollutants, thus simultaneously slowing the climate change. Previous research has shown that the emissions of black carbon can be decreased substantially, as much as 90 % by applying better technology in cooking stoves. We have implemented reasonable (50% decrease) and best case (90% decrease) scenarios of the reductions in black and organic carbon due to improved cooking stoves in India into ECHAM-HAMMOZ aerosol-climate model. The global simulations of the scenarios will be used to study how the reductions of emissions in India affect the pollutant concentrations and radiation. The simulated reductions in particulate concentrations will also be used to estimate the decrease in mortality rates. Furthermore, we will study how the emission reductions would affect the global climate and mortality if a similar initiative would be applied in other developing countries.

Wildland fire emissions, carbon, and climate: Science overview and knowledge needs

Science.gov (United States)

William T. Sommers; Rachel A. Loehman; Colin C. Hardy

2014-01-01

Wildland fires have influenced the global carbon cycle for 420 million years of Earth history, interacting with climate to define vegetation characteristics and distributions, trigger abrupt ecosystem shifts, and move carbon among terrestrial and atmospheric pools. Carbon dioxide (CO2) is the dominant driver of ongoing climate change and the principal emissions...

Cathode fall model and current-voltage characteristics of field emission driven direct current microplasmas

Energy Technology Data Exchange (ETDEWEB)

Venkattraman, Ayyaswamy [Department of Applied Mechanics, Indian Institute of Technology Madras, Chennai 600036 (India)

2013-11-15

The post-breakdown characteristics of field emission driven microplasma are studied theoretically and numerically. A cathode fall model assuming a linearly varying electric field is used to obtain equations governing the operation of steady state field emission driven microplasmas. The results obtained from the model by solving these equations are compared with particle-in-cell with Monte Carlo collisions simulation results for parameters including the plasma potential, cathode fall thickness, ion number density in the cathode fall, and current density vs voltage curves. The model shows good overall agreement with the simulations but results in slightly overpredicted values for the plasma potential and the cathode fall thickness attributed to the assumed electric field profile. The current density vs voltage curves obtained show an arc region characterized by negative slope as well as an abnormal glow discharge characterized by a positive slope in gaps as small as 10 μm operating at atmospheric pressure. The model also retrieves the traditional macroscale current vs voltage theory in the absence of field emission.

Cathode fall model and current-voltage characteristics of field emission driven direct current microplasmas

International Nuclear Information System (INIS)

Venkattraman, Ayyaswamy

2013-01-01

The post-breakdown characteristics of field emission driven microplasma are studied theoretically and numerically. A cathode fall model assuming a linearly varying electric field is used to obtain equations governing the operation of steady state field emission driven microplasmas. The results obtained from the model by solving these equations are compared with particle-in-cell with Monte Carlo collisions simulation results for parameters including the plasma potential, cathode fall thickness, ion number density in the cathode fall, and current density vs voltage curves. The model shows good overall agreement with the simulations but results in slightly overpredicted values for the plasma potential and the cathode fall thickness attributed to the assumed electric field profile. The current density vs voltage curves obtained show an arc region characterized by negative slope as well as an abnormal glow discharge characterized by a positive slope in gaps as small as 10 μm operating at atmospheric pressure. The model also retrieves the traditional macroscale current vs voltage theory in the absence of field emission

Comparing climate and cost impacts of reference levels for reducing emissions from deforestation

Energy Technology Data Exchange (ETDEWEB)

Busch, Jonah [Center for Applied Biodiversity Science, Conservation International, 2011 Crystal Drive, Suite 500, Arlington, VA (United States); Strassburg, Bernardo [Center for Social and Economic Research on the Global Environment, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Cattaneo, Andrea [Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540-1644 (United States); Lubowski, Ruben [Environmental Defense Fund, 1875 Connecticut Avenue NW, Washington, DC (United States); Bruner, Aaron; Rice, Richard; Boltz, Frederick [Conservation International, 2011 Crystal Drive, Suite 500, Arlington, VA (United States); Creed, Anna; Ashton, Ralph, E-mail: jbusch@conservation.or [Terrestrial Carbon Group, 900 17th Street NW, Suite 700, Washington, DC (United States)

2009-10-15

The climate benefit and economic cost of an international mechanism for reducing emissions from deforestation and degradation (REDD) will depend on the design of reference levels for crediting emission reductions. We compare the impacts of six proposed reference level designs on emission reduction levels and on cost per emission reduction using a stylized partial equilibrium model (the open source impacts of REDD incentives spreadsheet; OSIRIS). The model explicitly incorporates national incentives to participate in an international REDD mechanism as well as international leakage of deforestation emissions. Our results show that a REDD mechanism can provide cost-efficient climate change mitigation benefits under a broad range of reference level designs. We find that the most effective reference level designs balance incentives to reduce historically high deforestation emissions with incentives to maintain historically low deforestation emissions. Estimates of emission reductions under REDD depend critically on the degree to which demand for tropical frontier agriculture generates leakage. This underscores the potential importance to REDD of complementary strategies to supply agricultural needs outside of the forest frontier.

Comparing climate and cost impacts of reference levels for reducing emissions from deforestation

International Nuclear Information System (INIS)

Busch, Jonah; Strassburg, Bernardo; Cattaneo, Andrea; Lubowski, Ruben; Bruner, Aaron; Rice, Richard; Boltz, Frederick; Creed, Anna; Ashton, Ralph

2009-01-01

The climate benefit and economic cost of an international mechanism for reducing emissions from deforestation and degradation (REDD) will depend on the design of reference levels for crediting emission reductions. We compare the impacts of six proposed reference level designs on emission reduction levels and on cost per emission reduction using a stylized partial equilibrium model (the open source impacts of REDD incentives spreadsheet; OSIRIS). The model explicitly incorporates national incentives to participate in an international REDD mechanism as well as international leakage of deforestation emissions. Our results show that a REDD mechanism can provide cost-efficient climate change mitigation benefits under a broad range of reference level designs. We find that the most effective reference level designs balance incentives to reduce historically high deforestation emissions with incentives to maintain historically low deforestation emissions. Estimates of emission reductions under REDD depend critically on the degree to which demand for tropical frontier agriculture generates leakage. This underscores the potential importance to REDD of complementary strategies to supply agricultural needs outside of the forest frontier.

Global terrestrial isoprene emission models: sensitivity to variability in climate and vegetation

Directory of Open Access Journals (Sweden)

A. Arneth

2011-08-01

Full Text Available Due to its effects on the atmospheric lifetime of methane, the burdens of tropospheric ozone and growth of secondary organic aerosol, isoprene is central among the biogenic compounds that need to be taken into account for assessment of anthropogenic air pollution-climate change interactions. Lack of process-understanding regarding leaf isoprene production as well as of suitable observations to constrain and evaluate regional or global simulation results add large uncertainties to past, present and future emissions estimates. Focusing on contemporary climate conditions, we compare three global isoprene models that differ in their representation of vegetation and isoprene emission algorithm. We specifically aim to investigate the between- and within model variation that is introduced by varying some of the models' main features, and to determine which spatial and/or temporal features are robust between models and different experimental set-ups. In their individual standard configurations, the models broadly agree with respect to the chief isoprene sources and emission seasonality, with maximum monthly emission rates around 20–25 Tg C, when averaged by 30-degree latitudinal bands. They also indicate relatively small (approximately 5 to 10 % around the mean interannual variability of total global emissions. The models are sensitive to changes in one or more of their main model components and drivers (e.g., underlying vegetation fields, climate input which can yield increases or decreases in total annual emissions of cumulatively by more than 30 %. Varying drivers also strongly alters the seasonal emission pattern. The variable response needs to be interpreted in view of the vegetation emission capacities, as well as diverging absolute and regional distribution of light, radiation and temperature, but the direction of the simulated emission changes was not as uniform as anticipated. Our results highlight the need for modellers to evaluate their

Impact of Future Emissions and Climate Change on Surface Ozone over China

Science.gov (United States)

Ma, C. T.; Westervelt, D. M.; Fiore, A. M.; Rieder, H. E.; Kinney, P.; Wang, S.; Correa, G. J. P.

2017-12-01

China's immense ambient air pollution problem and world-leading greenhouse gas emissions place it at the forefront of global efforts to address these related environmental concerns. Here, we analyze the impact of ECLIPSE (Evaluating the Climate and Air Quality Impacts of Short-Lived Pollutants) future emissions scenarios representative of current legislation (CLE) and maximum technically feasible emissions reductions (MFR) on surface ozone (O3) concentrations over China in the 2030s and 2050s, in the context of a changing climate. We use a suite of simulations performed with the NOAA Geophysical Fluid Dynamics Laboratory's AM3 global chemistry-climate model. To estimate the impact of climate change in isolation on Chinese air quality, we hold emissions of air pollutants including O3 precursors fixed at 2015 levels but allow climate (global sea surface temperatures and sea ice cover) to change according to decadal averages for the years 2026-2035 and 2046-2055 from a three-member ensemble of GFDL-CM3 simulations under the RCP8.5 high warming scenario. Evaluation of the present-day simulation (2015 CLE) with observations from 1497 chiefly urban air quality monitoring stations shows that simulated surface O3 is positively biased by 26 ppb on average over the domain of China. Previous studies, however, have shown that the modeled ozone response to changes in NOx emissions over the Eastern United States mirrors the magnitude and structure of observed changes in maximum daily average 8-hour (MDA8) O3 distributions. Therefore, we use the model's simulated changes for the 2030s and 2050s to project changes in policy-relevant MDA8 O3 concentrations. We find an overall increase in MDA8 O3 for CLE scenarios in which emissions of NOx precursors are projected to increase, and under MFR scenarios, an overall decrease, with the highest changes occurring in summertime for both 2030 and 2050 MFR. Under climate change alone, the model simulates a mean summertime decrease of 1.3 ppb

Impact of climate change and climate anomalies on hydrologic and biogeochemical processes in an agricultural catchment of the Chesapeake Bay watershed, USA.

Science.gov (United States)

Wagena, Moges B; Collick, Amy S; Ross, Andrew C; Najjar, Raymond G; Rau, Benjamin; Sommerlot, Andrew R; Fuka, Daniel R; Kleinman, Peter J A; Easton, Zachary M

2018-05-16

Nutrient export from agricultural landscapes is a water quality concern and the cause of mitigation activities worldwide. Climate change impacts hydrology and nutrient cycling by changing soil moisture, stoichiometric nutrient ratios, and soil temperature, potentially complicating mitigation measures. This research quantifies the impact of climate change and climate anomalies on hydrology, nutrient cycling, and greenhouse gas emissions in an agricultural catchment of the Chesapeake Bay watershed. We force a calibrated model with seven downscaled and bias-corrected regional climate models and derived climate anomalies to assess their impact on hydrology and the export of nitrate (NO 3 -), phosphorus (P), and sediment, and emissions of nitrous oxide (N 2 O) and di-nitrogen (N 2 ). Model-average (±standard deviation) results indicate that climate change, through an increase in precipitation and temperature, will result in substantial increases in winter/spring flow (10.6 ± 12.3%), NO 3 - (17.3 ± 6.4%), dissolved P (32.3 ± 18.4%), total P (24.8 ± 16.9%), and sediment (25.2 ± 16.6%) export, and a slight increases in N 2 O (0.3 ± 4.8%) and N 2 (0.2 ± 11.8%) emissions. Conversely, decreases in summer flow (-29.1 ± 24.6%) and the export of dissolved P (-15.5 ± 26.4%), total P (-16.3 ± 20.7%), sediment (-20.7 ± 18.3%), and NO 3 - (-29.1 ± 27.8%) are driven by greater evapotranspiration from increasing summer temperatures. Decreases in N 2 O (-26.9 ± 15.7%) and N 2 (-36.6 ± 22.9%) are predicted in the summer and driven by drier soils. While the changes in flow are related directly to changes in precipitation and temperature, the changes in nutrient and sediment export are, to some extent, driven by changes in agricultural management that climate change induces, such as earlier spring tillage and altered nutrient application timing and by alterations to nutrient cycling in the soil. Copyright © 2018

Climate change impacts on agriculture in 2050 under a range of plausible socioeconomic and emissions scenarios

International Nuclear Information System (INIS)

Wiebe, Keith; Islam, Shahnila; Mason-D’Croz, Daniel; Robertson, Richard; Robinson, Sherman; Lotze-Campen, Hermann; Biewald, Anne; Bodirsky, Benjamin; Müller, Christoph; Popp, Alexander; Sands, Ronald; Tabeau, Andrzej; Van Meijl, Hans; Van der Mensbrugghe, Dominique; Kavallari, Aikaterini; Willenbockel, Dirk

2015-01-01

Previous studies have combined climate, crop and economic models to examine the impact of climate change on agricultural production and food security, but results have varied widely due to differences in models, scenarios and input data. Recent work has examined (and narrowed) these differences through systematic model intercomparison using a high-emissions pathway to highlight the differences. This paper extends that analysis to explore a range of plausible socioeconomic scenarios and emission pathways. Results from multiple climate and economic models are combined to examine the global and regional impacts of climate change on agricultural yields, area, production, consumption, prices and trade for coarse grains, rice, wheat, oilseeds and sugar crops to 2050. We find that climate impacts on global average yields, area, production and consumption are similar across shared socioeconomic pathways (SSP 1, 2 and 3, as we implement them based on population, income and productivity drivers), except when changes in trade policies are included. Impacts on trade and prices are higher for SSP 3 than SSP 2, and higher for SSP 2 than for SSP 1. Climate impacts for all variables are similar across low to moderate emissions pathways (RCP 4.5 and RCP 6.0), but increase for a higher emissions pathway (RCP 8.5). It is important to note that these global averages may hide regional variations. Projected reductions in agricultural yields due to climate change by 2050 are larger for some crops than those estimated for the past half century, but smaller than projected increases to 2050 due to rising demand and intrinsic productivity growth. Results illustrate the sensitivity of climate change impacts to differences in socioeconomic and emissions pathways. Yield impacts increase at high emissions levels and vary with changes in population, income and technology, but are reduced in all cases by endogenous changes in prices and other variables. (paper)

Life cycle ecophysiology of small pelagic fish and climate-driven changes in populations

Science.gov (United States)

Peck, Myron A.; Reglero, Patricia; Takahashi, Motomitsu; Catalán, Ignacio A.

2013-09-01

Due to their population characteristics and trophodynamic role, small pelagic fishes are excellent bio-indicators of climate-driven changes in marine systems world-wide. We argue that making robust projections of future changes in the productivity and distribution of small pelagics will require a cause-and-effect understanding of historical changes based upon physiological principles. Here, we reviewed the ecophysiology of small pelagic (clupeiform) fishes including a matrix of abiotic and biotic extrinsic factors (e.g., temperature, salinity, light, and prey characteristics) and stage-specific vital rates: (1) adult spawning, (2) survival and development of eggs and yolk sac larvae, and (3) feeding and growth of larvae, post-larvae and juveniles. Emphasis was placed on species inhabiting Northwest Pacific and Northeast Atlantic (European) waters for which summary papers are particularly scarce compared to anchovy and sardine in upwelling systems. Our review revealed that thermal niches (optimal and sub-optimal ranges in temperatures) were species- and stage-specific but that temperature effects only partly explained observed changes in the distribution and/or productivity of populations in the Northwest Pacific and Northeast Atlantic; changes in temperature may be necessary but not sufficient to induce population-level shifts. Prey availability during the late larval and early juvenile period was a common, density-dependent mechanism linked to fluctuations in populations but recruitment mechanisms were system-specific suggesting that generalizations of climate drivers across systems should be avoided. We identified gaps in knowledge regarding basic elements of the growth physiology of each life stage that will require additional field and laboratory study. Avenues of research are recommended that will aid the development of models that provide more robust, physiological-based projections of the population dynamics of these and other small pelagic fish. In our

International Experiences and Frameworks to Support Country-Driven Low-Emissions Development

Energy Technology Data Exchange (ETDEWEB)

Benioff, R.; Cochran, J.; Cox, S.

2012-08-01

Countries can use low-emission development strategies (LEDS) to advance sustainable development, promote private-sector growth, and reduce greenhouse gas emissions. This paper proposes a framework -- or support infrastructure -- to enable the efficient exchange of LEDS-related knowledge and technical assistance. Under the proposed framework, countries share LEDS-related resources via coordinating forums, 'knowledge platforms,' and networks of experts and investors. The virtual 'knowledge platforms' foster learning by allowing countries to communicate with each other and share technical reports, data, and analysis tools in support of LEDS development. Investing in all elements of the framework in an integrated fashion increases the efficacy of support for country-driven LEDS.

Measuring a fair and ambitious climate agreement using cumulative emissions

International Nuclear Information System (INIS)

Peters, Glen P; Andrew, Robbie M; Solomon, Susan; Friedlingstein, Pierre

2015-01-01

Policy makers have called for a ‘fair and ambitious’ global climate agreement. Scientific constraints, such as the allowable carbon emissions to avoid exceeding a 2 °C global warming limit with 66% probability, can help define ambitious approaches to climate targets. However, fairly sharing the mitigation challenge to meet a global target involves human values rather than just scientific facts. We develop a framework based on cumulative emissions of carbon dioxide to compare the consistency of countries’ current emission pledges to the ambition of keeping global temperatures below 2 °C, and, further, compare two alternative methods of sharing the remaining emission allowance. We focus on the recent pledges and other official statements of the EU, USA, and China. The EU and US pledges are close to a 2 °C level of ambition only if the remaining emission allowance is distributed based on current emission shares, which is unlikely to be viewed as ‘fair and ambitious’ by others who presently emit less. China’s stated emissions target also differs from measures of global fairness, owing to emissions that continue to grow into the 2020s. We find that, combined, the EU, US, and Chinese pledges leave little room for other countries to emit CO 2 if a 2 °C limit is the objective, essentially requiring all other countries to move towards per capita emissions 7 to 14 times lower than the EU, USA, or China by 2030. We argue that a fair and ambitious agreement for a 2 °C limit that would be globally inclusive and effective in the long term will require stronger mitigation than the goals currently proposed. Given such necessary and unprecedented mitigation and the current lack of availability of some key technologies, we suggest a new diplomatic effort directed at ensuring that the necessary technologies become available in the near future. (letter)

Effect of climate-driven changes in species composition on regional emission capacities of biogenic compounds

Science.gov (United States)

Schurgers, G.; Arneth, A.; Hickler, T.

2011-11-01

Regional or global modeling studies of dynamic vegetation often represent vegetation by large functional units (plant functional types (PFTs)). For simulation of biogenic volatile organic compounds (BVOC) in these models, emission capacities, which give the emission under standardized conditions, are provided as an average value for a PFT. These emission capacities thus hide the known heterogeneity in emission characteristics that are not straightforwardly related to functional characteristics of plants. Here we study the effects of the aggregation of species-level information on emission characteristics at PFT level. The roles of temporal and spatial variability are assessed for Europe by comparing simulations that represent vegetation by dominant tree species on the one hand and by plant functional types on the other. We compare a number of time slices between the Last Glacial Maximum (21,000 years ago) and the present day to quantify the effects of dynamically changing vegetation on BVOC emissions. Spatial heterogeneity of emission factors is studied with present-day simulations. We show that isoprene and monoterpene emissions are of similar magnitude in Europe when the simulation represents dominant European tree species, which indicates that simulations applying typical global-scale emission capacities for PFTs tend to overestimate isoprene and underestimate monoterpene emissions. Moreover, both spatial and temporal variability affect emission capacities considerably, and by aggregating these to PFT level averages, one loses the information on local heterogeneity. Given the reactive nature of these compounds, accounting for spatial and temporal heterogeneity can be important for studies of their fate in the atmosphere.

Reduction emissions from transport sector - EU action against climate change

Science.gov (United States)

2009-08-01

This paper explores and discusses the initiation and development of the EU's policies and strategies against climate change and the share experiences in the EU transport sector to reduce CO2 emission.

Emissions trading in international aviation. Possible design options for an emissions trading scheme and their impact on climate change and the aviation industry

International Nuclear Information System (INIS)

Deuber, Odette; Cames, Martin

2003-01-01

According to the Intergovernmental Panel on Climate Change (IPCC), the contribution of aviation to global warm-ing was 3.5 % in 1992. Considering the average growth rate of 4 % per year, the share might be more than doubled by the end of the first commitment period of the Kyoto Protocol (2012). However, due to difficulties in allocating emissions from international aviation to individual countries, these emissions are exempt from commitments under the Kyoto Protocol, although in Article 2.2 the Parties to the Protocol are obliged to stabilize and reduce greenhouse gas emissions from international aviation. To comply with this obligation, the introduction of emissions trading in international aviation is being discussed within the International Civil Aviation Organisation (ICAO). This paper analyses the design options of such an emissions trading scheme and its impact on climate change and the aviation industry. Among other matters, it discusses issues such as open and closed emissions trading schemes, coverage of gases, initial allocation of allowances and possible caps for the aviation industry. It is based on a re-search project that has been carried out on behalf of the German Federal Environmental Agency. The paper reveals that despite complex tropospheric and stratospheric interactions, as well as allocation problems, there are adequate structural options for the design of an emissions trading scheme. Given an adequate structure, emissions trading offers a great incentive to optimise flight routes not only according to economic but also to climatic factors. Consequently, the system would effectively reduce the contribution of aviation to climate change

Aerosol exposure versus aerosol cooling of climate: what is the optimal emission reduction strategy for human health?

Directory of Open Access Journals (Sweden)

J. Löndahl

2010-10-01

Full Text Available Particles, climate change, and health have thought-provoking interactions. Air pollution is one of the largest environmental problems concerning human health. On the other hand, aerosol particles can have a cooling effect on climate and a reduction of those emissions may result in an increased temperature globally, which in turn may have negative health effects. The objective of this work was to investigate the "total health effects" of aerosol emissions, which include both exposure to particles and consequences for climate change initiated by particles. As a case study the "total health effect" from ship emissions was derived by subtracting the number of deaths caused by exposure with the estimated number of lives saved from the cooling effect of the emissions. The analysis showed that, with current level of scientific understanding, it could not be determined whether ship emissions are negative or positive for human health on a short time scale. This first attempt to approximate the combined effect of particle emissions on health shows that reductions of particulate air pollution will in some cases (black carbon have win-win effects on health and climate, but sometimes also cause a shift from particle exposure-related health effects towards an increasing risk of health consequences from climate change. Thus, measures to reduce aerosol emissions have to be coupled with climate change mitigation actions to achieve a full health benefit on a global level.

Regional aerosol emissions and temperature response: Local and remote climate impacts of regional aerosol forcing

Science.gov (United States)

Lewinschal, Anna; Ekman, Annica; Hansson, Hans-Christen

2017-04-01

Emissions of anthropogenic aerosols vary substantially over the globe and the short atmospheric residence time of aerosols leads to a highly uneven radiative forcing distribution, both spatially and temporally. Regional aerosol radiative forcing can, nevertheless, exert a large influence on the temperature field away from the forcing region through changes in heat transport or the atmospheric or ocean circulation. Moreover, the global temperature response distribution to aerosol forcing may vary depending on the geographical location of the forcing. In other words, the climate sensitivity in one region can vary depending on the location of the forcing. The surface temperature distribution response to changes in sulphate aerosol forcing caused by sulphur dioxide (SO2) emission perturbations in four different regions is investigated using the Norwegian Earth System Model (NorESM). The four regions, Europe, North America, East and South Asia, are all regions with historically high aerosol emissions and are relevant from both an air-quality and climate policy perspective. All emission perturbations are defined relative to the year 2000 emissions provided for the Coupled Model Intercomparison Project phase 5. The global mean temperature change per unit SO2 emission change is similar for all four regions for similar magnitudes of emissions changes. However, the global temperature change per unit SO2 emission in simulations where regional SO2 emission were removed is substantially higher than that obtained in simulations where regional SO2 emissions were increased. Thus, the climate sensitivity to regional SO2 emissions perturbations depends on the magnitude of the emission perturbation in NorESM. On regional scale, on the other hand, the emission perturbations in different geographical locations lead to different regional temperature responses, both locally and in remote regions. The results from the model simulations are used to construct regional temperature potential

Monitoring, reporting and verifying emissions in the climate economy

Science.gov (United States)

Bellassen, Valentin; Stephan, Nicolas; Afriat, Marion; Alberola, Emilie; Barker, Alexandra; Chang, Jean-Pierre; Chiquet, Caspar; Cochran, Ian; Deheza, Mariana; Dimopoulos, Christopher; Foucherot, Claudine; Jacquier, Guillaume; Morel, Romain; Robinson, Roderick; Shishlov, Igor

2015-04-01

The monitoring, reporting and verification (MRV) of greenhouse-gas emissions is the cornerstone of carbon pricing and management mechanisms. Here we consider peer-reviewed articles and 'grey literature' related to existing MRV requirements and their costs. A substantial part of the literature is the regulatory texts of the 15 most important carbon pricing and management mechanisms currently implemented. Based on a comparison of key criteria such as the scope, cost, uncertainty and flexibility of procedures, we conclude that conventional wisdom on MRV is not often promoted in existing carbon pricing mechanisms. Quantification of emissions uncertainty and incentives to reduce this uncertainty are usually only partially applied, if at all. Further, the time and resources spent on small sources of emissions would be expected to be limited. Although provisions aiming at an effort proportionate to the amount of emissions at stake -- 'materiality' -- are widespread, they are largely outweighed by economies of scale: in all schemes, MRV costs per tonne are primarily driven by the size of the source.

Emissions associated with meeting the future global wheat demand: A case study of UK production under climate change constraints

International Nuclear Information System (INIS)

Röder, Mirjam; Thornley, Patricia; Campbell, Grant; Bows-Larkin, Alice

2014-01-01

Highlights: • Conflicts between adapting to climate change, food security and reducing emissions. • Climate change likely to limit wheat production in the southern hemisphere. • Climate change yield benefits marginally increase emissions per unit of product. • Improved yield will result in higher total production emissions. • Production-based inventories discourage an increase in production. - Abstract: Climate change, population growth and socio-structural changes will make meeting future food demands extremely challenging. As wheat is a globally traded food commodity central to the food security of many nations, this paper uses it as an example to explore the impact of climate change on global food supply and quantify the resulting greenhouse gas emissions. Published data on projected wheat production is used to analyse how global production can be increased to match projected demand. The results show that the largest projected wheat demand increases are in areas most likely to suffer severe climate change impacts, but that global demand could be met if northern hemisphere producers exploit climate change benefits to increase production and narrow their yield gaps. Life cycle assessment of different climate change scenarios shows that in the case of one of the most important wheat producers (the UK) it may be possible to improve yields with an increase of only 0.6% in the emission intensity per unit of wheat produced in a 2 °C scenario. However, UK production would need to rise substantially, increasing total UK wheat production emissions by 26%. This demonstrates how national emission inventories and associated targets do not incentivise minimisation of global greenhouse gas emissions while meeting increased food demands, highlighting a triad of challenges: meeting the rising demand for food, adapting to climate change and reducing emissions

Predicting Chronic Climate-Driven Disturbances and Their Mitigation

Energy Technology Data Exchange (ETDEWEB)

McDowell, Nate G.; Michaletz, Sean T.; Bennett, Katrina E.; Solander, Kurt C.; Xu, Chonggang; Maxwell, Reed M.; Middleton, Richard S.

2018-01-01

Society increasingly demands the stable provision of ecosystem resources to support our population. Resource risks from climate-driven disturbances--including drought, heat, insect outbreaks, and wildfire--are rising as a chronic state of disequilibrium results from increasing temperatures and a greater frequency of extreme events. This confluence of increased demand and risk may soon reach critical thresholds. We explain here why extreme chronic disequilibrium of ecosystem function is likely to increase dramatically across the globe, creating no-analog conditions that challenge adaptation. We also present novel mechanistic theory that combines models for disturbance mortality and metabolic scaling to link size-dependent plant mortality to changes in ecosystem stocks and fluxes. Efforts must anticipate and model chronic ecosystem disequilibrium to properly prepare for resilience planning.

Decarbonizing the Global Economy - An Integrated Assessment of Low Carbon Emission Scenarios proposed in Climate Policy

Science.gov (United States)

Hokamp, Sascha; Khabbazan, Mohammad Mohammadi

2017-04-01

In 2015, the Conference of the Parties (COP 21) reaffirmed to targeting the global mean temperature rise below 2 °C in 2100 while finding no consent on decarbonizing the global economy, and instead, the final agreement called for enhanced scientific investigation of low carbon emission scenarios (UNFCC, 2015). In addition, the Climate Action Network International (CAN) proposes Special Reports to address decarbonization and low carbon development including 1.5 °C scenarios (IPCC, 2016). In response to these developments, we investigate whether the carbon emission cuts, in accordance with the recent climate policy proposals, may reach the climate target. To tackle this research question, we employ the coupled climate-energy-economy integrated assessment Model of INvestment and endogenous technological Development (MIND, cf. Edenhofer et al., 2005, Neubersch et al. 2014). Extending MIND's climate module to the two-box version used in the Dynamic Integrated model of Climate and the Economy (DICE, cf. Nordhaus and Sztorc, 2013, Nordhaus 2014), we perform a cost-effectiveness analysis with constraints on anthropogenic carbon emissions. We show that a climate policy scenario with early decarbonization complies with the 2° C climate target, even without Carbon Capturing and Storage (CCS) or negative emissions (see van Vuuren et al., 2013, for negative emissions). However, using emission inertia of 3.7 percent annually, reflecting the inflexibility on transforming the energy sector, we find a climate policy with moderately low emissions from 2100 onwards at a cost in terms of Balanced Growth Equivalents (BGE, cf. Anthoff and Tol, 2009) of 0.764 % that requires an early (2035 vs. 2120) peak of investments in renewable energy production compared to a business-as-usual scenario. Hence, decarbonizing the global economy and achieving the 2 °C target might still be possible before 2100, but the window of opportunity is beginning to close. References: Anthoff, D., and Tol, R

Carbon dioxide emissions and climate change: policy implications for the cement industry

International Nuclear Information System (INIS)

Rehan, R.; Nehdi, M.

2005-01-01

There is growing awareness that the cement industry is a significant contributor to global carbon dioxide (CO 2 ) emissions. It is expected that this industry will come under increasing regulatory pressures to reduce its emissions and contribute more aggressively to mitigating global warming. It is important that the industry's stakeholders become more familiar with greenhouse gas (GHG) emission and associated global warming issues, along with emerging policies that may affect the future of the industry. This paper discusses climate change, the current and proposed actions for mitigating its effects, and the implications of such actions for the cement industry. International negotiations on climate change are summarized and mechanisms available under the Kyoto Protocol for reducing greenhouse gas emissions are explained. The paper examines some of the traditional and emerging policy instruments for greenhouse gas emissions and analyses their merits and drawbacks. The applicability, effectiveness and potential impact of these policy instruments for the global cement industry in general and the Canadian cement industry in particular are discussed with recommendations for possible courses of action

Uncertainty in projected climate change arising from uncertain fossil-fuel emission factors

Science.gov (United States)

Quilcaille, Y.; Gasser, T.; Ciais, P.; Lecocq, F.; Janssens-Maenhout, G.; Mohr, S.

2018-04-01

Emission inventories are widely used by the climate community, but their uncertainties are rarely accounted for. In this study, we evaluate the uncertainty in projected climate change induced by uncertainties in fossil-fuel emissions, accounting for non-CO2 species co-emitted with the combustion of fossil-fuels and their use in industrial processes. Using consistent historical reconstructions and three contrasted future projections of fossil-fuel extraction from Mohr et al we calculate CO2 emissions and their uncertainties stemming from estimates of fuel carbon content, net calorific value and oxidation fraction. Our historical reconstructions of fossil-fuel CO2 emissions are consistent with other inventories in terms of average and range. The uncertainties sum up to a ±15% relative uncertainty in cumulative CO2 emissions by 2300. Uncertainties in the emissions of non-CO2 species associated with the use of fossil fuels are estimated using co-emission ratios varying with time. Using these inputs, we use the compact Earth system model OSCAR v2.2 and a Monte Carlo setup, in order to attribute the uncertainty in projected global surface temperature change (ΔT) to three sources of uncertainty, namely on the Earth system’s response, on fossil-fuel CO2 emission and on non-CO2 co-emissions. Under the three future fuel extraction scenarios, we simulate the median ΔT to be 1.9, 2.7 or 4.0 °C in 2300, with an associated 90% confidence interval of about 65%, 52% and 42%. We show that virtually all of the total uncertainty is attributable to the uncertainty in the future Earth system’s response to the anthropogenic perturbation. We conclude that the uncertainty in emission estimates can be neglected for global temperature projections in the face of the large uncertainty in the Earth system response to the forcing of emissions. We show that this result does not hold for all variables of the climate system, such as the atmospheric partial pressure of CO2 and the

Global climate impacts of country-level primary carbonaceous aerosol from solid-fuel cookstove emissions

International Nuclear Information System (INIS)

Lacey, Forrest; Henze, Daven

2015-01-01

Cookstove use is globally one of the largest unregulated anthropogenic sources of primary carbonaceous aerosol. While reducing cookstove emissions through national-scale mitigation efforts has clear benefits for improving indoor and ambient air quality, and significant climate benefits from reduced green-house gas emissions, climate impacts associated with reductions to co-emitted black (BC) and organic carbonaceous aerosol are not well characterized. Here we attribute direct, indirect, semi-direct, and snow/ice albedo radiative forcing (RF) and associated global surface temperature changes to national-scale carbonaceous aerosol cookstove emissions. These results are made possible through the use of adjoint sensitivity modeling to relate direct RF and BC deposition to emissions. Semi- and indirect effects are included via global scaling factors, and bounds on these estimates are drawn from current literature ranges for aerosol RF along with a range of solid fuel emissions characterizations. Absolute regional temperature potentials are used to estimate global surface temperature changes. Bounds are placed on these estimates, drawing from current literature ranges for aerosol RF along with a range of solid fuel emissions characterizations. We estimate a range of 0.16 K warming to 0.28 K cooling with a central estimate of 0.06 K cooling from the removal of cookstove aerosol emissions. At the national emissions scale, countries’ impacts on global climate range from net warming (e.g., Mexico and Brazil) to net cooling, although the range of estimated impacts for all countries span zero given uncertainties in RF estimates and fuel characterization. We identify similarities and differences in the sets of countries with the highest emissions and largest cookstove temperature impacts (China, India, Nigeria, Pakistan, Bangladesh and Nepal), those with the largest temperature impact per carbon emitted (Kazakhstan, Estonia, and Mongolia), and those that would provide the

Global climate impacts of country-level primary carbonaceous aerosol from solid-fuel cookstove emissions

Science.gov (United States)

Lacey, Forrest; Henze, Daven

2015-11-01

Cookstove use is globally one of the largest unregulated anthropogenic sources of primary carbonaceous aerosol. While reducing cookstove emissions through national-scale mitigation efforts has clear benefits for improving indoor and ambient air quality, and significant climate benefits from reduced green-house gas emissions, climate impacts associated with reductions to co-emitted black (BC) and organic carbonaceous aerosol are not well characterized. Here we attribute direct, indirect, semi-direct, and snow/ice albedo radiative forcing (RF) and associated global surface temperature changes to national-scale carbonaceous aerosol cookstove emissions. These results are made possible through the use of adjoint sensitivity modeling to relate direct RF and BC deposition to emissions. Semi- and indirect effects are included via global scaling factors, and bounds on these estimates are drawn from current literature ranges for aerosol RF along with a range of solid fuel emissions characterizations. Absolute regional temperature potentials are used to estimate global surface temperature changes. Bounds are placed on these estimates, drawing from current literature ranges for aerosol RF along with a range of solid fuel emissions characterizations. We estimate a range of 0.16 K warming to 0.28 K cooling with a central estimate of 0.06 K cooling from the removal of cookstove aerosol emissions. At the national emissions scale, countries’ impacts on global climate range from net warming (e.g., Mexico and Brazil) to net cooling, although the range of estimated impacts for all countries span zero given uncertainties in RF estimates and fuel characterization. We identify similarities and differences in the sets of countries with the highest emissions and largest cookstove temperature impacts (China, India, Nigeria, Pakistan, Bangladesh and Nepal), those with the largest temperature impact per carbon emitted (Kazakhstan, Estonia, and Mongolia), and those that would provide the

Albertans and climate change : taking action

International Nuclear Information System (INIS)

2002-10-01

This paper establishes a final framework to reduce greenhouse gas emissions in the province of Alberta. It is based on the draft plan released in May 2002 which presents actions to reduce greenhouse gas (GHG) emissions by 50 per cent below 1990 levels (a 60 million tonne reduction) by the year 2020. The plan also includes an interim reduction of 22 per cent (20 million tonnes) below a business-as-usual scenario, by 2010. The plan will be achieved through agreements negotiated with key industry sectors and will backed by regulations. The plan focuses on energy efficiency, and supports development of new technology to control industrial emissions and promotes increased use of renewable energy sources such as solar, wind and hydro power. The Alberta government will develop a definition for eligible greenhouse gas offsets, establish a registry for greenhouse gas offsets, and participate in initiatives to buy real emission reductions. The provincial government will also cut greenhouse gas emissions from its own operations by more than 20 per cent compared to 1990 levels. Royalty credits will be created for demonstration projects using carbon dioxide for enhanced oil recovery. This report presents the goals and timelines for each action that addresses climate change. It offers an alternative to the Kyoto Protocol and is focused on a technologically driven solution, instead of a politically driven one. Energy conservation and efficiency is a major part of the climate change response. In addition, the actions developed will be compatible with the United States in order to maintain competitiveness. 1 tab

Climate change and WTO : boundary mediation on certified emission reductions

International Nuclear Information System (INIS)

Kim, Ho Cheol

2011-07-01

This book mentions climate change and WTO with is climate change true? International effort for reduce of greenhouse gas with UNFCCC, Kyoto protocol, Copenhagen Accord and Cancun Agreement, WTO norm, discussion on introduction of boundary mediation on certified emission reductions, analysis on regulation related WTO norm, violation of regulation on border measure of prohibition, violation of principle on GATT, justification, except through Article 20 of GATT, assessment of policy and supplementation on the law.

Aligning corporate greenhouse-gas emissions targets with climate goals

NARCIS (Netherlands)

Krabbe, Oskar; Linthorst, Giel; Blok, Kornelis; Crijns-Graus, Wina; Vuuren, Van Detlef P.; Höhne, Niklas; Faria, Pedro; Aden, Nate; Pineda, Alberto Carrillo

2015-01-01

Corporate climate action is increasingly considered important in driving the transition towards a low-carbon economy. For this, it is critical to ensure translation of global goals to greenhouse-gas (GHG) emissions reduction targets at company level. At the moment, however, there is a lack of

Aligning corporate greenhouse-gas emissions targets with climate goals

NARCIS (Netherlands)

Krabbe, Oskar; Linthorst, Giel; Blok, Kornelis|info:eu-repo/dai/nl/07170275X; Crijns-Graus, Wina|info:eu-repo/dai/nl/308005015; Van Vuuren, Detlef P.|info:eu-repo/dai/nl/11522016X; Höhne, Niklas; Faria, Pedro; Aden, Nate; Pineda, Alberto Carrillo

2015-01-01

Corporate climate action is increasingly considered important in driving the transition towards a low-carbon economy. For this, it is critical to ensure translation of global goals to greenhouse-gas (GHG) emissions reduction targets at company level. At the moment, however, there is a lack of clear

Contribution of climate-driven change in continental water storage to recent sea-level rise

Science.gov (United States)

Milly, P. C. D.; Cazenave, A.; Gennero, C.

2003-01-01

Using a global model of continental water balance, forced by interannual variations in precipitation and near-surface atmospheric temperature for the period 1981–1998, we estimate the sea-level changes associated with climate-driven changes in storage of water as snowpack, soil water, and ground water; storage in ice sheets and large lakes is not considered. The 1981–1998 trend is estimated to be 0.12 mm/yr, and substantial interannual fluctuations are inferred; for 1993–1998, the trend is 0.25 mm/yr. At the decadal time scale, the terrestrial contribution to eustatic (i.e., induced by mass exchange) sea-level rise is significantly smaller than the estimated steric (i.e., induced by density changes) trend for the same period, but is not negligibly small. In the model the sea-level rise is driven mainly by a downtrend in continental precipitation during the study period, which we believe was generated by natural variability in the climate system. PMID:14576277

Effectiveness of state climate and energy policies in reducing power-sector CO2 emissions

Science.gov (United States)

Martin, Geoff; Saikawa, Eri

2017-12-01

States have historically been the primary drivers of climate change policy in the US, particularly with regard to emissions from power plants. States have implemented policies designed either to directly curb greenhouse gas (GHG) emissions from power plants, or to encourage energy efficiency and renewable energy growth. With the federal government withdrawing from the global climate agreement, understanding which state-level policies have successfully mitigated power-plant emissions is urgent. Past research has assessed policy effectiveness using data for periods before the adoption of many policies. We assess 17 policies using the latest data on state-level power-sector CO2 emissions. We find that policies with mandatory compliance are reducing power-plant emissions, while voluntary policies are not. Electric decoupling, mandatory GHG registry/reporting and public benefit funds are associated with the largest reduction in emissions. Mandatory GHG registry/reporting and public benefit funds are also associated with a large reduction in emissions intensity.

Emission of electromagnetic radiation from beam driven plasmas

International Nuclear Information System (INIS)

Newman, D.L.

1985-01-01

Two production mechanisms for electromagnetic radiation from a plasma containing electron-beam-driven weak Langmuir turbulence are studied: induced Compton conversion and two-Langmuir-wave coalescence. Induced Compton conversion in which a Langmuir wave scatters off a relativistic electron while converting into a transversely polarized electromagnetic wave is considered as a means for producing amplified electromagnetic radiation from a beam-plasma system at frequencies well above the electron plasma frequency. The induced emission growth rates of the radiation produced by a monoenergetic ultrarelativistic electron beam are determined as a function of the Langmuir turbulence spectrum in the background plasma and are numerically evaluated for a range of model Langmuir spectra. Induced Compton conversion can play a role in emission from astrophysical beam-plasma systems if the electron beam is highly relativistic and sufficiently narrow. However, it is found that the growth rates for this process are too small in all cases studied to account for the intense high-frequency radiation observed in laboratory experiments. Two-Langmuir-wave coalescence as a means of producing radiation at 2omega/sub p/ is investigated in the setting of the earth's foreshock

Impacts of transportation sector emissions on future U.S. air quality in a changing climate. Part II: Air quality projections and the interplay between emissions and climate change.

Science.gov (United States)

Campbell, Patrick; Zhang, Yang; Yan, Fang; Lu, Zifeng; Streets, David

2018-07-01

In Part II of this work we present the results of the downscaled offline Weather Research and Forecasting/Community Multiscale Air Quality (WRF/CMAQ) model, included in the "Technology Driver Model" (TDM) approach to future U.S. air quality projections (2046-2050) compared to a current-year period (2001-2005), and the interplay between future emission and climate changes. By 2046-2050, there are widespread decreases in future concentrations of carbon monoxide (CO), nitrogen oxides (NO x  = NO + NO 2 ), volatile organic compounds (VOCs), ammonia (NH 3 ), sulfur dioxide (SO 2 ), and particulate matter with an aerodynamic diameter ≤ 2.5 μm (PM 2.5 ) due mainly to decreasing on-road vehicle (ORV) emissions near urban centers as well as decreases in other transportation modes that include non-road engines (NRE). However, there are widespread increases in daily maximum 8-hr ozone (O 3 ) across the U.S., which are due to enhanced greenhouse gases (GHG) including methane (CH 4 ) and carbon dioxide (CO 2 ) under the Intergovernmental Panel on Climate Change (IPCC) A1B scenario, and isolated areas of larger reduction in transportation emissions of NO x compared to that of VOCs over regions with VOC-limited O 3 chemistry. Other notable future changes are reduced haze and improved visibility, increased primary organic to elemental carbon ratio, decreases in PM 2.5 and its species, decreases and increases in dry deposition of SO 2 and O 3 , respectively, and decreases in total nitrogen (TN) deposition. There is a tendency for transportation emission and CH 4 changes to dominate the increases in O 3 , while climate change may either enhance or mitigate these increases in the west or east U.S., respectively. Climate change also decreases PM 2.5 in the future. Other variable changes exhibit stronger susceptibility to either emission (e.g., CO, NO x , and TN deposition) or climate changes (e.g., VOC, NH 3 , SO 2 , and total sulfate deposition), which also have a strong

Responses of non-methane biogenic volatile organic compound emissions to climate change in boreal and subarctic ecosystems

Energy Technology Data Exchange (ETDEWEB)

Faubert, P.

2010-07-01

Non-methane biogenic volatile organic compound emissions (BVOCs) have important roles in the global atmospheric chemistry but their feedbacks to climate change are still unknown. This thesis reports one of the first estimates of BVOC emissions from boreal and subarctic ecosystems. Most importantly, this thesis assesses the BVOC emission responses to four effects of climate change in these ecosystems: (1) the direct effect of warming, and its indirect effects via (2) water table drawdown, (3) change in the vegetation composition, and (4) enhanced UV-B radiation. BVOC emissions were measured using a conventional chamber method in which the compounds were collected on adsorbent and later analyzed by gas chromatography-mass spectrometry. On a subarctic heath, warming by only 1.9-2.5 degC doubled the monoterpene and sesquiterpene emissions. Such a high increase of BVOC emissions under a conservative warming cannot be predicted by the current models, which underlines the importance of a focus on BVOC emissions from the Subarctic under climate change. On a subarctic peatland, enhanced UV-B did not affect the BVOC emissions but the water table level exerted the major effect. The water table drawdown experimentally applied on boreal peatland microcosms decreased the emissions of monoterpenes and other VOCs (BVOCs with a lifetime>1 d) for the hollows (wet microsites) and that of all BVOC groups for the lawns (moderately wet microsites). The warming treatment applied on the lawn microcosms decreased the isoprene emission. The removal of vascular plants in the hummock (dry microsites) microcosms decreased the emissions of monoterpenes while the emissions between the microcosms covered with Sphagnum moss and bare peat were not different. In conclusion, the results presented in this thesis indicate that climate change has complex effects on the BVOC emissions. These results make a significant contribution to improving the modeling of BVOC emissions for a better understanding of

Climate-driven polar motion

Science.gov (United States)

Celaya, Michael A.; Wahr, John M.; Bryan, Frank O.

1999-06-01

The output of a coupled climate system model provides a synthetic climate record with temporal and spatial coverage not attainable with observational data, allowing evaluation of climatic excitation of polar motion on timescales of months to decades. Analysis of the geodetically inferred Chandler excitation power shows that it has fluctuated by up to 90% since 1900 and that it has characteristics representative of a stationary Gaussian process. Our model-predicted climate excitation of the Chandler wobble also exhibits variable power comparable to the observed. Ocean currents and bottom pressure shifts acting together can alone drive the 14-month wobble. The same is true of the excitation generated by the combined effects of barometric pressure and winds. The oceanic and atmospheric contributions are this large because of a relatively high degree of constructive interference between seafloor pressure and currents and between atmospheric pressure and winds. In contrast, excitation by the redistribution of water on land appears largely insignificant. Not surprisingly, the full climate effect is even more capable of driving the wobble than the effects of the oceans or atmosphere alone are. Our match to the observed annual excitation is also improved, by about 17%, over previous estimates made with historical climate data. Efforts to explain the 30-year Markowitz wobble meet with less success. Even so, at periods ranging from months to decades, excitation generated by a model of a coupled climate system makes a close approximation to the amplitude of what is geodetically observed.

Etude Climat no. 33 'Joint Implementation: a frontier mechanism within the borders of an emissions cap'

International Nuclear Information System (INIS)

Shishlov, Igor; Bellassen, Valentin; Leguet, Benoit

2012-01-01

Among the publications of CDC Climat Research, 'Climate Reports' offer in-depth analyses on a given subject. This issue addresses the following points: Based on specific projects rather than economy-wide emissions reductions, and driven by the demand from the installations covered by the European Union Emissions Trading Scheme (EU ETS), Joint Implementation (JI) turned out to be a largely private sector mechanism. Besides attracting private investors in GHG abatement projects, JI creates an opportunity for countries to exploit the arbitrage price spread between different carbon offsets: Emission Reduction Units (ERU), the credits issued from JI projects, trade with a premium of up to 50% over Assigned Amount Units (AAU), the country-level carbon allowances. Some countries, like for instance Ukraine, quickly realized the added value of JI and boosted its development, while in others, like Russia, JI lacked political support and efficient frameworks took time to be established. According to the ERU supply forecasting model developed by CDC Climat Research, Annex I countries are expected to generate up to 356 million ERUs for the first Kyoto commitment period. Around 80% of these credits shall originate from Russia and Ukraine, and up to 70 million shall be generated from countries participating in the EU ETS. Within the EU, JI has been used as a 'frontier mechanism': JI projects mostly explored abatement opportunities not covered by the scheme and, as highlighted by the case of nitrous oxide emissions from the production of nitric acid, played an important role in identifying abatement technologies and providing information to extend the scope of the EU ETS. One of the most complex issues related to JI is the practice of additionality. The cases of France and Ukraine demonstrate that the stakes associated with additionality may differ depending on a country's compliance position. In Ukraine, additionality was not perceived as a significant economic risk due to a

Human amplification of drought-driven fire in tropical regions

Science.gov (United States)

Tosca, Michael

2015-04-01

The change in globally-measured radiative forcing from the pre-industrial to the present due to interactions between aerosol particles and cloud cover has the largest uncertainty of all anthropogenic factors. Uncertainties are largest in the tropics, where total cloud amount and incoming solar radiation are highest, and where 50% of all aerosol emissions originate from anthropogenic fire. It is well understood that interactions between smoke particles and cloud droplets modify cloud cover , which in turn affects climate, however, few studies have observed the temporal nature of aerosol-cloud interactions without the use of a model. Here we apply a novel approach to measure the effect of fire aerosols on convective clouds in tropical regions (Brazil, Africa and Indonesia) through a combination of remote sensing and meteorological data. We attribute a reduction in cloud fraction during periods of high aerosol optical depths to a smoke-driven inhibition of convection. We find that higher smoke burdens limit vertical updrafts, increase surface pressure, and increase low- level divergence-meteorological indicators of convective suppression. These results are corroborated by climate model simulations that show a smoke-driven increase in regionally averaged shortwave tropospheric heating and boundary layer stratification, and a decrease in vertical velocity and precipitation during the fire season (December-February). We then quantify the human response to decreased cloud cover using a combination of socioeconomic and climate data Our results suggest that, in tropical regions, anthropogenic fire initiates a positive feedback loop where increased aerosol emissions limit convection, dry the surface and enable increased fire activity via human ignition. This result has far-reaching implications for fire management and climate policy in emerging countries along the equator that utilize fire.

Isoprene emissions over Asia 1979-2012: impact of climate and land use changes

Science.gov (United States)

Stavrakou, T.; Müller, J.-F.; Bauwens, M.; De Smedt, I.; Van Roozendael, M.; Guenther, A.; Wild, M.; Xia, X.

2013-11-01

Due to the scarcity of observational constraints and the rapidly changing environment in East and Southeast Asia, isoprene emissions predicted by models are expected to bear substantial uncertainties. The aim of this study is to improve upon the existing bottom-up estimates, and investigate the temporal evolution of the fluxes in Asia over 1979-2012. To this purpose, we calculate the hourly emissions at 0.5° × 0.5° resolution using the MEGAN-MOHYCAN model driven by ECMWF ERA-Interim climatology. This study incorporates (i) changes in land use, including the rapid expansion of oil palms, (ii) meteorological variability according to ERA-Interim, (iii) long-term changes in solar radiation (dimming/brightening) constrained by surface network radiation measurements, and (iv) recent experimental evidence that South Asian tropical forests are much weaker isoprene emitters than previously assumed, and on the other hand, that oil palms hold a strong isoprene emission capacity. These effects lead to a significant lowering (factor of two) in the total isoprene fluxes over the studied domain, and to emission reductions reaching a~factor of 3.5 in Southeast Asia. The bottom-up annual isoprene emissions for 2005 are estimated at 7.0, 4.8, 8.3, 2.9 Tg in China, India, Indonesia and Malaysia, respectively. Changes in temperature and solar radiation are the major drivers of the interannual variability and trend in the emissions. An annual positive flux trend of 0.2% and 0.52% is found in Asia and China, respectively, through the entire period, related to positive trend in temperature and solar radiation. The impact of oil palm expansion in Indonesia and Malaysia is to enhance the trends over that region, e.g. from 1.17% to 1.5% in 1979-2005 in Malaysia. A negative emission trend is derived in India (-0.4%), owing to the negative trend in solar radiation data associated to the strong dimming effect likely due to increasing aerosol loadings. The bottom-up emissions are evaluated

LEDS Global Partnership in Action: Advancing Climate-Resilient Low Emission Development Around the World (Fact Sheet)

Energy Technology Data Exchange (ETDEWEB)

2013-11-01

Many countries around the globe are designing and implementing low emission development strategies (LEDS). These LEDS seek to achieve social, economic, and environmental development goals while reducing long-term greenhouse gas (GHG) emissions and increasing resiliency to climate change impacts. The LEDS Global Partnership (LEDS GP) harnesses the collective knowledge and resources of more than 120 countries and international donor and technical organizations to strengthen climate-resilient low emission development efforts around the world.

Climate of opinion risks undermining war on emissions

Energy Technology Data Exchange (ETDEWEB)

Shepherd, John [nuclear 24, London (United Kingdom)

2014-06-15

Analysts in the US are becomingly increasingly vocal about how policies that are designed to combat the effects of climate change risk doing the exact opposite, because they are so heavily in favour of 'renewables' that they are putting increasing pressure on the country's biggest source of zero-emissions power - nuclear. What makes this and reports interesting reading is that the so-called 'German experience' - where nuclear power continues to be gradually phased out for political reasons - is proving a sobering thought for the US. Policies that force nuclear out of the mix of resources with which to combat climate change will prove to be short-sighted and the consequences far reaching. (orig.)

Spatially explicit integrated modeling and economic valuation of climate driven land use change and its indirect effects.

OpenAIRE

Bateman, Ian; Agarwala, M.; Binner, A.; Coombes, E.; Day, B.; Ferrini, Silvia; Fezzi, C.; Hutchins, M.; Lovett, A.; Posen, P.

2016-01-01

We present an integrated model of the direct consequences of climate change on land use, and the indirect effects of induced land use change upon the natural environment. The model predicts climate-driven shifts in the profitability of alternative uses of agricultural land. Both the direct impact of climate change and the induced shift in land use patterns will cause secondary effects on the water environment, for which agriculture is the major source of diffuse pollution. We model the impact...

Regional impacts of climate change and atmospheric CO2 on future ocean carbon uptake: A multi-model linear feedback analysis

OpenAIRE

Roy Tilla; Bopp Laurent; Gehlen Marion; Schneider Birgitt; Cadule Patricia; Frölicher Thomas; Segschneider Jochen; Tijputra Jerry; Heinze Christoph; Joos Fortunat

2011-01-01

The increase in atmospheric CO2 over this century depends on the evolution of the oceanic air–sea CO2 uptake which will be driven by the combined response to rising atmospheric CO2 itself and climate change. Here the future oceanic CO2 uptake is simulated using an ensemble of coupled climate–carbon cycle models. The models are driven by CO2 emissions from historical data and the Special Report on Emissions Scenarios (SRES) A2 high emission scenario. A linear feedback analysis successfully sep...

Deforestation and agriculture in the tropics: carbon emissions and options for mitigation

NARCIS (Netherlands)

Carter, Sarah

2018-01-01

Agriculture is the largest driver of deforestation globally, and this conversion of land from forests to agriculture, results in emissions which are contributing to climate change. This thesis focuses on exploring agriculture-driven deforestation at the country level, from the perspective of

Climate-driven introduction of the Black Death and successive plague reintroductions into Europe

Czech Academy of Sciences Publication Activity Database

Schmid, B. V.; Büntgen, Ulf; Easterday, W. R.; Ginzler, Ch.; Walloe, L.; Bramanti, B.; Stenseth, N. C.

2015-01-01

Roč. 112, č. 10 (2015), s. 3020-3025 ISSN 0027-8424 Institutional support: RVO:67179843 Keywords : yersinia-pestis * xenopsylla-cheopis * bubonic plague * central-asia * synchrony * dynamics * transmission * temperature * populations * thresholds * Yersinia pestis * medieval epidemiology * climate-driven disease dynamics Subject RIV: EH - Ecology, Behaviour Impact factor: 9.423, year: 2015 http://www.pnas.org/content/112/10/3020.full.pdf

Climate Change and employment. Impact on employment in the European Union-25 of climate change and CO2 emission reduction measures by 2030

Energy Technology Data Exchange (ETDEWEB)

Dupressoir, S.; Belen Sanchez, A.; Bobe, P.; Hoefele, V. (and others)

2007-05-15

This study was intended provide an analysis of the potential costs and benefits for employment of the policies and measures against climate change as well as of the manifestations of the consequences of climate change in Europe. This report comprises two divisions. The first, entitled 'Impact of climate change', attempts to determine the potential impact on employment in Europe of the consequences of climate change (Part 1). The second, entitled 'Impact of CO2 emission reduction measures', analyses the potential implications for employment of climate-change prevention policies in the EU with time-horizons of 2012 and 2030 (Parts 2 to 4). The conclusions and recommendations of the study appear in four parts : Part 1 analyses the potential consequences for employment of climatic warming in Europe; Part 2 presents the objectives, the hypotheses and the methodology of the 'impact of CO2 emission reduction measures' division; Part 3 analyses the foreseeable effects of CO2 emission reduction measures on employment in Europe; Part 4 offers general (or sector-wide) recommendations for measures and policies to promote positive effects and prevent negative effects. The concluding part discusses the uncertainties and identifies the questions deserving further investigation.

Influence of urbanization-driven land use/cover change on climate: The case of Addis Ababa, Ethiopia

Science.gov (United States)

Arsiso, Bisrat Kifle; Mengistu Tsidu, Gizaw; Stoffberg, Gerrit Hendrik; Tadesse, Tsegaye

2018-06-01

Land use change is the second most important anthropogenic influence on climate beside the emission of greenhouse gases. Urbanization is leading to significant land use changes in Africa since the continent is undergoing rapid urbanization and population growth in recent decades. Addis Ababa is one of these fast growing cities in the continent. Therefore, detection of land use change is very important to identify its impact on climate and sustainable land use management of the city. The study used Landsat images to generate land use/land cover change map for the city. The normalized difference vegetation index (NDVI) is used to detect the major changes of vegetation cover occurred between 1986 and 2011 as a result of land use and land cover change. Downscaled HadCM3 simulations under A2 and B2 emission scenarios is used to investigate future urban heat island (UHI) over the city of Addis Ababa. In the city, the analysis of Landsat images has shown that the built-up areas have increased by 121.88 km2 within the last 25 years. This finding is consistent with NDVI images taken over the same period that reveal a decline in vegetation cover. The impact of the urbanization-driven land use/cover change has resulted in notable nocturnal urban heat island (UHI) as revealed from an average increase in minimum temperature of 1.5 °C at the centre of the city relative to rural site over the 1960-2001 period. The mean of the 2006-2010 spatial minimum temperature anomaly with respect to the base period mean of 1981-2005 is consistent with the observed UHI. The temperature in the central areas (both commercial and residential sectors) of Addis Ababa is warmer than the surrounding areas. The thermal gradient increase from about 1.44 °C at the centre (Arada, Addis Ketema, Lideta and Kirkos) to 0.21 °C at the peripheral parts of the city (Gulele, Bole, Nefasilk-Lafto, Kolfe Keranio and east of Yeka sub-cities) transecting across the hot (high-density urban) to moderately warm to

Designing an emissions trading scheme for China—An up-to-date climate policy assessment

International Nuclear Information System (INIS)

Hübler, Michael; Voigt, Sebastian; Löschel, Andreas

2014-01-01

We assess recent Chinese climate policy proposals in a multi-region, multi-sector computable general equilibrium model with a Chinese carbon emissions trading scheme (ETS). When the emissions intensity per GDP in 2020 is required to be 45% lower than in 2005, the model simulations indicate that the climate policy induced welfare loss in 2020, measured as the level of GDP and welfare in 2020 under climate policy relative to their level under business-as-usual (BAU) in the same year, is about 1%. The Chinese welfare loss in 2020 slightly increases in the Chinese rate of economic growth in 2020. When keeping the emissions target fixed at the 2020 level after 2020 in absolute terms, the welfare loss will reach about 2% in 2030. If China's annual economic growth rate is 0.5 percentage points higher (lower), the climate policy-induced welfare loss in 2030 will rise (decline) by about 0.5 percentage points. Full auctioning of carbon allowances results in very similar macroeconomic effects as free allocation, but full auctioning leads to higher reductions in output than free allocation for ETS sectors. Linking the Chinese to the European ETS and restricting the transfer volume to one third of the EU's reduction effort creates at best a small benefit for China, yet with smaller sectoral output reductions than auctioning. These results highlight the importance of designing the Chinese ETS wisely. - Highlights: • 45% Chinese carbon intensity target for 2020 implemented via emissions trading. • 1% GDP/welfare loss in 2020 and 2% in 2030 for a fixed emissions target after 2020. • 0.5 percentage points higher (lower) growth, increases (decreases) climate policy-induced welfare loss in 2030 by about 0.5 percentage points. • Similar macroeconomic effects for free allocation and full auctioning, but higher reductions in output under full auctioning in ETS sectors. • Restricted linking to EU emissions trading creates at best a small benefit for China

Sensitivity of Water Scarcity Events to ENSO-Driven Climate Variability at the Global Scale

Science.gov (United States)

Veldkamp, T. I. E.; Eisner, S.; Wada, Y.; Aerts, J. C. J. H.; Ward, P. J.

2015-01-01

Globally, freshwater shortage is one of the most dangerous risks for society. Changing hydro-climatic and socioeconomic conditions have aggravated water scarcity over the past decades. A wide range of studies show that water scarcity will intensify in the future, as a result of both increased consumptive water use and, in some regions, climate change. Although it is well-known that El Niño- Southern Oscillation (ENSO) affects patterns of precipitation and drought at global and regional scales, little attention has yet been paid to the impacts of climate variability on water scarcity conditions, despite its importance for adaptation planning. Therefore, we present the first global-scale sensitivity assessment of water scarcity to ENSO, the most dominant signal of climate variability. We show that over the time period 1961-2010, both water availability and water scarcity conditions are significantly correlated with ENSO-driven climate variability over a large proportion of the global land area (> 28.1 %); an area inhabited by more than 31.4% of the global population. We also found, however, that climate variability alone is often not enough to trigger the actual incidence of water scarcity events. The sensitivity of a region to water scarcity events, expressed in terms of land area or population exposed, is determined by both hydro-climatic and socioeconomic conditions. Currently, the population actually impacted by water scarcity events consists of 39.6% (CTA: consumption-to-availability ratio) and 41.1% (WCI: water crowding index) of the global population, whilst only 11.4% (CTA) and 15.9% (WCI) of the global population is at the same time living in areas sensitive to ENSO-driven climate variability. These results are contrasted, however, by differences in growth rates found under changing socioeconomic conditions, which are relatively high in regions exposed to water scarcity events. Given the correlations found between ENSO and water availability and scarcity

Heat-Related Mortality in a Warming Climate: Projections for 12 U.S. Cities

Directory of Open Access Journals (Sweden)

Elisaveta P. Petkova

2014-10-01

Full Text Available Heat is among the deadliest weather-related phenomena in the United States, and the number of heat-related deaths may increase under a changing climate, particularly in urban areas. Regional adaptation planning is unfortunately often limited by the lack of quantitative information on potential future health responses. This study presents an assessment of the future impacts of climate change on heat-related mortality in 12 cities using 16 global climate models, driven by two scenarios of greenhouse gas emissions. Although the magnitude of the projected heat effects was found to differ across time, cities, climate models and greenhouse pollution emissions scenarios, climate change was projected to result in increases in heat-related fatalities over time throughout the 21st century in all of the 12 cities included in this study. The increase was more substantial under the high emission pathway, highlighting the potential benefits to public health of reducing greenhouse gas emissions. Nearly 200,000 heat-related deaths are projected to occur in the 12 cities by the end of the century due to climate warming, over 22,000 of which could be avoided if we follow a low GHG emission pathway. The presented estimates can be of value to local decision makers and stakeholders interested in developing strategies to reduce these impacts and building climate change resilience.

Heat-Related Mortality in a Warming Climate: Projections for 12 U.S. Cities

Science.gov (United States)

Petkova, Elisaveta P.; Bader, Daniel A.; Anderson, G. Brooke; Horton, Radley M.; Knowlton, Kim; Kinney, Patrick L.

2014-01-01

Heat is among the deadliest weather-related phenomena in the United States, and the number of heat-related deaths may increase under a changing climate, particularly in urban areas. Regional adaptation planning is unfortunately often limited by the lack of quantitative information on potential future health responses. This study presents an assessment of the future impacts of climate change on heat-related mortality in 12 cities using 16 global climate models, driven by two scenarios of greenhouse gas emissions. Although the magnitude of the projected heat effects was found to differ across time, cities, climate models and greenhouse pollution emissions scenarios, climate change was projected to result in increases in heat-related fatalities over time throughout the 21st century in all of the 12 cities included in this study. The increase was more substantial under the high emission pathway, highlighting the potential benefits to public health of reducing greenhouse gas emissions. Nearly 200,000 heat-related deaths are projected to occur in the 12 cities by the end of the century due to climate warming, over 22,000 of which could be avoided if we follow a low GHG emission pathway. The presented estimates can be of value to local decision makers and stakeholders interested in developing strategies to reduce these impacts and building climate change resilience.

A Data-Driven Assessment of the Sensitivity of Global Ecosystems to Climate Anomalies

Science.gov (United States)

Miralles, D. G.; Papagiannopoulou, C.; Demuzere, M.; Decubber, S.; Waegeman, W.; Verhoest, N.; Dorigo, W.

2017-12-01

Vegetation is a central player in the climate system, constraining atmospheric conditions through a series of feedbacks. This fundamental role highlights the importance of understanding regional drivers of ecological sensitivity and the response of vegetation to climatic changes. While nutrient availability and short-term disturbances can be crucial for vegetation at various spatiotemporal scales, natural vegetation dynamics are overall driven by climate. At monthly scales, the interactions between vegetation and climate become complex: some vegetation types react preferentially to specific climatic changes, with different levels of intensity, resilience and lagged response. For our current Earth System Models (ESMs) being able to capture this complexity is crucial but extremely challenging. This adds uncertainty to our projections of future climate and the fate of global ecosystems. Here, following a Granger causality framework based on a non-linear random forest predictive model, we exploit the current wealth of satellite data records to uncover the main climatic drivers of monthly vegetation variability globally. Results based on three decades of satellite data indicate that water availability is the most dominant factor driving vegetation in over 60% of the vegetated land. This overall dependency of ecosystems on water availability is larger than previously reported, partly owed to the ability of our machine-learning framework to disentangle the co-linearites between climatic drivers, and to quantify non-linear impacts of climate on vegetation. Our observation-based results are then used to benchmark ESMs on their representation of vegetation sensitivity to climate and climatic extremes. Our findings indicate that the sensitivity of vegetation to climatic anomalies is ill-reproduced by some widely-used ESMs.

Committed climate change due to historical land use and management: the concept

Science.gov (United States)

Freibauer, Annette; Dolman, Han; Don, Axel; Poeplau, Christopher

2013-04-01

A significant fraction of the European land surface has changed its land use over the last 50 years. Management practices have changed in the same period in most land use systems. These changes have affected the carbon and greenhouse gas (GHG) balance of the European land surface. Land use intensity, defined here loosely as the degree to which humans interfere with the land, strongly affects GHG emissions. Land use and land management changes suggest that the variability of the carbon balance and of GHG emissions of cultivated land areas in Europe is much more driven by land use history and management than driven by climate. Importantly changes in land use and its management have implications for future GHG emissions, and therefore present a committed climate change, defined as inevitable future additional climate change induced by past human activity. It is one of the key goals of the large-scale integrating research project "GHG-Europe - Greenhouse gas management in European land use systems" to quantify the committed climate change due to legacy effects by land use and management. The project is funded by the European Commission in the 7th framework programme (Grant agreement no.: 244122). This poster will present the conceptual approach taken to reach this goal. (1) First of all we need to proof that at site, or regional level the management effects are larger than climate effects on carbon balance and GHG emissions. Observations from managed sites and regions will serve as empirical basis. Attribution experiments with models based on process understanding are run on managed sites and regions will serve to demonstrate that the observed patterns of the carbon balance and GHG emissions can only be reproduced when land use and management are included as drivers. (2) The legacy of land use changes will be quantified by combining spatially explicit time series of land use changes with response functions of carbon pools. This will allow to separate short-term and

Assessing "dangerous climate change": required reduction of carbon emissions to protect young people, future generations and nature.

Directory of Open Access Journals (Sweden)

James Hansen

Full Text Available We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth's measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today's young people, future generations, and nature. A cumulative industrial-era limit of ∼500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of ∼1000 GtC, sometimes associated with 2°C global warming, would spur "slow" feedbacks and eventual warming of 3-4°C with disastrous consequences. Rapid emissions reduction is required to restore Earth's energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels.

Assessing "dangerous climate change": required reduction of carbon emissions to protect young people, future generations and nature.

Science.gov (United States)

Hansen, James; Kharecha, Pushker; Sato, Makiko; Masson-Delmotte, Valerie; Ackerman, Frank; Beerling, David J; Hearty, Paul J; Hoegh-Guldberg, Ove; Hsu, Shi-Ling; Parmesan, Camille; Rockstrom, Johan; Rohling, Eelco J; Sachs, Jeffrey; Smith, Pete; Steffen, Konrad; Van Susteren, Lise; von Schuckmann, Karina; Zachos, James C

2013-01-01

We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth's measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today's young people, future generations, and nature. A cumulative industrial-era limit of ∼500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of ∼1000 GtC, sometimes associated with 2°C global warming, would spur "slow" feedbacks and eventual warming of 3-4°C with disastrous consequences. Rapid emissions reduction is required to restore Earth's energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels.

Assessing 'Dangerous Climate Change': Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature

Science.gov (United States)

Hansen, James; Kharecha, Pushker; Sato, Makiko; Masson-Demotte, Valerie; Ackerman, Frank; Beerling, David J.; Hearty, Paul J.; Hoegh-Guldberg, Ove; Hsu, Shi-Ling; Parmesan, Camille;

Climate-driven ichthyoplankton drift model predicts growth of top predator young.

Science.gov (United States)

Myksvoll, Mari S; Erikstad, Kjell E; Barrett, Robert T; Sandvik, Hanno; Vikebø, Frode

2013-01-01

Climate variability influences seabird population dynamics in several ways including access to prey near colonies during the critical chick-rearing period. This study addresses breeding success in a Barents Sea colony of common guillemots Uria aalge where trophic conditions vary according to changes in the northward transport of warm Atlantic Water. A drift model was used to simulate interannual variations in transport of cod Gadus morhua larvae along the Norwegian coast towards their nursery grounds in the Barents Sea. The results showed that the arrival of cod larvae from southern spawning grounds had a major effect on the size of common guillemot chicks at fledging. Furthermore, the fraction of larvae from the south was positively correlated to the inflow of Atlantic Water into the Barents Sea thus clearly demonstrating the mechanisms by which climate-driven bottom-up processes influence interannual variations in reproductive success in a marine top predator.

Climate effects of a hypothetical regional nuclear war: Sensitivity to emission duration and particle composition

Science.gov (United States)

Pausata, Francesco S. R.; Lindvall, Jenny; Ekman, Annica M. L.; Svensson, Gunilla

2016-11-01

Here, we use a coupled atmospheric-ocean-aerosol model to investigate the plume development and climate effects of the smoke generated by fires following a regional nuclear war between emerging third-world nuclear powers. We simulate a standard scenario where 5 Tg of black carbon (BC) is emitted over 1 day in the upper troposphere-lower stratosphere. However, it is likely that the emissions from the fires ignited by bomb detonations include a substantial amount of particulate organic matter (POM) and that they last more than 1 day. We therefore test the sensitivity of the aerosol plume and climate system to the BC/POM ratio (1:3, 1:9) and to the emission length (1 day, 1 week, 1 month). We find that in general, an emission length of 1 month substantially reduces the cooling compared to the 1-day case, whereas taking into account POM emissions notably increases the cooling and the reduction of precipitation associated with the nuclear war during the first year following the detonation. Accounting for POM emissions increases the particle size in the short-emission-length scenarios (1 day/1 week), reducing the residence time of the injected particle. While the initial cooling is more intense when including POM emission, the long-lasting effects, while still large, may be less extreme compared to the BC-only case. Our study highlights that the emission altitude reached by the plume is sensitive to both the particle type emitted by the fires and the emission duration. Consequently, the climate effects of a nuclear war are strongly dependent on these parameters.

A Science-Driven Photojournalistic Documentation of Climate Change (Invited)

Science.gov (United States)

Braasch, G.; Rothlein, J. E.

2013-12-01

Office of the President; two original books (one for middle schools with a co-author); publication in hundreds of magazines, textbooks and public interest websites; use during university, government and civic seminars and scientific meetings; and distribution among and use by Congressional offices. Most recently the project inspired films about youth involvement in citizen science and climate change education; and co-developed Apps for the iPad and iPhone which graphically show climate-driven changes in repeat photographs and maps. Financial support for this work has come principally from publication fees and grants from small foundations and individuals (via Blue Earth Alliance of Seattle).

Estimation of Energy Consumption and Greenhouse Gas Emissions considering Aging and Climate Change in Residential Sector

Science.gov (United States)

Lee, M.; Park, C.; Park, J. H.; Jung, T. Y.; Lee, D. K.

2015-12-01

The impacts of climate change, particularly that of rising temperatures, are being observed across the globe and are expected to further increase. To counter this phenomenon, numerous nations are focusing on the reduction of greenhouse gas (GHG) emissions. Because energy demand management is considered as a key factor in emissions reduction, it is necessary to estimate energy consumption and GHG emissions in relation to climate change. Further, because South Korea is the world's fastest nation to become aged, demographics have also become instrumental in the accurate estimation of energy demands and emissions. Therefore, the purpose of this study is to estimate energy consumption and GHG emissions in the residential sectors of South Korea with regard to climate change and aging to build more accurate strategies for energy demand management and emissions reduction goals. This study, which was stablished with 2010 and 2050 as the base and target years, respectively, was divided into a two-step process. The first step evaluated the effects of aging and climate change on energy demand, and the second estimated future energy use and GHG emissions through projected scenarios. First, aging characteristics and climate change factors were analyzed by using the logarithmic mean divisia index (LMDI) decomposition analysis and the application of historical data. In the analysis of changes in energy use, the effects of activity, structure, and intensity were considered; the degrees of contribution were derived from each effect in addition to their relations to energy demand. Second, two types of scenarios were stablished based on this analysis. The aging scenarios are business as usual and future characteristics scenarios, and were used in combination with Representative Concentration Pathway (RCP) 2.6 and 8.5. Finally, energy consumption and GHG emissions were estimated by using a combination of scenarios. The results of these scenarios show an increase in energy consumption

Understanding and Improving Ocean Mixing Parameterizations for modeling Climate Change

Science.gov (United States)

Howard, A. M.; Fells, J.; Clarke, J.; Cheng, Y.; Canuto, V.; Dubovikov, M. S.

2017-12-01

Climate is vital. Earth is only habitable due to the atmosphere&oceans' distribution of energy. Our Greenhouse Gas emissions shift overall the balance between absorbed and emitted radiation causing Global Warming. How much of these emissions are stored in the ocean vs. entering the atmosphere to cause warming and how the extra heat is distributed depends on atmosphere&ocean dynamics, which we must understand to know risks of both progressive Climate Change and Climate Variability which affect us all in many ways including extreme weather, floods, droughts, sea-level rise and ecosystem disruption. Citizens must be informed to make decisions such as "business as usual" vs. mitigating emissions to avert catastrophe. Simulations of Climate Change provide needed knowledge but in turn need reliable parameterizations of key physical processes, including ocean mixing, which greatly impacts transport&storage of heat and dissolved CO2. The turbulence group at NASA-GISS seeks to use physical theory to improve parameterizations of ocean mixing, including smallscale convective, shear driven, double diffusive, internal wave and tidal driven vertical mixing, as well as mixing by submesoscale eddies, and lateral mixing along isopycnals by mesoscale eddies. Medgar Evers undergraduates aid NASA research while learning climate science and developing computer&math skills. We write our own programs in MATLAB and FORTRAN to visualize and process output of ocean simulations including producing statistics to help judge impacts of different parameterizations on fidelity in reproducing realistic temperatures&salinities, diffusivities and turbulent power. The results can help upgrade the parameterizations. Students are introduced to complex system modeling and gain deeper appreciation of climate science and programming skills, while furthering climate science. We are incorporating climate projects into the Medgar Evers college curriculum. The PI is both a member of the turbulence group at

The demography of climate-driven and density-regulated population dynamics in a perennial plant

DEFF Research Database (Denmark)

Dahlgren, Johan; Bengstsson, Karin; Ehrlén, Johan

2016-01-01

Identifying the internal and external drivers of population dynamics is a key objective in ecology, currently accentuated by the need to forecast the effects of climate change on species distributions and abundances. The interplay between environmental and density effects is one particularly...... important aspect of such forecasts. We examined the simultaneous impact of climate and intraspecific density on vital rates of the dwarf shrub Fumana procumbens over 20 yr, using generalized additive mixed models. We then analyzed effects on population dynamics using integral projection models...... to be driven solely by the environment can overestimate extinction risks if there is density dependence. We conclude that density regulation can dampen effects of climate change on Fumana population size, and discuss the need to quantify density dependence in predictions of population responses...

Significance of Future Biogenic and Fire Emissions on Regional Aerosol Burden

Science.gov (United States)

Lim, A.; Tai, A. P. K.; Val Martin, M.

2017-12-01

Land-use and land cover changes have been found to substantially affect atmospheric aerosols and climate worldwide1,2, but the complex mechanisms and pathways involved in the interactions between terrestrial processes and aerosols are not well understood. Here we use a global coupled aerosol chemistry-climate-land model (CESM with CAM5 using Modal Aerosol Module 3 and CLM4.5 in Satellite Phenology mode) to investigate how aerosols respond to future climate and land-use changes, and in turn, affects cloud cover and other hydrometeorological variables in the long term. Time-sliced simulations are conducted for a base year (2000) as a base case; then three future projected scenarios for year 2050 driven by land-use and climate projections following the Representative Concentration Pathways RCP8.53 are conducted. The first scenario considers future projected biogenic emissions, allowing us to investigate the effect of increased plant activity and enhanced biogenic emissions due to future land-use and climate on aerosol burden. The second scenario considers future biomass burning emissions, allowing us to investigate the effect of increased biomass burning emissions due to future land-use and climate on aerosol burden. The third scenario combines the projected changes in the two emissions. We find that both biogenic and biomass burning emissions contribute significantly to local aerosol and cloud condensation nuclei (CCN) concentrations. The contribution from biogenic emissions to local aerosol burden is smaller in magnitude (10% to 20%), but the effects are ubiquitous in many places globally. Meanwhile, the contribution from biomass burning emissions can be much higher in magnitude (63%)4, but concentrated in heavily burned regions and occurs only during burning season. Effects of both emissions are not additive since a larger flux of emissions causes greater deposition. The resulting further impacts of land-use change on regional hydrometeorology are also explored

Climate driven range divergence among host species affects range-wide patterns of parasitism

Directory of Open Access Journals (Sweden)

Richard E. Feldman

2017-01-01

Full Text Available Species interactions like parasitism influence the outcome of climate-driven shifts in species ranges. For some host species, parasitism can only occur in that part of its range that overlaps with a second host species. Thus, predicting future parasitism may depend on how the ranges of the two hosts change in relation to each other. In this study, we tested whether the climate driven species range shift of Odocoileus virginianus (white-tailed deer accounts for predicted changes in parasitism of two other species from the family Cervidae, Alces alces (moose and Rangifer tarandus (caribou, in North America. We used MaxEnt models to predict the recent (2000 and future (2050 ranges (probabilities of occurrence of the cervids and a parasite Parelaphostrongylus tenuis (brainworm taking into account range shifts of the parasite’s intermediate gastropod hosts. Our models predicted that range overlap between A. alces/R. tarandus and P. tenuis will decrease between 2000 and 2050, an outcome that reflects decreased overlap between A. alces/R. tarandus and O. virginianus and not the parasites, themselves. Geographically, our models predicted increasing potential occurrence of P. tenuis where A. alces/R. tarandus are likely to decline, but minimal spatial overlap where A. alces/R. tarandus are likely to increase. Thus, parasitism may exacerbate climate-mediated southern contraction of A. alces and R. tarandus ranges but will have limited influence on northward range expansion. Our results suggest that the spatial dynamics of one host species may be the driving force behind future rates of parasitism for another host species.

Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions

Science.gov (United States)

Isaksen, Ivar S.A.; Gauss, Michael; Myhre, Gunnar; Walter Anthony, Katey M.; Ruppel, Carolyn

2011-01-01

The magnitude and feedbacks of future methane release from the Arctic region are unknown. Despite limited documentation of potential future releases associated with thawing permafrost and degassing methane hydrates, the large potential for future methane releases calls for improved understanding of the interaction of a changing climate with processes in the Arctic and chemical feedbacks in the atmosphere. Here we apply a “state of the art” atmospheric chemistry transport model to show that large emissions of CH4 would likely have an unexpectedly large impact on the chemical composition of the atmosphere and on radiative forcing (RF). The indirect contribution to RF of additional methane emission is particularly important. It is shown that if global methane emissions were to increase by factors of 2.5 and 5.2 above current emissions, the indirect contributions to RF would be about 250% and 400%, respectively, of the RF that can be attributed to directly emitted methane alone. Assuming several hypothetical scenarios of CH4 release associated with permafrost thaw, shallow marine hydrate degassing, and submarine landslides, we find a strong positive feedback on RF through atmospheric chemistry. In particular, the impact of CH4 is enhanced through increase of its lifetime, and of atmospheric abundances of ozone, stratospheric water vapor, and CO2 as a result of atmospheric chemical processes. Despite uncertainties in emission scenarios, our results provide a better understanding of the feedbacks in the atmospheric chemistry that would amplify climate warming.

Reducing greenhouse gas emissions: Lessons from state climate action plans

Energy Technology Data Exchange (ETDEWEB)

Pollak, Melisa, E-mail: mpollak@umn.edu [Humphrey Institute of Public Affairs, University of Minnesota, 301 19th Avenue South, Minneapolis, MN 55455 (United States); Meyer, Bryn, E-mail: meye1058@umn.edu [Humphrey Institute of Public Affairs, University of Minnesota, 301 19th Avenue South, Minneapolis, MN 55455 (United States); Wilson, Elizabeth, E-mail: ewilson@umn.edu [Humphrey Institute of Public Affairs, University of Minnesota, 301 19th Avenue South, Minneapolis, MN 55455 (United States)

2011-09-15

We examine how state-level factors affect greenhouse gas (GHG) reduction policy preference across the United States by analyzing climate action plans (CAPs) developed in 11 states and surveying the CAP advisory group members. This research offers insights into how states approach the problem of choosing emissions-abatement options that maximize benefits and minimize costs, given their unique circumstances and the constellation of interest groups with power to influence state policy. The state CAPs recommended ten popular GHG reduction strategies to accomplish approximately 90% of emissions reductions, but they recommended these popular strategies in different proportions: a strategy that is heavily relied on in one state's overall portfolio may play a negligible role in another state. This suggests that any national policy to limit GHG emissions should encompass these key strategies, but with flexibility to allow states to balance their implementation for the state's unique geographic, economic, and political circumstances. Survey results strongly support the conclusion that decisions regarding GHG reductions are influenced by the mix of actors at the table. Risk perception is associated with job type for all strategies, and physical and/or geographic factors may underlie the varying reliance on certain GHG reduction strategies across states. - Highlights: > This study analyzed climate action plans from 12 states and surveyed the advisory group members. > Ten strategies supply 90% of recommended emission reductions, but states weigh them differently. > Advisory group members perceived different opportunities and risks in the top-ten strategies. > Both geographic and socio-political factors may underlie the varying reliance on certain strategies. > Cost, business practices and consumer behavior were ranked as the top barriers to reducing emissions.

Reducing greenhouse gas emissions: Lessons from state climate action plans

International Nuclear Information System (INIS)

Pollak, Melisa; Meyer, Bryn; Wilson, Elizabeth

2011-01-01

We examine how state-level factors affect greenhouse gas (GHG) reduction policy preference across the United States by analyzing climate action plans (CAPs) developed in 11 states and surveying the CAP advisory group members. This research offers insights into how states approach the problem of choosing emissions-abatement options that maximize benefits and minimize costs, given their unique circumstances and the constellation of interest groups with power to influence state policy. The state CAPs recommended ten popular GHG reduction strategies to accomplish approximately 90% of emissions reductions, but they recommended these popular strategies in different proportions: a strategy that is heavily relied on in one state's overall portfolio may play a negligible role in another state. This suggests that any national policy to limit GHG emissions should encompass these key strategies, but with flexibility to allow states to balance their implementation for the state's unique geographic, economic, and political circumstances. Survey results strongly support the conclusion that decisions regarding GHG reductions are influenced by the mix of actors at the table. Risk perception is associated with job type for all strategies, and physical and/or geographic factors may underlie the varying reliance on certain GHG reduction strategies across states. - Highlights: → This study analyzed climate action plans from 12 states and surveyed the advisory group members. → Ten strategies supply 90% of recommended emission reductions, but states weigh them differently. → Advisory group members perceived different opportunities and risks in the top-ten strategies. → Both geographic and socio-political factors may underlie the varying reliance on certain strategies. → Cost, business practices and consumer behavior were ranked as the top barriers to reducing emissions.

Climate Benefits of Potential Avoided Emissions from Forest Conversion Diminished by Albedo Warming: Comprehensive, Data-Driven Assessment for the US and Beyond

Science.gov (United States)

Williams, C. A.; Gu, H.; Jiao, T.

2017-12-01

Avoided deforestation is a leading pathway for climate change mitigation, featuring prominently in many country's Intended Nationally Determined Contributions, but its climate benefits remain contested, in part because of reports of large offsetting effects in some regions of the world. It is well known that avoiding forest to non-forest conversion prevents forest carbon release, and sustains forest carbon uptake, but also increases albedo thus diminishing the potency of this mitigation strategy. While the mechanisms are known, their relative importance and the resulting climate benefit remain unclear. This is in part due to a lack of quantitative assessments documenting geographic variation in rates of forest conversion, associated carbon emissions, resulting radiative forcing, and the magnitude of simultaneous albedo offsets. This study (i) quantifies the current rate of forest conversion and carbon release in the United States with Landsat remote sensing and a carbon assessment framework, and (ii) compares this to quantitative estimates of the radiative forcing from the corresponding albedo change. Albedo radiative forcing is assessed with a recently-generated, global atlas of land-cover-specific albedos derived from a fusion of MODIS and Landsat reflectances, combined with snow cover and solar radiation datasets. We document the degree to which albedo warming offsets carbon cooling from contemporary forest conversions taking place in different regions of the United States and identify the underlying drivers of spatial variability. We then extend this to other regions of the world where forests are under threat and where avoided deforestation is viewed as a primary tool for climate mitigation. Results shed light on the, at times contentious, debate about the efficacy of forest protection as a mitigation mechanism.

Key Senators Issue Call for `Meaningful' Climate Legislation

Science.gov (United States)

Showstack, Randy

With the U.S. Senate currently considering national energy legislation, Senators John McCain (R-Arizona) and Joseph Lieberman (D-Connecticut) plan to offer a modified version of their bipartisan, proposed Climate Stewardship Act of 2003 (S. 139) as an amendment. The amendment would establish a market driven system of greenhouse gas tradeable allowances to reduce emission. It would also provide for a program of scientific research on abrupt climate change in order to identify and understand past instances of abrupt change; and would establish a national greenhouse gas data base.

High estimates of supply constrained emissions scenarios for long-term climate risk assessment

International Nuclear Information System (INIS)

Ward, James D.; Mohr, Steve H.; Myers, Baden R.; Nel, Willem P.

2012-01-01

The simulated effects of anthropogenic global warming have become important in many fields and most models agree that significant impacts are becoming unavoidable in the face of slow action. Improvements to model accuracy rely primarily on the refinement of parameter sensitivities and on plausible future carbon emissions trajectories. Carbon emissions are the leading cause of global warming, yet current considerations of future emissions do not consider structural limits to fossil fuel supply, invoking a wide range of uncertainty. Moreover, outdated assumptions regarding the future abundance of fossil energy could contribute to misleading projections of both economic growth and climate change vulnerability. Here we present an easily replicable mathematical model that considers fundamental supply-side constraints and demonstrate its use in a stochastic analysis to produce a theoretical upper limit to future emissions. The results show a significant reduction in prior uncertainty around projected long term emissions, and even assuming high estimates of all fossil fuel resources and high growth of unconventional production, cumulative emissions tend to align to the current medium emissions scenarios in the second half of this century. This significant finding provides much-needed guidance on developing relevant emissions scenarios for long term climate change impact studies. - Highlights: ► GHG emissions from conventional and unconventional fossil fuels modelled nationally. ► Assuming worst-case: large resource, high growth, rapid uptake of unconventional. ► Long-term cumulative emissions align well with the SRES medium emissions scenario. ► High emissions are unlikely to be sustained through the second half of this century. ► Model designed to be easily extended to test other scenarios e.g. energy shortages.

Confronting the climate change challenge: discussing the role of rural India under cumulative emission budget approach

International Nuclear Information System (INIS)

Kaechele, Harald; Amjath-Babu, T.S.; Kutter, Thomas; Specht, Kathrin; Nautiyal, Sunil; Müller, Klaus; Raju, K.V.

2011-01-01

Current global climate policy architecture does not aim at stabilizing the greenhouse gases concentration in the atmosphere that may achieve the proclaimed 2 °C guard rail. An alternative approach that targets on limiting the global cumulative emission to accomplish such an outcome is put forward by German Advisory Board of Global Change (WBGU). This research work further elaborates the approach and its flexibility instrument i.e. carbon trading. As the approach visualises sharing of the carbon budget (750Gt CO 2 ) equally to every human being (2.7 t CO 2 per capita), India is the country with largest tradable surplus reflecting its low emission per capita and large population. The research work further analyzes the emission profile of rural India and the significance of its future emission pathways within the proposed framework. It also shows how low carbon development in India can assist in cost effective decarbonization of industrialized countries and mitigation of climate change, given a global climate treaty based on the WBGU approach.

The impact of climate change and emissions control on future ozone levels: Implications for human health.

Science.gov (United States)

Stowell, Jennifer D; Kim, Young-Min; Gao, Yang; Fu, Joshua S; Chang, Howard H; Liu, Yang

2017-11-01

Overwhelming evidence has shown that, from the Industrial Revolution to the present, human activities influence ground-level ozone (O 3 ) concentrations. Past studies demonstrate links between O 3 exposure and health. However, knowledge gaps remain in our understanding concerning the impacts of climate change mitigation policies on O 3 concentrations and health. Using a hybrid downscaling approach, we evaluated the separate impact of climate change and emission control policies on O 3 levels and associated excess mortality in the US in the 2050s under two Representative Concentration Pathways (RCPs). We show that, by the 2050s, under RCP4.5, increased O 3 levels due to combined climate change and emission control policies, could contribute to an increase of approximately 50 premature deaths annually nationwide in the US. The biggest impact, however, is seen under RCP8.5, where rises in O 3 concentrations are expected to result in over 2,200 additional premature deaths annually. The largest increases in O 3 are seen in RCP8.5 in the Northeast, the Southeast, the Central, and the West regions of the US. Additionally, when O 3 increases are examined by climate change and emissions contributions separately, the benefits of emissions mitigation efforts may significantly outweigh the effects of climate change mitigation policies on O 3 -related mortality. Copyright © 2017 Elsevier Ltd. All rights reserved.

Disentangling the effects of CO2 and short-lived climate forcer mitigation

NARCIS (Netherlands)

Rogelj, J.; Schaeffer, M.; Meinshausen, M.; Shindell, D.T.; Hare, W.; Klimont, Z.; Velders, G.J.M.; Amann, M.; Schellnhuber, H.J.

2014-01-01

Anthropogenic global warming is driven by emissions of a wide variety of radiative forcers ranging from very short-lived climate forcers (SLCFs), like black carbon, to very long-lived, like CO2. These species are often released from common sources and are therefore intricately linked. However, for

The distributional effects of emissions taxation in Brazil and their implications for climate policy

International Nuclear Information System (INIS)

Silva Freitas, Lucio Flavio da; Santana Ribeiro, Luiz Carlos de; Barreiro de Souza, Kênia; Hewings, Geoffrey John Dennis

2016-01-01

The emission of greenhouse gases (GHG) generated by human activity is a major cause of global warming and climate change. There is considerable debate about the choice of the best mechanism to reduce emissions under a climate policy. The aim of this paper is to measure the impact of a policy of taxing GHG emissions on the Brazilian economy as a whole and on different household groups based on income levels in 2009. The following databases were used: Supply and Use Tables, Household Budget Survey, National Household Sample Survey and emissions data from the Brazilian Ministry of Science and Technology and Innovation. A price system from a national input–output model that incorporates the intensity of GHG emissions is used, as well as a consumption vector broken down into ten representative households with different income levels. The main results indicate that this taxation system was slightly regressive and had a small negative impact on output. There were, however, significant emissions reductions. - Highlights: • We measure the distributive impact of a taxation policy of GHG emissions in Brazil. • Poorest households have the highest expenditure emissions coefficient. • The poorest households are most affected by both reducing consumption and labor income. • Overall, the taxation was slightly regressive and had a small negative impact on output.

Climate-driven ichthyoplankton drift model predicts growth of top predator young.

Directory of Open Access Journals (Sweden)

Mari S Myksvoll

Full Text Available Climate variability influences seabird population dynamics in several ways including access to prey near colonies during the critical chick-rearing period. This study addresses breeding success in a Barents Sea colony of common guillemots Uria aalge where trophic conditions vary according to changes in the northward transport of warm Atlantic Water. A drift model was used to simulate interannual variations in transport of cod Gadus morhua larvae along the Norwegian coast towards their nursery grounds in the Barents Sea. The results showed that the arrival of cod larvae from southern spawning grounds had a major effect on the size of common guillemot chicks at fledging. Furthermore, the fraction of larvae from the south was positively correlated to the inflow of Atlantic Water into the Barents Sea thus clearly demonstrating the mechanisms by which climate-driven bottom-up processes influence interannual variations in reproductive success in a marine top predator.

Quantifying Anthropogenic Dust Emissions

Science.gov (United States)

Webb, Nicholas P.; Pierre, Caroline

2018-02-01

Anthropogenic land use and land cover change, including local environmental disturbances, moderate rates of wind-driven soil erosion and dust emission. These human-dust cycle interactions impact ecosystems and agricultural production, air quality, human health, biogeochemical cycles, and climate. While the impacts of land use activities and land management on aeolian processes can be profound, the interactions are often complex and assessments of anthropogenic dust loads at all scales remain highly uncertain. Here, we critically review the drivers of anthropogenic dust emission and current evaluation approaches. We then identify and describe opportunities to: (1) develop new conceptual frameworks and interdisciplinary approaches that draw on ecological state-and-transition models to improve the accuracy and relevance of assessments of anthropogenic dust emissions; (2) improve model fidelity and capacity for change detection to quantify anthropogenic impacts on aeolian processes; and (3) enhance field research and monitoring networks to support dust model applications to evaluate the impacts of disturbance processes on local to global-scale wind erosion and dust emissions.

Impact of plastic mulching on nitrous oxide emissions in China's arid agricultural region under climate change conditions

Science.gov (United States)

Yu, Yongxiang; Tao, Hui; Jia, Hongtao; Zhao, Chengyi

2017-06-01

The denitrification-decomposition (DNDC) model is a useful tool for integrating the effects of agricultural practices and climate change on soil nitrous oxide (N2O) emissions from agricultural ecosystems. In this study, the DNDC model was evaluated against observations and used to simulate the effect of plastic mulching on soil N2O emissions and crop growth. The DNDC model performed well in simulating temporal variations in N2O emissions and plant growth during the observation period, although it slightly underestimated the cumulative N2O emissions, and was able to simulate the effects of plastic mulching on N2O emissions and crop yield. Both the observations and simulations demonstrated that the application of plastic film increased cumulative N2O emissions and cotton lint yield compared with the non-mulched treatment. The sensitivity test showed that the N2O emissions and lint yield were sensitive to changes in climate and management practices, and the application of plastic film made the N2O emissions and lint yield less sensitive to changes in temperature and irrigation. Although the simulations showed that the beneficial impacts of plastic mulching on N2O emissions were not gained under high fertilizer and irrigation scenarios, our simulations suggest that the application of plastic film effectively reduced soil N2O emissions while promoting yields under suitable fertilizer rates and irrigation. Compared with the baseline scenario, future climate change significantly increased N2O emissions by 15-17% without significantly influencing the lint yields in the non-mulched treatment; in the mulched treatment, climate change significantly promoted the lint yield by 5-6% and significantly reduced N2O emissions by 14% in the RCP4.5 and RCP8.5 scenarios. Overall, our results demonstrate that the application of plastic film is an efficient way to address increased N2O emissions and simultaneously enhance crop yield in the future.

Extended Challenges for the EU's Climate and Energy Policy

International Nuclear Information System (INIS)

Haslauer, F.

2015-01-01

Market-driven climate and energy policies are far more effective than regulation-driven policies. It is time for the EU to rethink its energy strategy. The world is in the throes of a global energy transition as countries seek to meet rising demand by fundamentally changing their energy sectors. Global energy demand is expected to increase by 1.4 percent through 2030, with demand for electricity (a renewable) rising by more than 2 percent during this time period. The European Union has been front and center in this energy transition, seeking to meet three climate and energy targets by 2020: (1) reduce CO2 emissions, (2) increase renewables, and (3) become more energy efficient. Most countries are on track to meet the first two targets but meeting the third one has proved to be more difficult. This is largely because there is no single European power market. Energy policies and regulations are still driven by individual nations. If this continues, the EU energy transition will be costly - prices will shoot up and global competitiveness will suffer. It's time for the EU to work as one large entity and adopt market-driven policies. The advantages include a smoother energy transition in a growing economy, ability to leverage size for more competitive energy costs, and lower prices for consumers. In an ideal scenario, there is one overriding EU target for reducing CO2 emissions, and then the other two - renewables and energy efficiency - act as levers to meet that target. Essentially, the market decides which solutions are the most efficient. A market-driven energy strategy is funded from a CO2-emissions certificate market - to send the right price signals - or a CO2 tax to allocate costs to CO2 emissions. Rather than concentrating funds on feed in tariffs, funds are geared toward improving energy efficiency, research and development of renewables and running pilot programs. In this way, the EU 'incentivizes' innovation and funding is far less than what

Greenhouse gas emissions trading and complementary policies. Developing a smart mix for ambitious climate policies

Energy Technology Data Exchange (ETDEWEB)

Matthes, Felix C.

2010-06-15

A debate has - most notably as a result of the introduction of fixed caps within the framework of emissions trading - been raised about the need for using additional instruments of climate and energy policy. A common line of argument is that the targets set within the emissions trading scheme are going to be met with a high degree of certainty, and flexibility among the regulated stakeholders will lead to market-based discovery processes. Additional instruments would only generate additional costs and would therefore have to be rejected. However, closer analysis of these fundamental arguments shows that they are constructed on a very high level of abstraction and sometimes rely on strongly simplifying or idealising assumptions. Their theoretical assumptions are, at least in part, very questionable and do not correspond to conditions in the real world for climate and energy policy. At the same time the debate about policy instruments cannot be held autonomously of the specific context of the problem at hand. In this sense the very extensive (complete) and above all effective decarbonisation of the economies of industrialised countries in a comparatively short time frame is the key basic condition for the analysis, assessment and design of the climate policy mix. Essentially, the question is what the best instruments are for purging the whole economic system almost entirely of CO{sub 2} emissions within a period of only forty years. The introduction of emissions trading schemes for greenhouse gases in an increasing number of OECD countries undoubtedly constitutes an important landmark of climate policy. They: - provide a high degree of certainty in terms of meeting targets; - create, on the basis of a standardised price signal, a clearing mechanism for the broad spectrum of emission reduction options close to the market, at least in the short to medium term; and - represent, by means of linking, an interesting option in terms of the globalisation of climate policy

Strategies for implementing Climate Smart Agriculture and creating marketable Greenhouse emission reduction credits, for small scale rice farmers in Asia

Science.gov (United States)

Ahuja, R.; Kritee, K.; Rudek, J.; Van Sanh, N.; Thu Ha, T.

2014-12-01

Industrial agriculture systems, mostly in developed and some emerging economies, are far different from the small holder farms that dot the landscapes in Asia and Africa. At Environmental Defense Fund, along with our partners from non-governmental, corporate, academic and government sectors and farmers, we have worked actively in India and Vietnam for the last four years to better understand how small scale farmers working on rice paddy (and other upland crops) cultivation can best deal with climate change. Some of the questions we have tried to answer are: What types of implementable best practices, both old and new, on small farm systems lend themselves to improved yields, farm incomes, climate resilience and mitigation? Can these practices be replicated everywhere or is the change more landscape and people driven? What are the institutional, cultural, financial and risk-perception related barriers that prevent scaling up of these practices? How do we innovate and overcome these barriers? The research community needs to work more closely together and leverage multiple scientific, economic and policy disciplines to fully answer these questions. In the case of small farm systems, we find that it helps to follow certain steps if the climate-smart (or low carbon) farming programs are to succeed and the greenhouse credits generated are to be marketed: Demographic data collection and plot demarcation Farmer networks and diaries Rigorous baseline determination via surveys Alternative practice determination via consultation with local universities/experts Measurements on representative plots for 3-4 years (including GHG emissions, yields, inputs, economic and environmental savings) to help calibrate biogeochemical models and/or calculate regional emission factors. Propagation of alternative practices across the landscape via local NGOs/governments Recording of parameters necessary to extrapolate representative plot GHG emission reductions to all farmers in a given

Climate change impacts on hydrology and water resources

Directory of Open Access Journals (Sweden)

Fred Fokko Hattermann

2015-04-01

Full Text Available Aim of our study is to quantify the impacts of climate change on hydrology in the large river basins in Germany (Rhine, Elbe, Danube, Weser and Ems and thereby giving the range of impact uncertainty created by the most recent regional climate projections. The study shows mainly results for the A1B SRES (Special Report on Emission Scenario scenario by comparing the reference period 1981–2010 and the scenario periods 2031–2060 and 2061–2090 and using climate projections of a combination of 4 Global Climate Models (GCMs and 12 Regional Climate Models (RCMs as climate driver. The outcome is compared against impacts driven by a more recent RCP (Representative Emission Pathways scenario by using data of a statistical RCM. The results indicate that more robust conclusions can be drawn for some river basins, especially the Rhine and Danube basins, while diversity of results leads to higher uncertainty in the other river basins. The results also show that hydrology is very sensitive to changes in climate and effects of a general increase in precipitation can even be over-compensated by an increase in evapotranspiration. The decrease of runoff in late summer shown in most results can be an indicator for more pronounced droughts under scenario conditions.

Induced absorption and stimulated emission in a driven two-level atom

International Nuclear Information System (INIS)

Mavroyannis, C.

1992-01-01

We have considered the induced processes that occur in a driven two-level atom, where a laser photon is absorbed and emitted by the ground and by the excited states of the atom, respectively. In the low-intensity limit of the laser field, the induced spectra arising when a laser photon is absorbed by the ground state of the atom consist of two peaks describing induced absorption and stimulated-emission processes, respectively, where the former prevails over the latter. Asymmetry of the spectral lines occurs at off-resonance and its extent depends on the detuning of the laser field. The physical. process where a laser photon is emitted by the excited state is the reverse of that arising from the absorption of a laser photon by the ground state of the atom. The former differs from the latter in that the emission of a laser photon by the excited state occurs in the low frequency regime and that the stimulated-emission process prevails over that of the induced absorption. In this case, amplification of ultrashort pulses is likely to occur without the need of population inversion between the optical transitions. The computed spectra are graphically presented and discussed. (author)

Assessing “Dangerous Climate Change”: Required Reduction of Carbon Emissions to Protect Young People, Future Generations and Nature

Science.gov (United States)

Hansen, James; Kharecha, Pushker; Sato, Makiko; Masson-Delmotte, Valerie; Ackerman, Frank; Beerling, David J.; Hearty, Paul J.; Hoegh-Guldberg, Ove; Hsu, Shi-Ling; Parmesan, Camille; Rockstrom, Johan; Rohling, Eelco J.; Sachs, Jeffrey; Smith, Pete; Steffen, Konrad; Van Susteren, Lise; von Schuckmann, Karina; Zachos, James C.

2013-01-01

We assess climate impacts of global warming using ongoing observations and paleoclimate data. We use Earth’s measured energy imbalance, paleoclimate data, and simple representations of the global carbon cycle and temperature to define emission reductions needed to stabilize climate and avoid potentially disastrous impacts on today’s young people, future generations, and nature. A cumulative industrial-era limit of ∼500 GtC fossil fuel emissions and 100 GtC storage in the biosphere and soil would keep climate close to the Holocene range to which humanity and other species are adapted. Cumulative emissions of ∼1000 GtC, sometimes associated with 2°C global warming, would spur “slow” feedbacks and eventual warming of 3–4°C with disastrous consequences. Rapid emissions reduction is required to restore Earth’s energy balance and avoid ocean heat uptake that would practically guarantee irreversible effects. Continuation of high fossil fuel emissions, given current knowledge of the consequences, would be an act of extraordinary witting intergenerational injustice. Responsible policymaking requires a rising price on carbon emissions that would preclude emissions from most remaining coal and unconventional fossil fuels and phase down emissions from conventional fossil fuels. PMID:24312568

An alternative to the global warming potential for comparing climate impacts of emissions of greenhouse gases

International Nuclear Information System (INIS)

Shine, Keith P.; Fuglestvedt, Jan S.; Stuber, Nicola

2003-01-01

The global warming potential (GWP) is used within the Kyoto Protocol to the United Nations Framework Convention on Climate Change as a metric for weighting the climate impact of emissions of different greenhouse gases. The GQP has been subject at many criticism because of its formulation but nevertheless it has retained some favour because of the simplicity of this design and application and its transparency compared to proposed alternatives. Here a new metric which we call the Global Temperature Change Potential (GTP) is proposed which is based on a simple analytical climate model that represents the temperature change as a given time due to either a pulse emission of a gas or a sustained emission change relative to a similar emission change of carbon dioxide. The GTP for a pulse emission illustrates that the GWP does not represent well the relative temperature response; however, the GWP is shown to be very close to the GTP for a sustained emission change for time horizons of 100 years or more. The new metric retains the advantage of the GWP in terms of transparency and the relatively small number of input parameters required for calculation. However, it has an enhanced relevance as it is further down the cause-effect chain of the impacts of greenhouse gases emissions. The GTP for a sustained emission appears to be robust to a number of uncertainties and simplifications in its derivation and may be an attractive alternative to the GWP. (Author)

Field emission device driven by self-powered contact-electrification: Simulation and experimental analysis

Science.gov (United States)

Chen, Xiangyu; Jiang, Tao; Sun, Zhuo; Ou-Yang, Wei

2015-09-01

A self-powered field emission device (FED) driven by a single-electrode tribo-electric nanogenerator (TENG) is demonstrated. The mechanical motion works as both a power supply to drive the FED and a control unit to regulate the amount of emitted electrons. By using the Fowler-Nordheim equation and Kirchhoff laws, a theoretical model of this self-powered FED is proposed, and accordingly the real-time output characteristics of the device are systematically investigated. It is found that the motion distance of the TENG controls switch-on of the FED and determines the charge amount for emission, while the motion velocity regulates the amplitude of emission current. The minimum contact area for the TENG to generate field emission is about 9 cm2, which can be improved by optimizing FED structure and the tribo-materials of TENG. The demonstrated concept of this self-powered FED as well as the proposed physical analysis can serve as guidance for further applications of FED in such fields of self-powered electronics and soft electronics.

Field emission device driven by self-powered contact-electrification: Simulation and experimental analysis

Energy Technology Data Exchange (ETDEWEB)

Chen, Xiangyu, E-mail: chenxiangyu@binn.cas.cn, E-mail: ouyangwei@phy.ecnu.edu.cn; Jiang, Tao [Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing 100083 (China); Sun, Zhuo; Ou-Yang, Wei, E-mail: chenxiangyu@binn.cas.cn, E-mail: ouyangwei@phy.ecnu.edu.cn [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062 (China)

2015-09-14

A self-powered field emission device (FED) driven by a single-electrode tribo-electric nanogenerator (TENG) is demonstrated. The mechanical motion works as both a power supply to drive the FED and a control unit to regulate the amount of emitted electrons. By using the Fowler-Nordheim equation and Kirchhoff laws, a theoretical model of this self-powered FED is proposed, and accordingly the real-time output characteristics of the device are systematically investigated. It is found that the motion distance of the TENG controls switch-on of the FED and determines the charge amount for emission, while the motion velocity regulates the amplitude of emission current. The minimum contact area for the TENG to generate field emission is about 9 cm{sup 2}, which can be improved by optimizing FED structure and the tribo-materials of TENG. The demonstrated concept of this self-powered FED as well as the proposed physical analysis can serve as guidance for further applications of FED in such fields of self-powered electronics and soft electronics.

Field emission device driven by self-powered contact-electrification: Simulation and experimental analysis

International Nuclear Information System (INIS)

Chen, Xiangyu; Jiang, Tao; Sun, Zhuo; Ou-Yang, Wei

2015-01-01

A self-powered field emission device (FED) driven by a single-electrode tribo-electric nanogenerator (TENG) is demonstrated. The mechanical motion works as both a power supply to drive the FED and a control unit to regulate the amount of emitted electrons. By using the Fowler-Nordheim equation and Kirchhoff laws, a theoretical model of this self-powered FED is proposed, and accordingly the real-time output characteristics of the device are systematically investigated. It is found that the motion distance of the TENG controls switch-on of the FED and determines the charge amount for emission, while the motion velocity regulates the amplitude of emission current. The minimum contact area for the TENG to generate field emission is about 9 cm 2 , which can be improved by optimizing FED structure and the tribo-materials of TENG. The demonstrated concept of this self-powered FED as well as the proposed physical analysis can serve as guidance for further applications of FED in such fields of self-powered electronics and soft electronics

Energy climate study. Energy assessment, Greenhouse gas emission assessment, Analysis of vulnerability to climate change, Courses of mitigation and adaptation actions. Full report + Appendices + Restitution of the Energy-Climate Study, September 17, 2012

International Nuclear Information System (INIS)

2012-01-01

After a brief presentation of Le Mans region, a presentation of the study (context, scope, methodology), and a recall of challenges related to energy and to climate, this study reports a situational analysis and a discussion of development perspectives for energy production on the concerned territory, an assessment of energy consumptions and of greenhouse gas emissions by the different sectors, and a study of territory vulnerability to climate change (methodology, territory characteristics, climate scenarios, vulnerability assessment). It discusses lessons learned from energy and greenhouse gas emission assessments (social-economic stakes, territory strengths and weaknesses, perspectives for action). It discusses the implementation of these issues within a territorial planning document, and the perspective of elaboration of a territorial climate energy plan. An appendix reports an assessment of the potential of development of the different renewable energies (hydroelectric, solar photovoltaic and thermal, wind, wood, methanization, and other processes like waste valorisation, geothermal, and heat networks). Another appendix reports the precise assessment of greenhouse gas emissions on the territory. The next appendix proposes detailed descriptions of scenarios for the implementation of the issue of greenhouse gas emissions within the territorial planning document. The last appendix contains Power Point presentations of the study

Import of combustible waste and its impact on emissions of climate gases

Energy Technology Data Exchange (ETDEWEB)

Haraldsson, Maarten; Sundberg, Johan (Profu, Moelndal (Sweden))

2010-07-01

Import of combustible waste for waste incineration in Sweden has increased over the last decade and prognosis show that importation will increase even further in the future. The reason for the projected increase is that many new incineration facilities are being built and several of those plan to use a portion of imported combustible waste as fuel. From an environmental perspective import of waste is controversial and some argue that the import short be restricted. Because of this controversial aspect it is essential to conduct a comprehensive analysis of the environmental impacts of the importation of combustible waste to Swedish incineration facilities. This project is a study of the impact of the import of combustible waste on climate emissions. This is a system analysis study which included both direct as well as indirect emissions from the activity of importation of combustible waste. Direct emissions occur from the incineration of waste while indirect emissions occur in systems that interact with the incineration facility. These systems are: transport of waste, alternative waste treatment, alternative electricity production and alternative heat production in the district heating system which the incineration facility is connected with. From the perspective of a system analysis the import of combustible waste to incineration leads to the following consequences regarding emissions of climate gases: - The imported waste is used as fuel in the incineration facility which generates heat and electricity. During the combustion process climate gases are being emitted - As the combustible waste is being imported it has to be transported from the country of origin to the incineration facility. The vehicle used for the transport is emitting climate gases - By importing combustible waste an alternative treatment method in the country of origin is avoided by that country. Emissions from the alternative treatment method are thereby avoided - Import of combustible waste

Reversible and irreversible impacts of greenhouse gas emissions in multi-century projections with the NCAR global coupled carbon cycle-climate model

Energy Technology Data Exchange (ETDEWEB)

Froelicher, Thomas L.; Joos, Fortunat [University of Bern, Climate and Environmental Physics, Physics Institute, Bern (Switzerland); University of Bern, Oeschger Centre for Climate Change Research, Bern (Switzerland)

2010-12-15

The legacy of historical and the long-term impacts of 21st century greenhouse gas emissions on climate, ocean acidification, and carbon-climate feedbacks are investigated with a coupled carbon cycle-climate model. Emission commitment scenarios with zero emissions after year 2100 and 21st century emissions of 1,800, 900, and 0 gigatons of carbon are run up to year 2500. The reversibility and irreversibility of impacts is quantified by comparing anthropogenically-forced regional changes with internal, unforced climate variability. We show that the influence of historical emissions and of non-CO{sub 2} agents is largely reversible on the regional scale. Forced changes in surface temperature and precipitation become smaller than internal variability for most land and ocean grid cells in the absence of future carbon emissions. In contrast, continued carbon emissions over the 21st century cause irreversible climate change on centennial to millennial timescales in most regions and impacts related to ocean acidification and sea level rise continue to aggravate for centuries even if emissions are stopped in year 2100. Undersaturation of the Arctic surface ocean with respect to aragonite, a mineral form of calcium carbonate secreted by marine organisms, is imminent and remains widespread. The volume of supersaturated water providing habitat to calcifying organisms is reduced from preindustrial 40 to 25% in 2100 and to 10% in 2300 for the high emission case. We conclude that emission trading schemes, related to the Kyoto Process, should not permit trading between emissions of relatively short-lived agents and CO{sub 2} given the irreversible impacts of anthropogenic carbon emissions. (orig.)

Regional air quality management aspects of climate change: impact of climate mitigation options on regional air emissions.

Science.gov (United States)

Rudokas, Jason; Miller, Paul J; Trail, Marcus A; Russell, Armistead G

2015-04-21

We investigate the projected impact of six climate mitigation scenarios on U.S. emissions of carbon dioxide (CO2), sulfur dioxide (SO2), and nitrogen oxides (NOX) associated with energy use in major sectors of the U.S. economy (commercial, residential, industrial, electricity generation, and transportation). We use the EPA U.S. 9-region national database with the MARKet Allocation energy system model to project emissions changes over the 2005 to 2050 time frame. The modeled scenarios are two carbon tax, two low carbon transportation, and two biomass fuel choice scenarios. In the lower carbon tax and both biomass fuel choice scenarios, SO2 and NOX achieve reductions largely through pre-existing rules and policies, with only relatively modest additional changes occurring from the climate mitigation measures. The higher carbon tax scenario projects greater declines in CO2 and SO2 relative to the 2050 reference case, but electricity sector NOX increases. This is a result of reduced investments in power plant NOX controls in earlier years in anticipation of accelerated coal power plant retirements, energy penalties associated with carbon capture systems, and shifting of NOX emissions in later years from power plants subject to a regional NOX cap to those in regions not subject to the cap.

Modelling marine community responses to climate-driven species redistribution to guide monitoring and adaptive ecosystem-based management

NARCIS (Netherlands)

Marzloff, Martin Pierre; Melbourne-Thomas, Jessica; Hamon, Katell G.; Hoshino, Eriko; Jennings, Sarah; Putten, Van Ingrid E.; Pecl, Gretta T.

2016-01-01

As a consequence of global climate-driven changes, marine ecosystems are experiencing polewards redistributions of species – or range shifts – across taxa and throughout latitudes worldwide. Research on these range shifts largely focuses on understanding and predicting changes in the distribution of

Restoring Tides to Avoid Methane Emissions in Degraded Wetlands: A Potent and Untapped Climate Intervention

Science.gov (United States)

Kroeger, K. D.; Crooks, S.; Moseman-Valtierra, S.; Tang, J.

2016-12-01

To date, activity related to carbon (C) management in coastal marine ecosystems (sometimes referred to as "Blue Carbon") has been concerned primarily with preserving existing C stocks or creating new wetlands to increase CO2 uptake and sequestration. Here we show that the globally-widespread occurrence of hydrologically-altered, degraded wetlands, and associated enhanced GHG emissions, presents an opportunity to reduce an anthropogenic GHG emission through restoration. We model the climatic forcing associated with carbon sinks in natural wetlands and with GHG emissions in altered and degraded wetlands, as well as compile geographic data on tidal restrictions to show that substantial methane (CH4) and CO2 emission reductions can be achieved through restoration of saline tidal flows in diked, impounded and tidally-restricted coastal wetlands. Despite high rates of carbon storage in coastal ecosystems, tidal restoration has dramatically greater potential per unit area as a climate intervention than most other ecosystem management actions. We argue that such emissions reductions represent avoided anthropogenic emissions, equivalent in concept to reduced fossil fuel emissions. Once the emissions have been avoided, the benefit of that action cannot be eliminated, even if emissions resume in the future due to degradation of the ecosystem. The avoided emissions therefore have inherent "permanence", obviating concerns associated with vulnerability of C stocks in land-use based interventions that enhance C sequestration in wood or soil. Further, emissions reductions are likely to be rapid, and given the high radiative efficiency of avoided CH4, wetland tidal restorations can provide near-term climate benefit. The U.S. has recently initiated an effort to include coastal wetlands in the Inventory of U.S. Greenhouse Gas Emissions and Sinks, and the analysis presented here indicates that tidally restricted wetlands meet the primary criteria for inventoried ecosystems in that

Effects of crop management, soil type, and climate on N2O emissions from Austrian Soils

Science.gov (United States)

Zechmeister-Boltenstern, Sophie; Sigmund, Elisabeth; Kasper, Martina; Kitzler, Barbara; Haas, Edwin; Wandl, Michael; Strauss, Peter; Poetzelsberger, Elisabeth; Dersch, Georg; Winiwarter, Wilfried; Amon, Barbara

2015-04-01

Within the project FarmClim ("Farming for a better climate") we assessed recent N2O emissions from two selected regions in Austria. Our aim was to deepen the understanding of Austrian N2O fluxes regarding region specific properties. Currently, N2O emissions are estimated with the IPCC default emission factor which only considers the amount of N-input as an influencing factor for N2O emissions. We evaluated the IPCC default emission factor for its validity under spatially distinct environmental conditions. For this two regions for modeling with LandscapeDNDC have been identified in this project. The benefit of using LandscapeDNDC is the detailed illustration of microbial processes in the soil. Required input data to run the model included daily climate data, vegetation properties, soil characteristics and land management. The analysis of present agricultural practices was basis for assessing the hot spots and hot moments of nitrogen emissions on a regional scale. During our work with LandscapeDNDC we were able to adapt specific model algorithms to Austrian agricultural conditions. The model revealed a strong dependency of N2O emissions on soil type. We could estimate how strongly soil texture affects N2O emissions. Based on detailed soil maps with high spatial resolution we calculated region specific contribution to N2O emissions. Accordingly we differentiated regions with deviating gas fluxes compared to the predictions by the IPCC inventory methodology. Taking region specific management practices into account (tillage, irrigation, residuals) calculation of crop rotation (fallow, catch crop, winter wheat, barley, winter barley, sugar beet, corn, potato, onion and rapeseed) resulted in N2O emissions differing by a factor of 30 depending on preceding crop and climate. A maximum of 2% of N fertilizer input was emitted as N2O. Residual N in the soil was a major factor stimulating N2O emissions. Interannual variability was affected by varying N-deposition even in case

Impacts of climate change on power sector NOx emissions: A long-run analysis of the US mid-atlantic region

International Nuclear Information System (INIS)

Chen, Yihsu; Hobbs, Benjamin F.; Hugh Ellis, J.; Crowley, Christian; Joutz, Frederick

2015-01-01

We propose a framework for analyzing the long-run effects of climate change on the spatial and temporal distribution of nitrogen oxide (NOx) emissions from the power sector. Elevated ground-level temperatures could increase electricity demand during the ozone season, altering the generation mixes and ultimately changing emissions. A sequence of load forecasting, supply investment and operation, and facility siting models is used to project spatial and temporal distributions of NOx emissions. Under a worse-case scenario with no renewable additions or other interventions, the results indicate that even if total NOx is limited by cap-and-trade policies, climate-warming-induced changes in the timing of pollution emissions can be significant, especially under warmer or high-load conditions. This suggests that a continued reliance on fossil-fuel together with a temperature sensitivity of generation efficiency and peak electricity demands increases the likelihood that emissions will be greater during the warm days when ozone episodes also occur. The paper advances the integrated assessment by identifying ways at which climate-change-derived energy demand can impact generation mixture, operations and local air pollution. The downscaled emissions can be used in regional air quality models such as the Community Multiscale Air Quality (CMAQ) to project changes in tropospheric ozone due to climate change. -- Highlights: •We develop a framework to study the impact of climate-induced changes on electricity sector. •It could affect spatial and temporal distribution of pollution emissions in the long run. •Under a worse-case assumption, significant emissions during peak demand hours could occur. •It could possibly worsen regional air quality, even if seasonal emissions are constant under cap. •A separate cap or tax can be applied to extreme weather conditions to avoidworsening air quality

Nitrous oxide emissions from manure handling - effects of storage conditions and climate

International Nuclear Information System (INIS)

Sommer, S.G.; Petersen, S.O.

2002-01-01

Stored animal manure and manure applied in the field contributes an estimated 20% to the total anthropogenic emissions of nitrous oxide (N 2 0) in Denmark. Manure composition, handling and climatic conditions may all influence the emission level during storage, but there are relatively few experimental data on emissions of N 2 0 from manure management, including animal houses, slurry stores and manure heaps. Among animal housing systems, very high emission rates have been found with pig deep lifter, and N 2 0 emissions are further stimulated by mechanical mixing. Slurry stores are anaerobic, but a recent study showed that N 2 0 can be produced in porous surface covers such as natural surface crusts, straw or leca pebbles, while no N 2 0 was emitted from uncovered slurry. The emission was significantly related to the water balance, i.e., the difference between evaporation and rain, during dry periods; during wet periods no N 2 0 was emitted. For solid manure, previous studies have typically found that less than 1 % of total N is emitted as N 2 0. Nitrous oxide may be produced throughout the manure heap, provided an environment with both aerobic and anaerobic pockets exists. Profiles from an experimental heap indicated that most of the N 2 0 emitted from solid manure was produced near the surface of the heap. Increasing density appears to stimulate N 2 0 emissions up to a point, where the air exchange is significantly impeded. The IPCC methodology calculates N 2 0 emissions from manure on the basis of total N content (that is, on the basis of volume) and climate region only. Possibly, estimates of N 2 0 emissions from slurry stores could be improved by considering surface area, ammonium content and water balance as input variables. Emissions from solid manure heaps should consider surface area and the potential for composting, as reflected in bulk density and moisture content. (au)

Optical field emission from resonant gold nanorods driven by femtosecond mid-infrared pulses

Energy Technology Data Exchange (ETDEWEB)

Kusa, F. [Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei Tokyo 184-8588 (Japan); Institute of Industrial Science, the University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505 (Japan); Echternkamp, K. E.; Herink, G.; Ropers, C. [4th Physical Institute – Solids and Nanostructures, University of Göttingen, 37077 Göttingen (Germany); Ashihara, S., E-mail: ashihara@iis.u-tokyo.ac.jp [Institute of Industrial Science, the University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505 (Japan)

2015-07-15

We demonstrate strong-field photoelectron emission from gold nanorods driven by femtosecond mid-infrared optical pulses. The maximum photoelectron yield is reached at the localized surface plasmon resonance, indicating that the photoemission is governed by the resonantly-enhanced optical near-field. The wavelength- and field-dependent photoemission yield allows for a noninvasive determination of local field enhancements, and we obtain intensity enhancement factors close to 1300, in good agreement with finite-difference time domain computations.

Impacts of Climate Change Induced Vegetation Responses on BVOC Emissions from Subarctic Heath Ecosystems

DEFF Research Database (Denmark)

Valolahti, Hanna Maritta

The role of biogenic volatile organic compounds (BVOCs) affecting Earths’ climate system is one of the greatest uncertainties when modelling the global climate change. BVOCs presence in the atmosphere can have both positive and negative climate feedback mechanisms when they involve atmospheric...... chemistry and physics. Vegetation is the main source of BVOCs. Their production is directly linked to temperature and the foliar biomass. On global scale, vegetation in subarctic and arctic regions has been modeled to have only minor contribution to annual total BVOC emissions. In these regions cold...... temperature has been regulating annual plant biomass production, but ongoing global warming is more pronounced in these regions than what the global average is. This may increase the importance of subarctic and arctic vegetation as a source of BVOC emissions in near future. This thesis aims to increase...

A modelling approach to estimate carbon emissions from D.R.C. deforestation

Science.gov (United States)

Najdovski, Nicolas; Poulter, Benjamin; Defourny, Pierre; Moreau, Inès; Maignan, Fabienne; Ciais, Philippe; Verhegghen, Astrid; Kibambe Lubamba, Jean-Paul; Jungers, Quentin; De Weirdt, Marjolein; Verbeeck, Hans; MacBean, Natasha; Peylin, Philippe

2014-05-01

With its 1.8 million squared kilometres, the Congo basin dense forest represents the second largest contiguous forest of the world. These extensive forest ecosystems play a significant role in the regulation of global climate by their potential carbon dioxide emissions and carbon storage. Under a stable climate, the vegetation, assumed to be at the equilibrium, is known to present neutral emissions over a year with seasonal variations. However, modifications in temperatures, precipitations, CO2 atmospheric concentrations have the potential to modify this balance leading to higher or lower biomass storage. In addition, deforestation and forest degradation have played a significant role over the past several decades and are expected to become increasingly important in the future. Here, we quantify the relative effects of deforestation and 21st century climate change on carbon emissions in Congo Basin over the next three decades (2005-2035). Carbon dioxide emissions are estimated using a series of moderate resolution (10 km) vegetation maps merged with spatially explicit deforestation projections and developed to work with a prognostic carbon cycle model. The inversion of the deforestation model allowed hindcast land-use patterns back to 1800 by using land cover change rates based on the HYDE database. Simulations were made over the Democratic Republic of Congo (DRC) using the ORCHIDEE dynamic global vegetation model with climate forcing from the CMIP5 Representative Concentration Pathway 8.5 scenario for the HadGEM2. Two simulations were made, a reference simulation with land cover fixed at 2005 and a land cover change simulation with changing climate and CO2, to quantify the net land cover change emissions and climate emissions directly. Because of the relatively high resolution of the model simulations, the spatial patterns of human-driven carbon losses can be tracked in the context of climate change, providing information for mitigation and vulnerability

Simulating Climate Change in Ireland

Science.gov (United States)

Nolan, P.; Lynch, P.

2012-04-01

At the Meteorology & Climate Centre at University College Dublin, we are using the CLM-Community's COSMO-CLM Regional Climate Model (RCM) and the WRF RCM (developed at NCAR) to simulate the climate of Ireland at high spatial resolution. To address the issue of model uncertainty, a Multi-Model Ensemble (MME) approach is used. The ensemble method uses different RCMs, driven by several Global Climate Models (GCMs), to simulate climate change. Through the MME approach, the uncertainty in the RCM projections is quantified, enabling us to estimate the probability density function of predicted changes, and providing a measure of confidence in the predictions. The RCMs were validated by performing a 20-year simulation of the Irish climate (1981-2000), driven by ECMWF ERA-40 global re-analysis data, and comparing the output to observations. Results confirm that the output of the RCMs exhibit reasonable and realistic features as documented in the historical data record. Projections for the future Irish climate were generated by downscaling the Max Planck Institute's ECHAM5 GCM, the UK Met Office HadGEM2-ES GCM and the CGCM3.1 GCM from the Canadian Centre for Climate Modelling. Simulations were run for a reference period 1961-2000 and future period 2021-2060. The future climate was simulated using the A1B, A2, B1, RCP 4.5 & RCP 8.5 greenhouse gas emission scenarios. Results for the downscaled simulations show a substantial overall increase in precipitation and wind speed for the future winter months and a decrease during the summer months. The predicted annual change in temperature is approximately 1.1°C over Ireland. To date, all RCM projections are in general agreement, thus increasing our confidence in the robustness of the results.

Mamizu climate policy: an evaluation of Japanese carbon emissions reduction targets

International Nuclear Information System (INIS)

Pielke, Roger A Jr

2009-01-01

This letter evaluates Japan's so-called 'Mamizu' climate policies proposed in mid-2009 in terms of the implied rates of decarbonization of the Japanese economy for short-term and long-term targets. The letter uses the Kaya identity to structure the evaluation, employing both a bottom up approach (based on projections of future Japanese population, economic growth, and technology) and a top down approach (deriving implied rates of decarbonization consistent with the targets and various rates of economic growth). Both approaches indicate that the Japanese economy would have to achieve rates of decarbonization of 2.6% to meet a 2020 target of reducing emissions by 15% below 2005 levels, and 5.0% to meet a 2050 target of an 80% reduction below 2005 levels. A target of 25% below 1990 emissions proposed by the opposition party (which subsequently formed a government following elections in August 2009) implies a rate of decarbonization of 4.6% annually to 2020. The letter argues that international criticism of Japanese Mamizu climate policy proposals as being too weak was unfounded, and if anything, the proposals may have been too ambitious. In either case, climate policy would be strengthened through the support of a diversity of approaches to decarbonization.

Methane emissions from oceans, coasts, and freshwater habitats: New perspectives and feedbacks on climate

Science.gov (United States)

Hamdan, Leila J.; Wickland, Kimberly P.

2016-01-01

Methane is a powerful greenhouse gas, and atmospheric concentrations have risen 2.5 times since the beginning of the Industrial age. While much of this increase is attributed to anthropogenic sources, natural sources, which contribute between 35% and 50% of global methane emissions, are thought to have a role in the atmospheric methane increase, in part due to human influences. Methane emissions from many natural sources are sensitive to climate, and positive feedbacks from climate change and cultural eutrophication may promote increased emissions to the atmosphere. These natural sources include aquatic environments such as wetlands, freshwater lakes, streams and rivers, and estuarine, coastal, and marine systems. Furthermore, there are significant marine sediment stores of methane in the form of clathrates that are vulnerable to mobilization and release to the atmosphere from climate feedbacks, and subsurface thermogenic gas which in exceptional cases may be released following accidents and disasters (North Sea blowout and Deepwater Horizon Spill respectively). Understanding of natural sources, key processes, and controls on emission is continually evolving as new measurement and modeling capabilities develop, and different sources and processes are revealed. This special issue of Limnology and Oceanography gathers together diverse studies on methane production, consumption, and emissions from freshwater, estuarine, and marine systems, and provides a broad view of the current science on methane dynamics of aquatic ecosystems. Here, we provide a general overview of aquatic methane sources, their contribution to the global methane budget, and key uncertainties. We then briefly summarize the contributions to and highlights of this special issue.

Emissions Scenarios and Fossil-fuel Peaking

Science.gov (United States)

Brecha, R.

2008-12-01

Intergovernmental Panel on Climate Change (IPCC) emissions scenarios are based on detailed energy system models in which demographics, technology and economics are used to generate projections of future world energy consumption, and therefore, of greenhouse gas emissions. Built into the assumptions for these scenarios are estimates for ultimately recoverable resources of various fossil fuels. There is a growing chorus of critics who believe that the true extent of recoverable fossil resources is much smaller than the amounts taken as a baseline for the IPCC scenarios. In a climate optimist camp are those who contend that "peak oil" will lead to a switch to renewable energy sources, while others point out that high prices for oil caused by supply limitations could very well lead to a transition to liquid fuels that actually increase total carbon emissions. We examine a third scenario in which high energy prices, which are correlated with increasing infrastructure, exploration and development costs, conspire to limit the potential for making a switch to coal or natural gas for liquid fuels. In addition, the same increasing costs limit the potential for expansion of tar sand and shale oil recovery. In our qualitative model of the energy system, backed by data from short- and medium-term trends, we have a useful way to gain a sense of potential carbon emission bounds. A bound for 21st century emissions is investigated based on two assumptions: first, that extractable fossil-fuel resources follow the trends assumed by "peak oil" adherents, and second, that little is done in the way of climate mitigation policies. If resources, and perhaps more importantly, extraction rates, of fossil fuels are limited compared to assumptions in the emissions scenarios, a situation can arise in which emissions are supply-driven. However, we show that even in this "peak fossil-fuel" limit, carbon emissions are high enough to surpass 550 ppm or 2°C climate protection guardrails. Some

Natural emissions under future climate condition and their effects on surface ozone in the Yangtze River Delta region, China

Science.gov (United States)

Xie, Min; Shu, Lei; Wang, Ti-jian; Liu, Qian; Gao, Da; Li, Shu; Zhuang, Bing-liang; Han, Yong; Li, Meng-meng; Chen, Pu-long

2017-02-01

The natural emissions of ozone precursors (NOx and VOCs) are sensitive to climate. Future climate change can impact O3 concentrations by perturbing these emissions. To better estimate the variation of natural emissions under different climate conditions and understand its effect on surface O3, we model the present and the future air quality over the Yangtze River Delta (YRD) region by running different simulations with the aid of the WRF-CALGRID model system that contains a natural emission module. Firstly, we estimate the natural emissions at present and in IPCC A1B scenario. The results show that biogenic VOC emission and soil NOx emission over YRD in 2008 is 657 Gg C and 19.1 Gg N, respectively. According to climate change, these emissions in 2050 will increase by 25.5% and 11.5%, respectively. Secondly, the effects of future natural emissions and meteorology on surface O3 are investigated and compared. It is found that the variations in meteorological fields can significantly alter the spatial distribution of O3 over YRD, with the increases of 5-15 ppb in the north and the decreases of -5 to -15 ppb in the south. However, only approximately 20% of the surface O3 increases caused by climate change can be attributed to the natural emissions, with the highest increment up to 2.4 ppb. Finally, Ra (the ratio of impacts from NOx and VOCs on O3 formation) and H2O2/HNO3 (the ratio between the concentrations of H2O2 and HNO3) are applied to study the O3 sensitivity in YRD. The results show that the transition value of H2O2/HNO3 will turn from 0.3 to 0.5 in 2008 to 0.4-0.8 in 2050. O3 formation in the YRD region will be insensitive to VOCs under future climate condition, implying more NOx need to be cut down. Our findings can help us understand O3 variation trend and put forward the reasonable and effective pollution control policies in these famous polluted areas.

Isoprene emissions over Asia 1979-2012: impact of climate and land-use changes

Science.gov (United States)

Stavrakou, T.; Müller, J.-F.; Bauwens, M.; De Smedt, I.; Van Roozendael, M.; Guenther, A.; Wild, M.; Xia, X.

2014-05-01

Due to the scarcity of observational constraints and the rapidly changing environment in East and Southeast Asia, isoprene emissions predicted by models are expected to bear substantial uncertainties. The aim of this study is to improve upon the existing bottom-up estimates, and to investigate the temporal evolution of the fluxes in Asia over 1979-2012. To this purpose, we calculate the hourly emissions at 0.5°×0.5° resolution using the MEGAN-MOHYCAN model driven by ECMWF ERA-Interim climatology. In order to remedy for known biases identified in previous studies, and to improve the simulation of interannual variability and trends in emissions, this study incorporates (i) changes in land use, including the rapid expansion of oil palms, (ii) meteorological variability according to ERA-Interim, (iii) long-term changes in solar radiation (dimming/brightening) constrained by surface network radiation measurements, and (iv) recent experimental evidence that South Asian tropical forests are much weaker isoprene emitters than previously assumed, and on the other hand, that oil palms have a strong isoprene emission capacity. These effects lead to a significant lowering (factor of 2) in the total isoprene fluxes over the studied domain, and to emission reductions reaching a factor of 3.5 in Southeast Asia. The bottom-up annual isoprene emissions for 2005 are estimated at 7.0, 4.8, 8.3, and 2.9 Tg in China, India, Indonesia and Malaysia, respectively. The isoprene flux anomaly over the whole domain and studied period is found to be strongly correlated with the Oceanic Niño Index (r = 0.73), with positive (negative) anomalies related to El Niño (La Niña) years. Changes in temperature and solar radiation are the major drivers of the interannual variability and trends in the emissions, except over semi-arid areas such as northwestern China, Pakistan and Kazakhstan, where soil moisture is by far the main cause of interannual emission changes. In our base simulation, annual

Extending the relationship between global warming and cumulative carbon emissions to multi-millennial timescales

International Nuclear Information System (INIS)

Frölicher, Thomas L; Paynter, David J

2015-01-01

The transient climate response to cumulative carbon emissions (TCRE) is a highly policy-relevant quantity in climate science. The TCRE suggests that peak warming is linearly proportional to cumulative carbon emissions and nearly independent of the emissions scenario. Here, we use simulations of the Earth System Model (ESM) from the Geophysical Fluid Dynamics Laboratory (GFDL) to show that global mean surface temperature may increase by 0.5 °C after carbon emissions are stopped at 2 °C global warming, implying an increase in the coefficient relating global warming to cumulative carbon emissions on multi-centennial timescales. The simulations also suggest a 20% lower quota on cumulative carbon emissions allowed to achieve a policy-driven limit on global warming. ESM estimates from the Coupled Model Intercomparison Project Phase 5 (CMIP5–ESMs) qualitatively agree on this result, whereas Earth System Models of Intermediate Complexity (EMICs) simulations, used in the IPCC 5th assessment report to assess the robustness of TCRE on multi-centennial timescales, suggest a post-emissions decrease in temperature. The reason for this discrepancy lies in the smaller simulated realized warming fraction in CMIP5–ESMs, including GFDL ESM2M, than in EMICs when carbon emissions increase. The temperature response to cumulative carbon emissions can be characterized by three different phases and the linear TCRE framework is only valid during the first phase when carbon emissions increase. For longer timescales, when emissions tape off, two new metrics are introduced that better characterize the time-dependent temperature response to cumulative carbon emissions: the equilibrium climate response to cumulative carbon emissions and the multi-millennial climate response to cumulative carbon emissions. (letter)

Climate-driven ground-level ozone extreme in the fall over the Southeast United States.

Science.gov (United States)

Zhang, Yuzhong; Wang, Yuhang

2016-09-06

Ground-level ozone is adverse to human and vegetation health. High ground-level ozone concentrations usually occur over the United States in the summer, often referred to as the ozone season. However, observed monthly mean ozone concentrations in the southeastern United States were higher in October than July in 2010. The October ozone average in 2010 reached that of July in the past three decades (1980-2010). Our analysis shows that this extreme October ozone in 2010 over the Southeast is due in part to a dry and warm weather condition, which enhances photochemical production, air stagnation, and fire emissions. Observational evidence and modeling analysis also indicate that another significant contributor is enhanced emissions of biogenic isoprene, a major ozone precursor, from water-stressed plants under a dry and warm condition. The latter finding is corroborated by recent laboratory and field studies. This climate-induced biogenic control also explains the puzzling fact that the two extremes of high October ozone both occurred in the 2000s when anthropogenic emissions were lower than the 1980s and 1990s, in contrast to the observed decreasing trend of July ozone in the region. The occurrences of a drying and warming fall, projected by climate models, will likely lead to more active photochemistry, enhanced biogenic isoprene and fire emissions, an extension of the ozone season from summer to fall, and an increase of secondary organic aerosols in the Southeast, posing challenges to regional air quality management.

Performance Investigation of a Solar Heat Driven Adsorption Chiller under Two Different Climatic Conditions

Science.gov (United States)

Choudhury, Biplab; Chatterjee, Pradip Kumar; Habib, Khairul; Saha, Bidyut Baran

2018-06-01

The demand for cooling, especially in the developing economies, is rising at a fast rate. Fast-depleting sources of fossil fuel and environmental concerns necessitate looking for alternative cooling solutions. Solar heat driven adsorption based cooling cycles are environmentally friendly due to their use of natural refrigerants and the thermal compression process. In this paper, a performance simulation study of a basic two-bed solar adsorption chiller has been performed through a transient model for two different climatic locations in India. Effect of operating temperatures and cycle time on the chiller performance has been studied. It is observed that the solar hot water temperature obtained in the composite climate of Delhi (28.65°N, 77.25°E) can run the basic adsorption cooling cycle efficiently throughout the year. Whereas, the monsoon months of July and August in the warm and humid climate of Durgapur (23.48°N, 87.32°E) are unable to supply the required driving heat.

Irreversible climate change due to carbon dioxide emissions

Science.gov (United States)

Solomon, Susan; Plattner, Gian-Kasper; Knutti, Reto; Friedlingstein, Pierre

2009-01-01

The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450–600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the “dust bowl” era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4–1.0 m if 21st century CO2 concentrations exceed 600 ppmv and 0.6–1.9 m for peak CO2 concentrations exceeding ≈1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer. PMID:19179281

Predicting pan-tropical climate change induced forest stock gains and losses-implications for REDD

International Nuclear Information System (INIS)

Gumpenberger, Marlies; Vohland, Katrin; Heyder, Ursula; Poulter, Benjamin; Rammig, Anja; Popp, Alexander; Cramer, Wolfgang; Macey, Kirsten

2010-01-01

Deforestation is a major threat to tropical forests worldwide, contributing up to one-fifth of global carbon emissions into the atmosphere. Despite protection efforts, deforestation of tropical forests has continued in recent years. Providing incentives to reducing deforestation has been proposed in the United Nations Framework Convention on Climate Change (UNFCCC) Bali negotiations in 2007 to decelerate emissions from deforestation (REDD-reduced emissions from deforestation and forest degradation). A number of methodological issues such as ensuring permanence, establishing reference emissions levels that do not reward business-as-usual and having a measuring, reporting and verification system in place are essential elements in implementing successful REDD schemes. To assess the combined impacts of climate and land-use change on tropical forest carbon stocks in the 21st century, we use a dynamic global vegetation model (LPJ DGVM) driven by five different climate change projections under a given greenhouse gas emission scenario (SRES A2) and two contrasting land-use change scenarios. We find that even under a complete stop of deforestation after the period of the Kyoto Protocol (post-2012) some countries may continue to lose carbon stocks due to climate change. Especially at risk is tropical Latin America, although the presence and magnitude of the risk depends on the climate change scenario. By contrast, strong protection of forests could increase carbon uptake in many tropical countries, due to CO 2 fertilization effects, even under altered climate regimes.

CLIMOOR. Climate driven changes in the functioning of heath and moorland ecosystems

Energy Technology Data Exchange (ETDEWEB)

Beier, C. [ed.; Tietema, A.; Riis Nielsen, T.; Emmett, B.; Estiarte, M.; Penuelas, J.; Llorens Guash, L.; Williams, D.; Gordon, C.; Pugh, B.; Roda, F.; Gundersen, P.; Gorissen, A.

2000-01-01

Emission of green house gases, partly generated from human activities, reduces the loss of heat from the earth thereby potentially causing climate change. This change in climate has been predicted to result in a 1-3 deg. C increase in temperature with more vigorous rainstorms and prolonged drought periods in the coming 100 years. The consequence of such climatic changes for the terrestrial ecosystems are largely unknown. In order to improve our understanding of the ecosystem response to climate change and thereby to improve the basis for the international negotiations and political decisions to avoid or minimise climate change and its effects, a European research project CLIMOOR has been initiated. The project is a cross European research project involving 6 research groups from Denmark, the Netherlands, UK and Spain and is funded by EU and the participating institutions. The project investigates the potential effects of warming and drought on heath and moorland ecosystems at four European sites. The ecosystems are manipulated at field scale by reducing the heat loss at night by IR-reflective curtains and by removing the precipitation during a 2 month period in the summer. The effects of these manipulations on the plants and the soil are studied. This report describes the technique used to apply the climate change at field scale and presents some preliminary results after the first growing season. EU and the participating institutions fund CLIMOOR. (au)

Future CO2 Emissions and Climate Change from Existing Energy Infrastructure

Science.gov (United States)

Davis, S. J.; Caldeira, K.; Matthews, D.

2010-12-01

If current greenhouse gas (GHG) concentrations remain constant, the world would be committed to several centuries of increasing global mean temperatures and sea level rise. By contrast, near elimination of anthropogenic CO2 emissions would be required to produce diminishing GHG concentrations consistent with stabilization of mean temperatures. Yet long-lived energy and transportation infrastructure now operating can be expected to contribute substantial CO2 emissions over the next 50 years. Barring widespread retrofitting of existing power plants with carbon capture and storage (CCS) technologies or the early decommissioning of serviceable infrastructure, these “committed emissions” represent infrastructural inertia which may be the primary contributor to total future warming commitment. With respect to GHG emissions, infrastructural inertia may be thought of as having two important and overlapping components: (i) infrastructure that directly releases GHGs to the atmosphere, and (ii) infrastructure that contributes to the continued production of devices that emit GHGs to the atmosphere. For example, the interstate highway and refueling infrastructure in the United States facilitates continued production of gasoline-powered automobiles. Here, we focus only on the warming commitment from infrastructure that directly releases CO2 to the atmosphere. Essentially, we answer the question: What if no additional CO2-emitting devices (e.g., power plants, motor vehicles) were built, but all the existing CO2-emitting devices were allowed to live out their normal lifetimes? What CO2 levels and global mean temperatures would we attain? Of course, the actual lifetime of devices may be strongly influenced by economic and policy constraints. For instance, a ban on new CO2-emitting devices would create tremendous incentive to prolong the lifetime of existing devices. Thus, our scenarios are not realistic, but offer a means of gauging the threat of climate change from existing

Spectral decomposition of regulatory thresholds for climate-driven fluctuations in hydro- and wind power availability

Science.gov (United States)

Wörman, A.; Bottacin-Busolin, A.; Zmijewski, N.; Riml, J.

2017-08-01

Climate-driven fluctuations in the runoff and potential energy of surface water are generally large in comparison to the capacity of hydropower regulation, particularly when hydropower is used to balance the electricity production from covarying renewable energy sources such as wind power. To define the bounds of reservoir storage capacity, we introduce a dedicated reservoir volume that aggregates the storage capacity of several reservoirs to handle runoff from specific watersheds. We show how the storage bounds can be related to a spectrum of the climate-driven modes of variability in water availability and to the covariation between water and wind availability. A regional case study of the entire hydropower system in Sweden indicates that the longest regulation period possible to consider spans from a few days of individual subwatersheds up to several years, with an average limit of a couple of months. Watershed damping of the runoff substantially increases the longest considered regulation period and capacity. The high covariance found between the potential energy of the surface water and wind energy significantly reduces the longest considered regulation period when hydropower is used to balance the fluctuating wind power.

Restoring tides to reduce methane emissions in impounded wetlands: A new and potent Blue Carbon climate change intervention.

Science.gov (United States)

Kroeger, Kevin D; Crooks, Stephen; Moseman-Valtierra, Serena; Tang, Jianwu

2017-09-20

Coastal wetlands are sites of rapid carbon (C) sequestration and contain large soil C stocks. Thus, there is increasing interest in those ecosystems as sites for anthropogenic greenhouse gas emission offset projects (sometimes referred to as "Blue Carbon"), through preservation of existing C stocks or creation of new wetlands to increase future sequestration. Here we show that in the globally-widespread occurrence of diked, impounded, drained and tidally-restricted salt marshes, substantial methane (CH 4 ) and CO 2 emission reductions can be achieved through restoration of disconnected saline tidal flows. Modeled climatic forcing indicates that tidal restoration to reduce emissions has a much greater impact per unit area than wetland creation or conservation to enhance sequestration. Given that GHG emissions in tidally-restricted, degraded wetlands are caused by human activity, they are anthropogenic emissions, and reducing them will have an effect on climate that is equivalent to reduced emission of an equal quantity of fossil fuel GHG. Thus, as a landuse-based climate change intervention, reducing CH 4 emissions is an entirely distinct concept from biological C sequestration projects to enhance C storage in forest or wetland biomass or soil, and will not suffer from the non-permanence risk that stored C will be returned to the atmosphere.

Restoring tides to reduce methane emissions in impounded wetlands: A new and potent Blue Carbon climate change intervention

Science.gov (United States)

Kroeger, Kevin D.; Crooks, Stephen; Moseman-Valtierra, Serena; Tang, Jianwu

2017-01-01

Coastal wetlands are sites of rapid carbon (C) sequestration and contain large soil C stocks. Thus, there is increasing interest in those ecosystems as sites for anthropogenic greenhouse gas emission offset projects (sometimes referred to as “Blue Carbon”), through preservation of existing C stocks or creation of new wetlands to increase future sequestration. Here we show that in the globally-widespread occurrence of diked, impounded, drained and tidally-restricted salt marshes, substantial methane (CH4) and CO2 emission reductions can be achieved through restoration of disconnected saline tidal flows. Modeled climatic forcing indicates that tidal restoration to reduce emissions has a much greater impact per unit area than wetland creation or conservation to enhance sequestration. Given that GHG emissions in tidally-restricted, degraded wetlands are caused by human activity, they are anthropogenic emissions, and reducing them will have an effect on climate that is equivalent to reduced emission of an equal quantity of fossil fuel GHG. Thus, as a landuse-based climate change intervention, reducing CH4 emissions is an entirely distinct concept from biological C sequestration projects to enhance C storage in forest or wetland biomass or soil, and will not suffer from the non-permanence risk that stored C will be returned to the atmosphere.

The implications of intermediate stop operations on aviation emissions and climate

NARCIS (Netherlands)

Linke, F.; Grewe, V.; Gollnick, V

2017-01-01

Among the various transport modes aviation’s impact on climate change deserves special attention. Due to typical flight altitudes in the upper troposphere and above, the effect of aircraft engine emissions like e.g. water vapour, nitrogen oxides and aerosols on

Designing an emissions trading scheme for China. An up-to-date climate policy assessment

Energy Technology Data Exchange (ETDEWEB)

Huebler, Michael [Zentrum fuer Europaeische Wirtschaftsforschung GmbH (ZEW), Mannheim (Germany); Hannover Univ. (Germany). Inst. for Environmental Economics and World Trade; Loeschel, Andreas; Voigt, Sebastian [Zentrum fuer Europaeische Wirtschaftsforschung GmbH (ZEW), Mannheim (Germany)

2014-07-01

We assess recent Chinese climate policy proposals in a multi-region, multi-sector computable general equilibrium model with a Chinese carbon emissions trading scheme (ETS). When the emissions intensity per GDP in 2020 is required to be 45% lower than in 2005, the model simulations indicate that the climate policy-induced welfare loss in 2020, measured as the level of GDP and welfare in 2020 under climate policy relative to their level under business-as-usual (BAU) in the same year, is about 1%. The Chinese welfare loss in 2020 slightly increases in the Chinese rate of economic growth in 2020. When keeping the emissions target fixed at the 2020 level after 2020 in absolute terms, the welfare loss will reach about 2% in 2030. If China's annual economic growth rate is 0.5 percentage points higher (lower), the climate policy-induced welfare loss in 2030 will rise (decline) by about 0.5 percentage points. Full auctioning of carbon allowances results in very similar macroeconomic effects as free allocation, but full auctioning leads to higher reductions in output than free allocation for ETS sectors. Linking the Chinese to the European ETS and restricting the transfer volume to one third of the EU's reduction effort creates at best a small benefit for China, yet with smaller sectoral output reductions than auctioning. These results highlight the importance of designing the Chinese ETS wisely.

Designing an emissions trading scheme for China. An up-to-date climate policy assessment

International Nuclear Information System (INIS)

Huebler, Michael

2014-01-01

We assess recent Chinese climate policy proposals in a multi-region, multi-sector computable general equilibrium model with a Chinese carbon emissions trading scheme (ETS). When the emissions intensity per GDP in 2020 is required to be 45% lower than in 2005, the model simulations indicate that the climate policy-induced welfare loss in 2020, measured as the level of GDP and welfare in 2020 under climate policy relative to their level under business-as-usual (BAU) in the same year, is about 1%. The Chinese welfare loss in 2020 slightly increases in the Chinese rate of economic growth in 2020. When keeping the emissions target fixed at the 2020 level after 2020 in absolute terms, the welfare loss will reach about 2% in 2030. If China's annual economic growth rate is 0.5 percentage points higher (lower), the climate policy-induced welfare loss in 2030 will rise (decline) by about 0.5 percentage points. Full auctioning of carbon allowances results in very similar macroeconomic effects as free allocation, but full auctioning leads to higher reductions in output than free allocation for ETS sectors. Linking the Chinese to the European ETS and restricting the transfer volume to one third of the EU's reduction effort creates at best a small benefit for China, yet with smaller sectoral output reductions than auctioning. These results highlight the importance of designing the Chinese ETS wisely.

Impact of climate change on renewable groundwater resources: assessing the benefits of avoided greenhouse gas emissions using selected CMIP5 climate projections

International Nuclear Information System (INIS)

Portmann, Felix T; Döll, Petra; Eisner, Stephanie; Flörke, Martina

2013-01-01

Reduction of greenhouse gas (GHG) emissions to minimize climate change requires very significant societal effort. To motivate this effort, it is important to clarify the benefits of avoided emissions. To this end, we analysed the impact of four emissions scenarios on future renewable groundwater resources, which range from 1600 GtCO 2 during the 21st century (RCP2.6) to 7300 GtCO 2 (RCP8.5). Climate modelling uncertainty was taken into account by applying the bias-corrected output of a small ensemble of five CMIP5 global climate models (GCM) as provided by the ISI-MIP effort to the global hydrological model WaterGAP. Despite significant climate model uncertainty, the benefits of avoided emissions with respect to renewable groundwater resources (i.e. groundwater recharge (GWR)) are obvious. The percentage of projected global population (SSP2 population scenario) suffering from a significant decrease of GWR of more than 10% by the 2080s as compared to 1971–2000 decreases from 38% (GCM range 27–50%) for RCP8.5 to 24% (11–39%) for RCP2.6. The population fraction that is spared from any significant GWR change would increase from 29% to 47% if emissions were restricted to RCP2.6. Increases of GWR are more likely to occur in areas with below average population density, while GWR decreases of more than 30% affect especially (semi)arid regions, across all GCMs. Considering change of renewable groundwater resources as a function of mean global temperature (GMT) rise, the land area that is affected by GWR decreases of more than 30% and 70% increases linearly with global warming from 0 to 3 ° C. For each degree of GMT rise, an additional 4% of the global land area (except Greenland and Antarctica) is affected by a GWR decrease of more than 30%, and an additional 1% is affected by a decrease of more than 70%. (letter)

Climate Change driven evolution of hazards to Europe's transport infrastructure throughout the twenty-first century

Science.gov (United States)

Matulla, Christoph; Hollósi, Brigitta; Andre, Konrad; Gringinger, Julia; Chimani, Barbara; Namyslo, Joachim; Fuchs, Tobias; Auerbach, Markus; Herrmann, Carina; Sladek, Brigitte; Berghold, Heimo; Gschier, Roland; Eichinger-Vill, Eva

2017-06-01

Road authorities, freight, and logistic industries face a multitude of challenges in a world changing at an ever growing pace. While globalization, changes in technology, demography, and traffic, for instance, have received much attention over the bygone decades, climate change has not been treated with equal care until recently. However, since it has been recognized that climate change jeopardizes many business areas in transport, freight, and logistics, research programs investigating future threats have been initiated. One of these programs is the Conference of European Directors of Roads' (CEDR) Transnational Research Programme (TRP), which emerged about a decade ago from a cooperation between European National Road Authorities and the EU. This paper presents findings of a CEDR project called CliPDaR, which has been designed to answer questions from road authorities concerning climate-driven future threats to transport infrastructure. Pertaining results are based on two potential future socio-economic pathways of mankind (one strongly economically oriented "A2" and one more balanced scenario "A1B"), which are used to drive global climate models (GCMs) producing global and continental scale climate change projections. In order to achieve climate change projections, which are valid on regional scales, GCM projections are downscaled by regional climate models. Results shown here originate from research questions raised by European Road Authorities. They refer to future occurrence frequencies of severely cold winter seasons in Fennoscandia, to particularly hot summer seasons in the Iberian Peninsula and to changes in extreme weather phenomena triggering landslides and rutting in Central Europe. Future occurrence frequencies of extreme winter and summer conditions are investigated by empirical orthogonal function analyses of GCM projections driven with by A2 and A1B pathways. The analysis of future weather phenomena triggering landslides and rutting events requires

Climate Change and Agriculture: Can market governance mechanisms reduce emissions from the food system fairly and effectively?

Energy Technology Data Exchange (ETDEWEB)

Garnett, Tara

2012-05-15

Climate and agriculture are inextricably linked: the climate affects agricultural production and is itself affected by agricultural emissions. Agriculture is responsible for 30 per cent of global greenhouse gas emissions. How agriculture is practised therefore has significant potential for mitigating climate change, for providing food security and for improving the livelihoods of millions of food producers worldwide. There is growing interest in the use of market governance mechanisms for tackling climate change by giving the financial incentives to make the kinds of changes that are required. But how widely are these mechanisms being used in agriculture, and are they effective in reducing emissions? What impact do they have on adaptation and other aspects of sustainable development? Are they able to balance the competing demands of producers and consumers, the environment and food security? The key messages emerging from this study are that economic measures have a vital part to play within this regulatory context, but they need to be designed with care. To be effective, emissions from food production and consumption must be addressed together. If not, emissions reduced in one region will simply be displaced elsewhere. A balance needs to be struck by applying a mix of approaches – regulatory, economic, voluntary, and information: no single measure will be effective in achieving emissions reductions on its own. 'Soft' measures, such as voluntary agreements and information have a part to play in providing an enabling context for action, but they must be backed up by 'harder' regulatory or economic measures. Regulation, in the form of a cap on emissions, is a prerequisite for other market governance measures to function well. To be effective, MGMs need to consider the social, cultural and economic context within which they operate.

Great expectations. Can international emissions trading deliver an equitable climate regime?

International Nuclear Information System (INIS)

Baumert, Kevin A.; Perkaus, James F.; Kete, Nancy

2003-01-01

Climate change equity debates tend to focus on achieving a fair and global 'allocation' of emission rights among countries. Allocation proposals typically envision, if implicitly, two purposes for international emissions trading. First, trading is expected to serve as a cost-effective means of promoting compliance with emissions targets. Second, trading is posited as a means to generate financial transfers, typically from industrialized to transitioning and developing countries. This article investigates the common assumption that international emissions trading will effectively serve both of these purposes. We conclude that the two purposes might not be mutually supportive, and that efforts to use international emissions trading as a financial transfer mechanism may potentially undermine cost-effectiveness goals. International emissions trading on a global scale would create new risks in terms of both cost-effectiveness and environmental performance, some of which will be challenging to manage. In particular, uncertainties over market prices and trading eligibility, coupled with the costs of participation, may together be the Achilles heel of some allocation proposals that entail large financial transfers from industrialized to developing countries. Any proposal for an 'equitable' allocation of emission allowances, we conclude, must be cognizant of the risks and costs implied by a reliance on international emissions trading. We offer some suggestions to this end

CO{sub 2} emissions from battery-driven electromobiles; CO{sub 2}-Emissionen von Batterie-Elektrofahrzeugen

Energy Technology Data Exchange (ETDEWEB)

Erdmann, Georg [Technische Univ. Berlin (Germany). Fachgebiet Energiesysteme

2009-10-15

For all the euphoria currently surrounding electromobility, electrically powered road vehicles too have their drawbacks. While the vehicles themselves emit no climatically harmful greenhouses gases during operation, the production of the electricity that drives them is associated with a greater or lesser amount of CO{sub 2} emissions, depending on the production chain. Is it conceivable that private electromobiles offer no advantage after all in terms of climate protection? Be it as it may, this question must be answered before electromobiles become a means of mass transport.

Climate and Health Impacts of US Emissions Reductions Consistent with 2 C

Science.gov (United States)

Shindell, Drew T.; Lee, Yunha; Faluvegi, Greg

2016-01-01

An emissions trajectory for the US consistent with 2 C warming would require marked societal changes, making it crucial to understand the associated benefits. Previous studies have examined technological potentials and implementation costs and public health benefits have been quantified for less-aggressive potential emissions-reduction policies, but researchers have not yet fully explored the multiple benefits of reductions consistent with 2 C. We examine the impacts of such highly ambitious scenarios for clean energy and vehicles. US transportation emissions reductions avoid approx.0.03 C global warming in 2030 (0.15 C in 2100), whereas energy emissions reductions avoid approx.0.05-0.07 C 2030 warming (approx.0.25 C in 2100). Nationally, however, clean energy policies produce climate disbenefits including warmer summers (although these would be eliminated by the remote effects of similar policies if they were undertaken elsewhere). The policies also greatly reduce damaging ambient particulate matter and ozone. By 2030, clean energy policies could prevent approx.175,000 premature deaths, with approx.22,000 (11,000-96,000; 95% confidence) fewer annually thereafter, whereas clean transportation could prevent approx.120,000 premature deaths and approx.14,000 (9,000-52,000) annually thereafter. Near-term national benefits are valued at approx.US$250 billion (140 billion to 1,050billion) per year, which is likely to exceed implementation costs. Including longer-term, worldwide climate impacts, benefits roughly quintuple, becoming approx.5-10 times larger than estimated implementation costs. Achieving the benefits, however, would require both larger and broader emissions reductions than those in current legislation or regulations.

Reducing greenhouse gas emissions for climate stabilization: framing regional options.

Science.gov (United States)

Olabisi, Laura Schmitt; Reich, Peter B; Johnson, Kris A; Kapuscinski, Anne R; Su, Sangwon H; Wilson, Elizabeth J

2009-03-15

The Intergovernmental Panel on Climate Change (IPCC) has stated that stabilizing atmospheric CO2 concentrations will require reduction of global greenhouse gas (GHG) emissions by as much as 80% by 2050. Subnational efforts to cut emissions will inform policy development nationally and globally. We projected GHG mitigation strategies for Minnesota, which has adopted a strategic goal of 80% emissions reduction by 2050. A portfolio of conservation strategies, including electricity conservation, increased vehicle fleet fuel efficiency, and reduced vehicle miles traveled, is likely the most cost-effective option for Minnesota and could reduce emissions by 18% below 2005 levels. An 80% GHG reduction would require complete decarbonization of the electricity and transportation sectors, combined with carbon capture and sequestration at power plants, or deep cuts in other relatively more intransigent GHG-emitting sectors. In order to achieve ambitious GHG reduction goals, policymakers should promote aggressive conservation efforts, which would probably have negative net costs, while phasing in alternative fuels to replace coal and motor gasoline over the long-term.

Reducing greenhouse gas emissions for climate stabilization: framing regional options

Energy Technology Data Exchange (ETDEWEB)

Laura Schmitt Olabisi; Peter B. Reich; Kris A. Johnson; Anne R. Kapuscinski; Sangwon Suh; Elizabeth J. Wilson [University of Minnesota, Saint Paul, MN (United States). Ecosystem Science and Sustainability Initiative

2009-03-15

The Intergovernmental Panel on Climate Change (IPCC) has stated that stabilizing atmospheric CO{sub 2} concentrations will require reduction of global greenhouse gas (GHG) emissions by as much as 80% by 2050. Subnational efforts to cut emissions will inform policy development nationally and globally. We projected GHG mitigation strategies for Minnesota, which has adopted a strategic goal of 80% emissions reduction by 2050. A portfolio of conservation strategies, including electricity conservation, increased vehicle fleet fuel efficiency, and reduced vehicle miles traveled, is likely the most cost-effective option for Minnesota and could reduce emissions by 18% below 2005 levels. An 80% GHG reduction would require complete decarbonization of the electricity and transportation sectors, combined with carbon capture and sequestration at power plants, or deep cuts in other relatively more intransigent GHG-emitting sectors. In order to achieve ambitious GHG reduction goals, policymakers should promote aggressive conservation efforts, which would probably have negative net costs, while phasing in alternative fuels to replace coal and motor gasoline over the long-term. 31 refs., 3 figs., 1 tab.

Field Performance of Inverter-Driven Heat Pumps in Cold Climates

Energy Technology Data Exchange (ETDEWEB)

Williamson, James [Consortium of Advanced Residential Buildings, Norwalk, CT (United States); Aldrich, Robb [Consortium of Advanced Residential Buildings, Norwalk, CT (United States)

2015-08-19

Traditionally, air-source heat pumps (ASHPs) have been used more often in warmer climates; however, some new ASHPs are gaining ground in colder areas. These systems operate at subzero (Fahrenheit) temperatures and many do not include backup electric resistance elements. There are still uncertainties, however, about capacity and efficiency in cold weather. Also, questions such as “how cold is too cold?” do not have clear answers. These uncertainties could lead to skepticism among homeowners; poor energy savings estimates; suboptimal system selection by heating, ventilating, and air-conditioning contractors; and inconsistent energy modeling. In an effort to better understand and characterize the heating performance of these units in cold climates, the U.S. Department of Energy Building America team, Consortium for Advanced Residential Buildings (CARB), monitored seven inverter-driven, ductless ASHPs across the Northeast. Operating data were collected for three Mitsubishi FE18 units, three Mitsubishi FE12 units, and one Fujitsu 15RLS2 unit. The intent of this research was to assess heat output, electricity consumption, and coefficients of performance (COPs) at various temperatures and load conditions. This assessment was accomplished with long- and short-term tests that measured power consumption; supply, return, and outdoor air temperatures; and airflow through the indoor fan coil.

Control of spontaneous emission from a microwave-field-driven four-level atom in an anisotropic photonic crystal

Science.gov (United States)

Zhang, Duo; Li, Jiahua; Ding, Chunling; Yang, Xiaoxue

2012-05-01

The spontaneous emission properties of a microwave-field-driven four-level atom embedded in anisotropic double-band photonic crystals (PCs) are investigated. We discuss the influences of the band-edge positions, Rabi frequency and detuning of the microwave field on the emission spectrum. It is found that several interesting features such as spectral-line enhancement, spectral-line suppression, spectral-line overlap, and multi-peak structures can be observed in the spectra. The proposed scheme can be achieved by use of a microwave-coupled field into hyperfine levels in rubidium atom confined in a photonic crystal. These theoretical investigations may provide more degrees of freedom to manipulate the atomic spontaneous emission.

Spatially explicit integrated modeling and economic valuation of climate driven land use change and its indirect effects.

Science.gov (United States)

Bateman, Ian; Agarwala, Matthew; Binner, Amy; Coombes, Emma; Day, Brett; Ferrini, Silvia; Fezzi, Carlo; Hutchins, Michael; Lovett, Andrew; Posen, Paulette

2016-10-01

We present an integrated model of the direct consequences of climate change on land use, and the indirect effects of induced land use change upon the natural environment. The model predicts climate-driven shifts in the profitability of alternative uses of agricultural land. Both the direct impact of climate change and the induced shift in land use patterns will cause secondary effects on the water environment, for which agriculture is the major source of diffuse pollution. We model the impact of changes in such pollution on riverine ecosystems showing that these will be spatially heterogeneous. Moreover, we consider further knock-on effects upon the recreational benefits derived from water environments, which we assess using revealed preference methods. This analysis permits a multi-layered examination of the economic consequences of climate change, assessing the sequence of impacts from climate change through farm gross margins, land use, water quality and recreation, both at the individual and catchment scale. Copyright © 2016 Elsevier Ltd. All rights reserved.

The influence of coral reefs and climate change on wave-driven flooding of tropical coastlines

Science.gov (United States)

Quataert, Ellen; Storlazzi, Curt; van Rooijen, Arnold; van Dongeren, Ap; Cheriton, Olivia

2015-01-01

A numerical model, XBeach, calibrated and validated on field data collected at Roi-Namur Island on Kwajalein Atoll in the Republic of Marshall Islands, was used to examine the effects of different coral reef characteristics on potential coastal hazards caused by wave-driven flooding and how these effects may be altered by projected climate change. The results presented herein suggest that coasts fronted by relatively narrow reefs with steep fore reef slopes (~1:10 and steeper) and deeper, smoother reef flats are expected to experience the highest wave runup. Wave runup increases for higher water levels (sea level rise), higher waves, and lower bed roughness (coral degradation), which are all expected effects of climate change. Rising sea levels and climate change will therefore have a significant negative impact on the ability of coral reefs to mitigate the effects of coastal hazards in the future.

The influence of coral reefs and climate change on wave-driven flooding of tropical coastlines

Science.gov (United States)

Quataert, Ellen; Storlazzi, Curt; Rooijen, Arnold; Cheriton, Olivia; Dongeren, Ap

2015-08-01

A numerical model, XBeach, calibrated and validated on field data collected at Roi-Namur Island on Kwajalein Atoll in the Republic of Marshall Islands, was used to examine the effects of different coral reef characteristics on potential coastal hazards caused by wave-driven flooding and how these effects may be altered by projected climate change. The results presented herein suggest that coasts fronted by relatively narrow reefs with steep fore reef slopes (~1:10 and steeper) and deeper, smoother reef flats are expected to experience the highest wave runup. Wave runup increases for higher water levels (sea level rise), higher waves, and lower bed roughness (coral degradation), which are all expected effects of climate change. Rising sea levels and climate change will therefore have a significant negative impact on the ability of coral reefs to mitigate the effects of coastal hazards in the future.

Germany's climate policy: Facing an automobile dilemma

International Nuclear Information System (INIS)

Gössling, Stefan; Metzler, Daniel

2017-01-01

Germany has one of the most ambitious climate policy goals worldwide, having pledged to reduce national emissions by 40% by 2020, and 80–95% by 2050 (base year: 1990). 2015 data suggests that progress on decarbonisation has slowed, also because emissions from the transport sector have grown. Road transport, which is contributing 20.5% to Germany's CO_2 emissions, has become a major obstacle to achieving the country's policy goals. This paper analyses energy use from road transport in order to provide a better understanding of emissions from this sub-sector. Data is derived from representative longitudinal household surveys as well as mobility and fuel diaries for the period 2002–2015. Analysis reveals significant growth in energy-inefficient car choices, as well as considerable differences in mobility patterns (distances driven, driving styles) and actual fuel consumption between car segments. Findings suggest that German transport policies will fail to deliver significant emission reductions if complexities in car model choices and use patterns are ignored. Both command-and-control and market-based measures will be needed to align the transport sector with climate goals, while persisting policy inconsistencies will also have to be addressed. Findings are of central relevance for EU-wide and global climate policy in the transport sector. - Highlights: • Emissions from German road transport have remained constant between 1990 and 2015. • Non-progress on transport decarbonisation is barrier to national mitigation goals. • Analysis shows that wide range of complexities are overlooked by government. • Policies need to consider car fleet segmentation and driving patterns. • Command-and-control as well as market-based measures needed.

Theropod Fauna from Southern Australia Indicates High Polar Diversity and Climate-Driven Dinosaur Provinciality

Science.gov (United States)

Benson, Roger B. J.; Rich, Thomas H.; Vickers-Rich, Patricia; Hall, Mike

2012-01-01

hallmark ‘Gondwanan’ fauna of South America and Africa may therefore reflect climate-driven provinciality, not vicariant evolution driven by continental fragmentation. However, vicariance may still be detected at lower phylogenetic levels. PMID:22615916

Impact of wind-driven rain on historic brick wall buildings in a moderately cold and humid climate: Numerical analyses of mould growth risk, indoor climate and energy consumption

DEFF Research Database (Denmark)

Masaru, Abuku; Janssen, Hans; Roels, Staf

2009-01-01

This paper gives an onset to whole building hygrothermal modelling in which the interaction between interior and exterior climates via building enclosures is simulated under a moderately cold and humid climate. The focus is particularly on the impact of wind-driven rain (WDR) oil the hygrothermal...... response, mould growth at interior wall surfaces, indoor climate and energy consumption. First the WDR load oil the facades of a 4 m x 4 m x 10 m tower is determined. Then the hygrothermal behaviour of the brick walls is analysed oil a horizontal slice through the tower. The simulations demonstrate...

Alignment of policies to maximize the climate benefits of diesel vehicles through control of particulate matter and black carbon emissions

International Nuclear Information System (INIS)

Minjares, Ray; Blumberg, Kate; Posada Sanchez, Francisco

2013-01-01

Diesel vehicles offer greater fuel-efficiency and lower greenhouse gas emissions at a time when national governments seek to reduce the energy and climate impacts of the vehicle fleet. Policies that promote diesels like preferential fuel taxes, fuel economy standards and greenhouse gas emission standards can produce higher emissions of diesel particulate matter if diesel particulate filters or equivalent emission control technology is not in place. This can undermine the expected climate benefits of dieselization and increase impacts on public health. This paper takes a historical look at Europe to illustrate the degree to which dieselization and lax controls on particulate matter can undermine the potential benefits sought from diesel vehicles. We show that countries on the dieselization pathway can fully capture the value of diesels with the adoption of tailpipe emission standards equivalent to Euro 6 or Tier 2 for passenger cars, and fuel quality standards that limit the sulfur content of diesel fuel to no greater than 15 ppm. Adoption of these policies before or in parallel with adoption of fuel consumption and greenhouse gas standards can avert the negative impacts of dieselization. - Highlights: ► Preferential tax policies have increased the dieselization of some light-duty vehicle fleets. ► Dieselization paired with lax emission standards produces large black carbon emissions. ► Diesel black carbon undermines the perceived climate benefits of diesel vehicles. ► Stringent controls on diesel particulate emissions will also reduce black carbon. ► Euro 6/VI equivalent emission standards can preserve the climate benefits of diesel vehicles

Modeling biomass burning and related carbon emissions during the 21st century in Europe

KAUST Repository

Migliavacca, Mirco; Dosio, Alessandro; Camia, Andrea; Hobourg, Rasmus; Houston-Durrant, Tracy; Kaiser, Johannes W.; Khabarov, Nikolay; Krasovskii, Andrey A.; Marcolla, Barbara; San Miguel-Ayanz, Jesus; Ward, Daniel S.; Cescatti, Alessandro

2013-01-01

In this study we present an assessment of the impact of future climate change on total fire probability, burned area, and carbon (C) emissions from fires in Europe. The analysis was performed with the Community Land Model (CLM) extended with a prognostic treatment of fires that was specifically refined and optimized for application over Europe. Simulations over the 21st century are forced by five different high-resolution Regional Climate Models under the Special Report on Emissions Scenarios A1B. Both original and bias-corrected meteorological forcings is used. Results show that the simulated C emissions over the present period are improved by using bias corrected meteorological forcing, with a reduction of the intermodel variability. In the course of the 21st century, burned area and C emissions from fires are shown to increase in Europe, in particular in the Mediterranean basins, in the Balkan regions and in Eastern Europe. However, the projected increase is lower than in other studies that did not fully account for the effect of climate on ecosystem functioning. We demonstrate that the lower sensitivity of burned area and C emissions to climate change is related to the predicted reduction of the net primary productivity, which is identified as the most important determinant of fire activity in the Mediterranean region after anthropogenic interaction. This behavior, consistent with the intermediate fire-productivity hypothesis, limits the sensitivity of future burned area and C emissions from fires on climate change, providing more conservative estimates of future fire patterns, and demonstrates the importance of coupling fire simulation with a climate driven ecosystem productivity model.

Modeling biomass burning and related carbon emissions during the 21st century in Europe

KAUST Repository

Migliavacca, Mirco

2013-12-01

In this study we present an assessment of the impact of future climate change on total fire probability, burned area, and carbon (C) emissions from fires in Europe. The analysis was performed with the Community Land Model (CLM) extended with a prognostic treatment of fires that was specifically refined and optimized for application over Europe. Simulations over the 21st century are forced by five different high-resolution Regional Climate Models under the Special Report on Emissions Scenarios A1B. Both original and bias-corrected meteorological forcings is used. Results show that the simulated C emissions over the present period are improved by using bias corrected meteorological forcing, with a reduction of the intermodel variability. In the course of the 21st century, burned area and C emissions from fires are shown to increase in Europe, in particular in the Mediterranean basins, in the Balkan regions and in Eastern Europe. However, the projected increase is lower than in other studies that did not fully account for the effect of climate on ecosystem functioning. We demonstrate that the lower sensitivity of burned area and C emissions to climate change is related to the predicted reduction of the net primary productivity, which is identified as the most important determinant of fire activity in the Mediterranean region after anthropogenic interaction. This behavior, consistent with the intermediate fire-productivity hypothesis, limits the sensitivity of future burned area and C emissions from fires on climate change, providing more conservative estimates of future fire patterns, and demonstrates the importance of coupling fire simulation with a climate driven ecosystem productivity model.

Carbon taxes and tradeable emissions permits: the economic impacts of climate change policies in New Zealand

Energy Technology Data Exchange (ETDEWEB)

Chisholm, A.; Porter, M. [Tasman Institute (Australia)

1994-12-31

Examines the potential economic impacts on New Zealand of climate change policy covering carbon taxes, expanding forest areas as carbon sinks (including selling plantation based emission credits to other OECD nations), and emissions quotas. It is concluded that climate change policy appears to offer high short-term economic costs and little prospect of longer-term economic gain, apart from uncertain environmental benefits. If the Government pursues an active policy to stabilise gross emissions of carbon dioxide at 1990 levels, short term losses in national output and real spending power could be around 0.5 to 1% of GDP. Any major intervention by the New Zealand Government to alter energy use patterns would bring about structural changes in the economy. 4 tabs., 12 refs.

The contribution of China's emissions to global climate forcing.

Science.gov (United States)

Li, Bengang; Gasser, Thomas; Ciais, Philippe; Piao, Shilong; Tao, Shu; Balkanski, Yves; Hauglustaine, Didier; Boisier, Juan-Pablo; Chen, Zhuo; Huang, Mengtian; Li, Laurent Zhaoxin; Li, Yue; Liu, Hongyan; Liu, Junfeng; Peng, Shushi; Shen, Zehao; Sun, Zhenzhong; Wang, Rong; Wang, Tao; Yin, Guodong; Yin, Yi; Zeng, Hui; Zeng, Zhenzhong; Zhou, Feng

2016-03-17

Knowledge of the contribution that individual countries have made to global radiative forcing is important to the implementation of the agreement on "common but differentiated responsibilities" reached by the United Nations Framework Convention on Climate Change. Over the past three decades, China has experienced rapid economic development, accompanied by increased emission of greenhouse gases, ozone precursors and aerosols, but the magnitude of the associated radiative forcing has remained unclear. Here we use a global coupled biogeochemistry-climate model and a chemistry and transport model to quantify China's present-day contribution to global radiative forcing due to well-mixed greenhouse gases, short-lived atmospheric climate forcers and land-use-induced regional surface albedo changes. We find that China contributes 10% ± 4% of the current global radiative forcing. China's relative contribution to the positive (warming) component of global radiative forcing, mainly induced by well-mixed greenhouse gases and black carbon aerosols, is 12% ± 2%. Its relative contribution to the negative (cooling) component is 15% ± 6%, dominated by the effect of sulfate and nitrate aerosols. China's strongest contributions are 0.16 ± 0.02 watts per square metre for CO2 from fossil fuel burning, 0.13 ± 0.05 watts per square metre for CH4, -0.11 ± 0.05 watts per square metre for sulfate aerosols, and 0.09 ± 0.06 watts per square metre for black carbon aerosols. China's eventual goal of improving air quality will result in changes in radiative forcing in the coming years: a reduction of sulfur dioxide emissions would drive a faster future warming, unless offset by larger reductions of radiative forcing from well-mixed greenhouse gases and black carbon.

Climate and air quality-driven scenarios of ozone and aerosol precursor abatement

International Nuclear Information System (INIS)

Rypdal, Kristin; Rive, Nathan; Berntsen, Terje; Fagerli, Hilde; Klimont, Zbigniew; Mideksa, Torben K.; Fuglestvedt, Jan S.

2009-01-01

In addition to causing domestic and regional environmental effects, many air pollutants contribute to radiative forcing (RF) of the climate system. However, climate effects are not considered when cost-effective abatement targets for these pollutants are established, nor are they included in current international climate agreements. We construct air pollution abatement scenarios in 2030 which target cost-effective reductions in RF in the EU, USA, and China and compare these to abatement scenarios which instead target regional ozone effects and particulate matter concentrations. Our analysis covers emissions of PM (fine, black carbon and organic carbon), SO 2 , NO x , CH 4 , VOCs, and CO. We find that the effect synergies are strong for PM/BC, VOC, CO and CH 4 . While an air quality strategy targeted at reducing ozone will also reduce RF, this will not be the case for a strategy targeting particulate matter. Abatement in China dominates RF reduction, but there are cheap abatement options also available in the EU and USA. The justification for international cooperation on air quality issues is underlined when the co-benefits of reduced RF are considered. Some species, most importantly SO 2 , contribute a negative forcing on climate. We suggest that given current knowledge, NO x and SO 2 should be ignored in RF-targeted abatement policies.

Carbon emissions from U.S. ethylene production under climate change policies.

Science.gov (United States)

Ruth, Matthias; Amato, Anthony D; Davidsdottir, Brynhildur

2002-01-15

This paper presents the results from a dynamic computer model of U.S. ethylene production, designed to explore implications of alternative climate change policies for the industry's energy use and carbon emissions profiles. The model applies to the aggregate ethylene industry but distinguishes its main cracker types, fuels used as feedstocks and for process energy, as well as the industry's capital vintage structure and vintage-specific efficiencies. Results indicate that policies which increase the cost of carbon of process energy-such as carbon taxes or carbon permit systems-are relatively blunt instruments for cutting carbon emissions from ethylene production. In contrast, policies directly affecting the relative efficiencies of new to old capital-such as R&D stimuli or accelerated depreciation schedules-may be more effective in leveraging the industry's potential for carbon emissions reductions.

Quantitative criterion for quantum interference within spontaneous emission modification of a driven ladder atom

International Nuclear Information System (INIS)

Liu Jiaren; Zhang Zhiyi; Xiao George; Grover, C P

2003-01-01

The spontaneous emission spectrum of a ladder three-level atom with an upper transition driven by a coherent field is calculated under a universal model where various decays, any incoherent pumping and coherent driving are taken into account. The analytical expression for the spectrum profile is given on the basis of the quantum regression theorem. To our knowledge, it is the first time that the quantitative criterion condition Ω ab - γ ac vertical bar, under which quantum destructive interference induced by the coherent driving field occurs, is deduced for the modification of spontaneous emission from the middle level to the ground level. The roles and limits of incoherent pumping, coherent driving and experimental configuration are discussed for realizing the quantum interference and reducing the Doppler effects

Greenhouse gas emission and exergy analyses of an integrated trigeneration system driven by a solid oxide fuel cell

International Nuclear Information System (INIS)

Chitsaz, Ata; Mahmoudi, S. Mohammad S.; Rosen, Marc A.

2015-01-01

Exergy and greenhouse gas emission analyses are performed for a novel trigeneration system driven by a solid oxide fuel cell (SOFC). The trigeneration system also consists of a generator-absorber heat exchanger (GAX) absorption refrigeration system and a heat exchanger to produce electrical energy, cooling and heating, respectively. Four operating cases are considered: electrical power generation, electrical power and cooling cogeneration, electrical power and heating cogeneration, and trigeneration. Attention is paid to numerous system and environmental performance parameters, namely, exergy efficiency, exergy destruction rate, and greenhouse gas emissions. A maximum enhancement of 46% is achieved in the exergy efficiency when the SOFC is used as the primary mover for the trigeneration system compared to the case when the SOFC is used as a standalone unit. The main sources of irreversibility are observed to be the air heat exchanger, the SOFC and the afterburner. The unit CO 2 emission (in kg/MWh) is considerably higher for the case in which only electrical power is generated. This parameter is reduced by half when the system is operates in a trigeneration mode. - Highlights: • A novel trigeneration system driven by a solid oxide fuel cell is analyzed. • Exergy and greenhouse gas emission analyses are performed. • Four special cases are considered. • An enhancement of up to 46% is achieved in exergy efficiency. • The CO 2 emission drops to a relatively low value for the tri-generation case

Changes in future air quality, deposition, and aerosol-cloud interactions under future climate and emission scenarios

Energy Technology Data Exchange (ETDEWEB)

Glotfelty, Timothy; Zhang, Yang; Karamchandani, Prakash; Streets, David G.

2016-08-01

The prospect of global climate change will have wide scale impacts, such as ecological stress and human health hazards. One aspect of concern is future changes in air quality that will result from changes in both meteorological forcing and air pollutant emissions. In this study, the GU-WRF/Chem model is employed to simulate the impact of changing climate and emissions following the IPCC AR4 SRES A1B scenario. An average of 4 future years (2020, 2030, 2040, and 2050) is compared against an average of 2 current years (2001 and 2010). Under this scenario, by the Mid-21st century global air quality is projected to degrade with a global average increase of 2.5 ppb in the maximum 8-hr O₃ level and of 0.3 mg m³ in 24-hr average PM2.5. However, PM2.5 changes are more regional due to regional variations in primary aerosol emissions and emissions of gaseous precursor for secondary PM2.5. Increasing NOx emissions in this scenario combines with a wetter climate elevating levels of OH, HO₂, H₂O₂, and the nitrate radical and increasing the atmosphere’s near surface oxidation state. This differs from findings under the RCP scenarios that experience declines in OH from reduced NOx emissions, stratospheric recovery of O₃, and increases in CH₄ and VOCs. Increasing NO_x and O₃ levels enhances the nitrogen and O₃ deposition, indicating potentially enhanced crop damage and ecosystem stress under this scenario. The enhanced global aerosol level results in enhancements in aerosol optical depth, cloud droplet number concentration, and cloud optical thickness. This leads to dimming at the Earth’s surface with a global average reduction in shortwave radiation of 1.2 W m² . This enhanced dimming leads to a more moderate warming trend and different trends in radiation than those found in NCAR’s CCSM simulation, which does not include the advanced chemistry and aerosol

Misperceived climate friendliness of organic food and consumer willingness to pay for actual greenhouse gas emission reduction

DEFF Research Database (Denmark)

Olsen, Søren Bøye; Christensen, Tove; Denver, Sigrid

2015-01-01

Organic farming practices are generally associated with lower environmental impacts than conventional farming but this does not generally hold true in a climate context. A recent meta-analysis shows that organic milk production often has higher greenhouse gas (GHG) emissions per kilo milk produce...... in consumers’ preferences. Hence, if reduced GHG emissions are to be pursued by increased consumption of climate friendlier food then marketing efforts and information strategies need to be targeted specifically to different segments of the population....

Impacts of future climate change and effects of biogenic emissions on surface ozone and particulate matter concentrations in the United States

Directory of Open Access Journals (Sweden)

Y. F. Lam

2011-05-01

Full Text Available Simulations of present and future average regional ozone and PM_2.5 concentrations over the United States were performed to investigate the potential impacts of global climate change and emissions on regional air quality using CMAQ. Various emissions and climate conditions with different biogenic emissions and domain resolutions were implemented to study the sensitivity of future air quality trends from the impacts of changing biogenic emissions. A comparison of GEOS-Chem and CMAQ was performed to investigate the effect of downscaling on the prediction of future air quality trends. For ozone, the impacts of global climate change are relatively smaller when compared to the impacts of anticipated future emissions reduction, except for the Northeast area, where increasing biogenic emissions due to climate change have stronger positive effects (increases to the regional ozone air quality. The combination effect from both climate change and emission reductions leads to approximately a 10 % or 5 ppbv decrease of the maximum daily average eight-hour ozone (MDA8 over the Eastern United States. For PM_2.5, the impacts of global climate change have shown insignificant effect, where as the impacts of anticipated future emissions reduction account for the majority of overall PM_2.5 reductions. The annual average 24-h PM_2.5 of the future-year condition was found to be about 40 % lower than the one from the present-year condition, of which 60 % of its overall reductions are contributed to by the decrease of SO₄ and NO₃ particulate matters. Changing the biogenic emissions model increases the MDA8 ozone by about 5–10 % or 3–5 ppbv in the Northeast area. Conversely, it reduces the annual average PM_2.5 by 5 % or 1.0 μg m⁻³ in the Southeast region.

Climate-change-driven deterioration of water quality in a mineralized watershed.

Science.gov (United States)

Todd, Andrew S; Manning, Andrew H; Verplanck, Philip L; Crouch, Caitlin; McKnight, Diane M; Dunham, Ryan

2012-09-04

A unique 30-year streamwater chemistry data set from a mineralized alpine watershed with naturally acidic, metal-rich water displays dissolved concentrations of Zn and other metals of ecological concern increasing by 100-400% (400-2000 μg/L) during low-flow months, when metal concentrations are highest. SO(4) and other major ions show similar increases. A lack of natural or anthropogenic land disturbances in the watershed during the study period suggests that climate change is the underlying cause. Local mean annual and mean summer air temperatures have increased at a rate of 0.2-1.2 °C/decade since the 1980s. Other climatic and hydrologic indices, including stream discharge during low-flow months, do not display statistically significant trends. Consideration of potential specific causal mechanisms driven by rising temperatures suggests that melting of permafrost and falling water tables (from decreased recharge) are probable explanations for the increasing concentrations. The prospect of future widespread increases in dissolved solutes from mineralized watersheds is concerning given likely negative impacts on downstream ecosystems and water resources, and complications created for the establishment of attainable remediation objectives at mine sites.

Sensitivity of isoprene emissions estimated using MEGAN to the time resolution of input climate data

Directory of Open Access Journals (Sweden)

K. Ashworth

2010-02-01

Full Text Available We evaluate the effect of varying the temporal resolution of the input climate data on isoprene emission estimates generated by the community emissions model MEGAN (Model of Emissions of Gases and Aerosols from Nature. The estimated total global annual emissions of isoprene is reduced from 766 Tg y⁻¹ when using hourly input data to 746 Tg y⁻¹ (a reduction of 3% for daily average input data and 711 Tg y⁻¹ (down 7% for monthly average input data. The impact on a local scale can be more significant with reductions of up to 55% at some locations when using monthly average data compared with using hourly data. If the daily and monthly average temperature data are used without the imposition of a diurnal cycle the global emissions estimates fall by 27–32%, and local annual emissions by up to 77%. A similar pattern emerges if hourly isoprene fluxes are considered. In order to better simulate and predict isoprene emission rates using MEGAN, we show it is necessary to use temperature and radiation data resolved to one hour. Given the importance of land-atmosphere interactions in the Earth system and the low computational cost of the MEGAN algorithms, we recommend that chemistry-climate models and the new generation of Earth system models input biogenic emissions at the highest temporal resolution possible.

Climate-driven disparities among ecological interactions threaten kelp forest persistence.

Science.gov (United States)

Provost, Euan J; Kelaher, Brendan P; Dworjanyn, Symon A; Russell, Bayden D; Connell, Sean D; Ghedini, Giulia; Gillanders, Bronwyn M; Figueira, WillIAM; Coleman, Melinda A

2017-01-01

The combination of ocean warming and acidification brings an uncertain future to kelp forests that occupy the warmest parts of their range. These forests are not only subject to the direct negative effects of ocean climate change, but also to a combination of unknown indirect effects associated with changing ecological landscapes. Here, we used mesocosm experiments to test the direct effects of ocean warming and acidification on kelp biomass and photosynthetic health, as well as climate-driven disparities in indirect effects involving key consumers (urchins and rock lobsters) and competitors (algal turf). Elevated water temperature directly reduced kelp biomass, while their turf-forming competitors expanded in response to ocean acidification and declining kelp canopy. Elevated temperatures also increased growth of urchins and, concurrently, the rate at which they thinned kelp canopy. Rock lobsters, which are renowned for keeping urchin populations in check, indirectly intensified negative pressures on kelp by reducing their consumption of urchins in response to elevated temperature. Overall, these results suggest that kelp forests situated towards the low-latitude margins of their distribution will need to adapt to ocean warming in order to persist in the future. What is less certain is how such adaptation in kelps can occur in the face of intensifying consumptive (via ocean warming) and competitive (via ocean acidification) pressures that affect key ecological interactions associated with their persistence. If such indirect effects counter adaptation to changing climate, they may erode the stability of kelp forests and increase the probability of regime shifts from complex habitat-forming species to more simple habitats dominated by algal turfs. © 2016 John Wiley & Sons Ltd.

Climate change and health costs of air emissions from biofuels and gasoline

Science.gov (United States)

Hill, Jason; Polasky, Stephen; Nelson, Erik; Tilman, David; Huo, Hong; Ludwig, Lindsay; Neumann, James; Zheng, Haochi; Bonta, Diego

2009-01-01

Environmental impacts of energy use can impose large costs on society. We quantify and monetize the life-cycle climate-change and health effects of greenhouse gas (GHG) and fine particulate matter (PM2.5) emissions from gasoline, corn ethanol, and cellulosic ethanol. For each billion ethanol-equivalent gallons of fuel produced and combusted in the US, the combined climate-change and health costs are $469 million for gasoline, $472–952 million for corn ethanol depending on biorefinery heat source (natural gas, corn stover, or coal) and technology, but only $123–208 million for cellulosic ethanol depending on feedstock (prairie biomass, Miscanthus, corn stover, or switchgrass). Moreover, a geographically explicit life-cycle analysis that tracks PM2.5 emissions and exposure relative to U.S. population shows regional shifts in health costs dependent on fuel production systems. Because cellulosic ethanol can offer health benefits from PM2.5 reduction that are of comparable importance to its climate-change benefits from GHG reduction, a shift from gasoline to cellulosic ethanol has greater advantages than previously recognized. These advantages are critically dependent on the source of land used to produce biomass for biofuels, on the magnitude of any indirect land use that may result, and on other as yet unmeasured environmental impacts of biofuels. PMID:19188587

Control of spontaneous emission from a microwave-field-driven four-level atom in an anisotropic photonic crystal

Energy Technology Data Exchange (ETDEWEB)

Zhang, Duo, E-mail: zhangduo10@gmail.com [Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Electrical and Electronic Engineering, Wuhan Polytechnic University, Wuhan 430023 (China); Li, Jiahua, E-mail: huajia_li@163.com [Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China); Ding, Chunling; Yang, Xiaoxue [Wuhan National Laboratory for Optoelectronics and School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)

2012-05-21

The spontaneous emission properties of a microwave-field-driven four-level atom embedded in anisotropic double-band photonic crystals (PCs) are investigated. We discuss the influences of the band-edge positions, Rabi frequency and detuning of the microwave field on the emission spectrum. It is found that several interesting features such as spectral-line enhancement, spectral-line suppression, spectral-line overlap, and multi-peak structures can be observed in the spectra. The proposed scheme can be achieved by use of a microwave-coupled field into hyperfine levels in rubidium atom confined in a photonic crystal. These theoretical investigations may provide more degrees of freedom to manipulate the atomic spontaneous emission. -- Highlights: ► Spontaneous emission properties of an atom embedded in PCs are investigated. ► Spectral-line enhancement, suppression and overlapping are observed. ► The results provide more degrees of freedom to control atomic spontaneous emission.

Control of spontaneous emission from a microwave-field-driven four-level atom in an anisotropic photonic crystal

International Nuclear Information System (INIS)

Zhang, Duo; Li, Jiahua; Ding, Chunling; Yang, Xiaoxue

2012-01-01

The spontaneous emission properties of a microwave-field-driven four-level atom embedded in anisotropic double-band photonic crystals (PCs) are investigated. We discuss the influences of the band-edge positions, Rabi frequency and detuning of the microwave field on the emission spectrum. It is found that several interesting features such as spectral-line enhancement, spectral-line suppression, spectral-line overlap, and multi-peak structures can be observed in the spectra. The proposed scheme can be achieved by use of a microwave-coupled field into hyperfine levels in rubidium atom confined in a photonic crystal. These theoretical investigations may provide more degrees of freedom to manipulate the atomic spontaneous emission. -- Highlights: ► Spontaneous emission properties of an atom embedded in PCs are investigated. ► Spectral-line enhancement, suppression and overlapping are observed. ► The results provide more degrees of freedom to control atomic spontaneous emission.

Climate change and climate policy

International Nuclear Information System (INIS)

Alfsen, Knut H.; Kolshus, Hans H.; Torvanger, Asbjoern

2000-08-01

The climate issue is a great political and scientific challenge for several reasons: (1) There are many uncertain aspects of the climate problem, such as future emission of climate gases, the response of the climate system upon these gases, and the effects of climate changes. (2) It is probable, however, that anthropogenic emission of climate gases, deforestation etc. will cause noticeable climate changes in the future. This might be observed as increased frequency of extreme weather situations. This appears to be a greater threat than a gradual increase of temperature and precipitation. (3) Since the climate system is large and react only relatively slowly on changes in for instance the emission of climate gases, the climate problem can only be solved by means of long-term measures. (4) The climate changes may be irreversible. A rational short-term strategy is to ensure maximum flexibility, which can be done by ''slowing down'' (curtailing emissions) and by avoiding irreversible actions as much as possible. The long-term challenge is to develop an economically responsible alternative to the present fossil-based energy system that permits carbon-efficient technologies to compete on price with coal and unconventional oil and gas. Norway is in a special position by being a large exporter of fossil fuel and at the same time wanting to appear responsible in environmental matters. This combination may incur considerable expenses upon Norway and it is therefore important that environmental commitments like the Kyoto agreement can be honoured to the lowest possible cost. The costs can be minimized by: (1) minimizing the measure costs in Norway, (2) working to make the international quota price as low as possible, and (3) reducing the loss of petroleum income as much as possible. This report describes the earth's climate history, the forces behind climatic changes and what the prospects for the future look like. It also reviews what is being done to curtail the emission of

Climate-Driven Reshuffling of Species and Genes: Potential Conservation Roles for Species Translocations and Recombinant Hybrid Genotypes

Directory of Open Access Journals (Sweden)

Jon Mark Scriber

2013-12-01

Full Text Available Comprising 50%–75% of the world’s fauna, insects are a prominent part of biodiversity in communities and ecosystems globally. Biodiversity across all levels of biological classifications is fundamentally based on genetic diversity. However, the integration of genomics and phylogenetics into conservation management may not be as rapid as climate change. The genetics of hybrid introgression as a source of novel variation for ecological divergence and evolutionary speciation (and resilience may generate adaptive potential and diversity fast enough to respond to locally-altered environmental conditions. Major plant and herbivore hybrid zones with associated communities deserve conservation consideration. This review addresses functional genetics across multi-trophic-level interactions including “invasive species” in various ecosystems as they may become disrupted in different ways by rapid climate change. “Invasive genes” (into new species and populations need to be recognized for their positive creative potential and addressed in conservation programs. “Genetic rescue” via hybrid translocations may provide needed adaptive flexibility for rapid adaptation to environmental change. While concerns persist for some conservationists, this review emphasizes the positive aspects of hybrids and hybridization. Specific implications of natural genetic introgression are addressed with a few examples from butterflies, including transgressive phenotypes and climate-driven homoploid recombinant hybrid speciation. Some specific examples illustrate these points using the swallowtail butterflies (Papilionidae with their long-term historical data base (phylogeographical diversity changes and recent (3-decade climate-driven temporal and genetic divergence in recombinant homoploid hybrids and relatively recent hybrid speciation of Papilio appalachiensis in North America. Climate-induced “reshuffling” (recombinations of species composition, genotypes

Climate-Driven Reshuffling of Species and Genes: Potential Conservation Roles for Species Translocations and Recombinant Hybrid Genotypes.

Science.gov (United States)

Scriber, Jon Mark

2013-12-24

Comprising 50%-75% of the world's fauna, insects are a prominent part of biodiversity in communities and ecosystems globally. Biodiversity across all levels of biological classifications is fundamentally based on genetic diversity. However, the integration of genomics and phylogenetics into conservation management may not be as rapid as climate change. The genetics of hybrid introgression as a source of novel variation for ecological divergence and evolutionary speciation (and resilience) may generate adaptive potential and diversity fast enough to respond to locally-altered environmental conditions. Major plant and herbivore hybrid zones with associated communities deserve conservation consideration. This review addresses functional genetics across multi-trophic-level interactions including "invasive species" in various ecosystems as they may become disrupted in different ways by rapid climate change. "Invasive genes" (into new species and populations) need to be recognized for their positive creative potential and addressed in conservation programs. "Genetic rescue" via hybrid translocations may provide needed adaptive flexibility for rapid adaptation to environmental change. While concerns persist for some conservationists, this review emphasizes the positive aspects of hybrids and hybridization. Specific implications of natural genetic introgression are addressed with a few examples from butterflies, including transgressive phenotypes and climate-driven homoploid recombinant hybrid speciation. Some specific examples illustrate these points using the swallowtail butterflies (Papilionidae) with their long-term historical data base (phylogeographical diversity changes) and recent (3-decade) climate-driven temporal and genetic divergence in recombinant homoploid hybrids and relatively recent hybrid speciation of Papilio appalachiensis in North America. Climate-induced "reshuffling" (recombinations) of species composition, genotypes, and genomes may become

Effects of climate-induced changes in isoprene emissions after the eruption of Mount Pinatubo

Directory of Open Access Journals (Sweden)

P. J. Telford

2010-08-01

Full Text Available In the 1990s the rates of increase of greenhouse gas concentrations, most notably of methane, were observed to change, for reasons that have yet to be fully determined. This period included the eruption of Mt. Pinatubo and an El Niño warm event, both of which affect biogeochemical processes, by changes in temperature, precipitation and radiation. We examine the impact of these changes in climate on global isoprene emissions and the effect these climate dependent emissions have on the hydroxy radical, OH, the dominant sink for methane. We model a reduction of isoprene emissions in the early 1990s, with a maximum decrease of 40 Tg(C/yr in late 1992 and early 1993, a change of 9%. This reduction is caused by the cooler, drier conditions following the eruption of Mt. Pinatubo. Isoprene emissions are reduced both directly, by changes in temperature and a soil moisture dependent suppression factor, and indirectly, through reductions in the total biomass. The reduction in isoprene emissions causes increases of tropospheric OH which lead to an increased sink for methane of up to 5 Tg(CH₄/year, comparable to estimated source changes over the time period studied. There remain many uncertainties in the emission and oxidation of isoprene which may affect the exact size of this effect, but its magnitude is large enough that it should remain important.

Climate-wise choices in a world of oil abundance

Science.gov (United States)

Brandt, Adam R.; Masnadi, Mohammad S.; Englander, Jacob G.; Koomey, Jonathan; Gordon, Deborah

2018-04-01

Constrained oil supply has given way to abundance at a time when strong action on climate change is wavering. Recent innovation has pushed US oil production to all-time heights and driven oil prices lower. At the same time, attention to climate policy is wavering due to geopolitical upheaval. Nevertheless, climate-wise choices in the oil sector remain a priority, given oil’s large role in modern economies. Here we use a set of open-source models along with a detailed dataset comprising 75 global crude oils (~25% of global production) to estimate the effects of carbon intensity and oil demand on decadal scale oil-sector emissions. We find that oil resources are abundant relative to all projections of 21st century demand, due to large light-tight oil (LTO) and heavy oil/bitumen (HOB) resources. We then investigate the ‘barrel forward’ emissions from producing, refining, and consuming all products from a barrel of crude. These oil resources have diverse life-cycle-greenhouse gas (LC-GHG) emissions impacts, and median per-barrel emissions for unconventional resources vary significantly. Median HOB life cycle emissions are 1.5 times those of median LTO emissions, exceeding them by 200 kgCO2eq./bbl. We show that reducing oil LC-GHGs is a mitigation opportunity worth 10–50 gigatonnes CO2 eq. cumulatively by 2050. We discuss means to reduce oil sector LC-GHGs. Results point to the need for policymakers to address both oil supply and oil demand when considering options to reduce LC-GHGs.

Climate Implications of the Heterogeneity of Anthropogenic Aerosol Forcing

Science.gov (United States)

Persad, Geeta Gayatri

Short-lived anthropogenic aerosols are concentrated in regions of high human activity, where they interact with radiation and clouds, causing horizontally heterogeneous radiative forcing between polluted and unpolluted regions. Aerosols can absorb shortwave energy in the atmosphere, but deplete it at the surface, producing opposite radiative perturbations between the surface and atmosphere. This thesis investigates climate and policy implications of this horizontal and vertical heterogeneity of anthropogenic aerosol forcing, employing the Geophysical Fluid Dynamics Laboratory's AM2.1 and AM3 models, both at a global scale and using East Asia as a regional case study. The degree of difference between spatial patterns of climate change due to heterogeneous aerosol forcing versus homogeneous greenhouse gas forcing deeply impacts the detection, attribution, and prediction of regional climate change. This dissertation addresses a gap in current understanding of these two forcings' response pattern development, using AM2.1 historical forcing simulations. The results indicate that fast atmospheric and land-surface processes alone substantially homogenize the global pattern of surface energy flux response to heterogeneous aerosol forcing. Aerosols' vertical redistribution of energy significantly impacts regional climate, but is incompletely understood. It is newly identified here, via observations and historical and idealized forcing simulations, that increased aerosol-driven atmospheric absorption may explain half of East Asia's recent surface insolation decline. Further, aerosols' surface and atmospheric effects counteract each other regionally---atmospheric heating enhances summer monsoon circulation, while surface dimming suppresses it---but absorbing aerosols' combined effects reduce summer monsoon rainfall. This thesis constitutes the first vertical decomposition of aerosols' impacts in this high-emissions region and elucidates the monsoonal response to aerosols

Evolution of the earliest horses driven by climate change in the Paleocene-Eocene Thermal Maximum.

Science.gov (United States)

Secord, Ross; Bloch, Jonathan I; Chester, Stephen G B; Boyer, Doug M; Wood, Aaron R; Wing, Scott L; Kraus, Mary J; McInerney, Francesca A; Krigbaum, John

2012-02-24

Body size plays a critical role in mammalian ecology and physiology. Previous research has shown that many mammals became smaller during the Paleocene-Eocene Thermal Maximum (PETM), but the timing and magnitude of that change relative to climate change have been unclear. A high-resolution record of continental climate and equid body size change shows a directional size decrease of ~30% over the first ~130,000 years of the PETM, followed by a ~76% increase in the recovery phase of the PETM. These size changes are negatively correlated with temperature inferred from oxygen isotopes in mammal teeth and were probably driven by shifts in temperature and possibly high atmospheric CO(2) concentrations. These findings could be important for understanding mammalian evolutionary responses to future global warming.

A model of nitrous oxide evolution from soil driven by rainfall events. I - Model structure and sensitivity. II - Model applications

Science.gov (United States)

Changsheng, LI; Frolking, Steve; Frolking, Tod A.

1992-01-01

Simulations of N2O and CO2 emissions from soils were conducted with a rain-event driven, process-oriented model (DNDC) of nitrogen and carbon cycling processes in soils. The magnitude and trends of simulated N2O (or N2O + N2) and CO2 emissions were consistent with the results obtained in field experiments. The successful simulation of these emissions from the range of soil types examined demonstrates that the DNDC will be a useful tool for the study of linkages among climate, soil-atmosphere interactions, land use, and trace gas fluxes.

Photosynthesis-dependent isoprene emission from leaf to planet in a global carbon-chemistry-climate model

Science.gov (United States)

Unger, N.; Harper, K.; Zheng, Y.; Kiang, N. Y.; Aleinov, I.; Arneth, A.; Schurgers, G.; Amelynck, C.; Goldstein, A.; Guenther, A.; Heinesch, B.; Hewitt, C. N.; Karl, T.; Laffineur, Q.; Langford, B.; McKinney, K. A.; Misztal, P.; Potosnak, M.; Rinne, J.; Pressley, S.; Schoon, N.; Serça, D.

2013-10-01

We describe the implementation of a biochemical model of isoprene emission that depends on the electron requirement for isoprene synthesis into the Farquhar-Ball-Berry leaf model of photosynthesis and stomatal conductance that is embedded within a global chemistry-climate simulation framework. The isoprene production is calculated as a function of electron transport-limited photosynthesis, intercellular and atmospheric carbon dioxide concentration, and canopy temperature. The vegetation biophysics module computes the photosynthetic uptake of carbon dioxide coupled with the transpiration of water vapor and the isoprene emission rate at the 30 min physical integration time step of the global chemistry-climate model. In the model, the rate of carbon assimilation provides the dominant control on isoprene emission variability over canopy temperature. A control simulation representative of the present-day climatic state that uses 8 plant functional types (PFTs), prescribed phenology and generic PFT-specific isoprene emission potentials (fraction of electrons available for isoprene synthesis) reproduces 50% of the variability across different ecosystems and seasons in a global database of 28 measured campaign-average fluxes. Compared to time-varying isoprene flux measurements at 9 select sites, the model authentically captures the observed variability in the 30 min average diurnal cycle (R2 = 64-96%) and simulates the flux magnitude to within a factor of 2. The control run yields a global isoprene source strength of 451 TgC yr-1 that increases by 30% in the artificial absence of plant water stress and by 55% for potential natural vegetation.

Photosynthesis-dependent Isoprene Emission from Leaf to Planet in a Global Carbon-chemistry-climate Model

Science.gov (United States)

Unger, N.; Harper, K.; Zeng, Y.; Kiang, N. Y.; Alienov, I.; Arneth, A.; Schurgers, G.; Amelynck, C.; Goldstein, A.; Guenther, A.;

Photosynthesis-dependent isoprene emission from leaf to planet in a global carbon-chemistry-climate model

Energy Technology Data Exchange (ETDEWEB)

Unger, N.; Harper, K.; Zheng, Y.; Kiang, N. Y.; Aleinov, I.; Arneth, Almut; Schurgers, G.; Amelynck, C.; Goldstein, Allen H.; Guenther, Alex B.; Heinesch, B.; Hewitt, C. N.; Karl, T.; Laffineur, Q.; Langford, B.; McKinney, Karena A.; Misztal, P.; Potosnak, M.; Rinne, J.; Pressley, S.; Schoon, N.; Serca, D.

2013-10-22

We describe the implementation of a biochemical model of isoprene emission that depends on the electron requirement for isoprene synthesis into the Farquhar/Ball- Berry leaf model of photosynthesis and stomatal conductance that is embedded within a global chemistry-climate simulation framework. The isoprene production is calculated as a function of electron transport-limited photosynthesis, intercellular carbon dioxide concentration, and canopy temperature. The vegetation biophysics module computes the photosynthetic uptake of carbon dioxide coupled with the transpiration of water vapor and the isoprene emission rate at the 30 min physical integration time step of the global chemistry-climate model. In the model, the rate of carbon assimilation provides the dominant control on isoprene emission variability over canopy temperature. A control simulation representative of the present day climatic state that uses plant functional types (PFTs), prescribed phenology and generic PFT-specific isoprene emission potentials (fraction of electrons available for isoprene synthesis) reproduces 50% of the variability across different ecosystems and seasons in a global database of measured campaign-average fluxes. Compared to time-varying isoprene flux measurements at select sites, the model authentically captures the observed variability in the 30 min average diurnal cycle (R² = 64-96 %) and simulates the flux magnitude to within a factor of 2. The control run yields a global isoprene source strength of 451 TgC yr^-1 that increases by 30% in the artificial absence of plant water stress and by 55% for potential natural vegetation.

Climate-driven introduction of the Black Death and successive plague reintroductions into Europe.

Science.gov (United States)

Schmid, Boris V; Büntgen, Ulf; Easterday, W Ryan; Ginzler, Christian; Walløe, Lars; Bramanti, Barbara; Stenseth, Nils Chr

2015-03-10

The Black Death, originating in Asia, arrived in the Mediterranean harbors of Europe in 1347 CE, via the land and sea trade routes of the ancient Silk Road system. This epidemic marked the start of the second plague pandemic, which lasted in Europe until the early 19th century. This pandemic is generally understood as the consequence of a singular introduction of Yersinia pestis, after which the disease established itself in European rodents over four centuries. To locate these putative plague reservoirs, we studied the climate fluctuations that preceded regional plague epidemics, based on a dataset of 7,711 georeferenced historical plague outbreaks and 15 annually resolved tree-ring records from Europe and Asia. We provide evidence for repeated climate-driven reintroductions of the bacterium into European harbors from reservoirs in Asia, with a delay of 15 ± 1 y. Our analysis finds no support for the existence of permanent plague reservoirs in medieval Europe.

Climate-driven introduction of the Black Death and successive plague reintroductions into Europe

Science.gov (United States)

Büntgen, Ulf; Easterday, W. Ryan; Ginzler, Christian; Walløe, Lars; Bramanti, Barbara; Stenseth, Nils Chr.

2015-01-01

The Black Death, originating in Asia, arrived in the Mediterranean harbors of Europe in 1347 CE, via the land and sea trade routes of the ancient Silk Road system. This epidemic marked the start of the second plague pandemic, which lasted in Europe until the early 19th century. This pandemic is generally understood as the consequence of a singular introduction of Yersinia pestis, after which the disease established itself in European rodents over four centuries. To locate these putative plague reservoirs, we studied the climate fluctuations that preceded regional plague epidemics, based on a dataset of 7,711 georeferenced historical plague outbreaks and 15 annually resolved tree-ring records from Europe and Asia. We provide evidence for repeated climate-driven reintroductions of the bacterium into European harbors from reservoirs in Asia, with a delay of 15 ± 1 y. Our analysis finds no support for the existence of permanent plague reservoirs in medieval Europe. PMID:25713390

Effects of Climate Change on Global Food Production from SRES Emissions and Socioeconomic Scenarios

Data.gov (United States)

National Aeronautics and Space Administration — Effects of Climate Change on Global Food Production from SRES Emissions and Socioeconomic Scenarios is an update to a major crop modeling study by the NASA Goddard...

A fair compromise to break the climate impasse. A major economies forum approach to emissions reductions budgeting

Energy Technology Data Exchange (ETDEWEB)

Grasso, Marco [Univ. of Milan-Bicocca (Italy). International Environmental Policy; J. Roberts, Timmons [Brown Univ., Providence, RI (United States). Environmental Studies and Sociology; The Brookings Institution, Washington, DC (United States)

2013-04-15

Key messages of the study are: Given the stalemate in U.N. climate negotiations, the best arena to strike a workable deal is among the members the Major Economies Forum on Energy and Climate (MEF); The 13 MEF members—including the EU-27 (but not double-counting the four EU countries that are also individual members of the MEF)—account for 81.3 percent of all global emissions; This proposal devises a fair compromise to break the impasse to develop a science-based approach for fairly sharing the carbon budget in order to have a 75 percent chance of avoiding dangerous climate change; To increase the likelihood of a future climate agreement, carbon accounting must shift from production-based inventories to consumption-based ones; The shares of a carbon budget to stay below 2 deg C through 2050 are calculated by cumulative emissions since 1990, i.e. according to a short-horizon polluter pays principle, and national capability (income), and allocated to MEF members through emission rights. This proposed fair compromise addresses key concerns of major emitters; According to this accounting, no countries have negative carbon budgets, there is substantial time for greening major developing economies, and some developed countries need to institute very rapid reductions in emissions; and, To provide a 'green ladder' to developing countries and to ensure a fair global deal, it will be crucial to agree how to extend sufficient and predictable financial support and the rapid transfer of technology.

A Step towards Sustainable Society: The Awareness of Carbon Dioxide Emissions, Climate Change and Carbon Capture in Malaysia

OpenAIRE

Ghazali, Zulkipli; Zahid, Muhammad; Kee, Tan Siok; Ibrahim, M. Yussoff

2016-01-01

Public awareness is crucial to mitigate negative impacts on the environment. The aim of the study is to explore the level of public awareness in five states of Malaysia (Perak, Melaka, Johor, Pahang and Terengganu) regarding CO2 emissions, climate change and carbon capture and storage (CCS). A questionnaire floated for exploring public awareness regarding CO2 emissions, climate change and CCS. Based on the questionnaire data was collected from five states (Perak, Melaka, Johor, Pahang and Ter...

Climate and air pollution impacts on habitat suitability of Austrian forest ecosystems.

Science.gov (United States)

Dirnböck, Thomas; Djukic, Ika; Kitzler, Barbara; Kobler, Johannes; Mol-Dijkstra, Janet P; Posch, Max; Reinds, Gert Jan; Schlutow, Angela; Starlinger, Franz; Wamelink, Wieger G W

2017-01-01

Climate change and excess deposition of airborne nitrogen (N) are among the main stressors to floristic biodiversity. One particular concern is the deterioration of valuable habitats such as those protected under the European Habitat Directive. In future, climate-driven shifts (and losses) in the species potential distribution, but also N driven nutrient enrichment may threaten these habitats. We applied a dynamic geochemical soil model (VSD+) together with a novel niche-based plant response model (PROPS) to 5 forest habitat types (18 forest sites) protected under the EU Directive in Austria. We assessed how future climate change and N deposition might affect habitat suitability, defined as the capacity of a site to host its typical plant species. Our evaluation indicates that climate change will be the main driver of a decrease in habitat suitability in the future in Austria. The expected climate change will increase the occurrence of thermophilic plant species while decreasing cold-tolerant species. In addition to these direct impacts, climate change scenarios caused an increase of the occurrence probability of oligotrophic species due to a higher N immobilisation in woody biomass leading to soil N depletion. As a consequence, climate change did offset eutrophication from N deposition, even when no further reduction in N emissions was assumed. Our results show that climate change may have positive side-effects in forest habitats when multiple drivers of change are considered.

US surface ozone trends and extremes from 1980 to 2014: quantifying the roles of rising Asian emissions, domestic controls, wildfires, and climate

Science.gov (United States)

Lin, Meiyun; Horowitz, Larry W.; Payton, Richard; Fiore, Arlene M.; Tonnesen, Gail

2017-03-01

US surface O3 responds to varying global-to-regional precursor emissions, climate, and extreme weather, with implications for designing effective air quality control policies. We examine these conjoined processes with observations and global chemistry-climate model (GFDL-AM3) hindcasts over 1980-2014. The model captures the salient features of observed trends in daily maximum 8 h average O3: (1) increases over East Asia (up to 2 ppb yr-1), (2) springtime increases at western US (WUS) rural sites (0.2-0.5 ppb yr-1) with a baseline sampling approach, and (3) summertime decreases, largest at the 95th percentile, and wintertime increases in the 50th to 5th percentiles over the eastern US (EUS). Asian NOx emissions have tripled since 1990, contributing as much as 65 % to modeled springtime background O3 increases (0.3-0.5 ppb yr-1) over the WUS, outpacing O3 decreases attained via 50 % US NOx emission controls. Methane increases over this period contribute only 15 % of the WUS background O3 increase. Springtime O3 observed in Denver has increased at a rate similar to remote rural sites. During summer, increasing Asian emissions approximately offset the benefits of US emission reductions, leading to weak or insignificant observed O3 trends at WUS rural sites. Mean springtime WUS O3 is projected to increase by ˜ 10 ppb from 2010 to 2030 under the RCP8.5 global change scenario. While historical wildfire emissions can enhance summertime monthly mean O3 at individual sites by 2-8 ppb, high temperatures and the associated buildup of O3 produced from regional anthropogenic emissions contribute most to elevating observed summertime O3 throughout the USA. GFDL-AM3 captures the observed interannual variability of summertime EUS O3. However, O3 deposition sink to vegetation must be reduced by 35 % for the model to accurately simulate observed high-O3 anomalies during the severe drought of 1988. Regional NOx reductions alleviated the O3 buildup during the recent heat waves of 2011

Limited impact on decadal-scale climate change from increased use of natural gas.

Science.gov (United States)

McJeon, Haewon; Edmonds, Jae; Bauer, Nico; Clarke, Leon; Fisher, Brian; Flannery, Brian P; Hilaire, Jérôme; Krey, Volker; Marangoni, Giacomo; Mi, Raymond; Riahi, Keywan; Rogner, Holger; Tavoni, Massimo

2014-10-23

The most important energy development of the past decade has been the wide deployment of hydraulic fracturing technologies that enable the production of previously uneconomic shale gas resources in North America. If these advanced gas production technologies were to be deployed globally, the energy market could see a large influx of economically competitive unconventional gas resources. The climate implications of such abundant natural gas have been hotly debated. Some researchers have observed that abundant natural gas substituting for coal could reduce carbon dioxide (CO2) emissions. Others have reported that the non-CO2 greenhouse gas emissions associated with shale gas production make its lifecycle emissions higher than those of coal. Assessment of the full impact of abundant gas on climate change requires an integrated approach to the global energy-economy-climate systems, but the literature has been limited in either its geographic scope or its coverage of greenhouse gases. Here we show that market-driven increases in global supplies of unconventional natural gas do not discernibly reduce the trajectory of greenhouse gas emissions or climate forcing. Our results, based on simulations from five state-of-the-art integrated assessment models of energy-economy-climate systems independently forced by an abundant gas scenario, project large additional natural gas consumption of up to +170 per cent by 2050. The impact on CO2 emissions, however, is found to be much smaller (from -2 per cent to +11 per cent), and a majority of the models reported a small increase in climate forcing (from -0.3 per cent to +7 per cent) associated with the increased use of abundant gas. Our results show that although market penetration of globally abundant gas may substantially change the future energy system, it is not necessarily an effective substitute for climate change mitigation policy.

Does the Bush Administration's climate policy mean climate protection?

International Nuclear Information System (INIS)

Blanchard, Odile; Perkaus, James F.

2004-01-01

The paper analyzes the two major components of the Bush Administration's climate policy, namely an emission intensity target and a technology strategy. The question is whether those components will generate net emission reductions that will contribute to the stabilization of the greenhouse gas concentration at a safe level in the long run. It comes out that the Bush Administration climate policy does not guarantee any meaningful contribution to climate protection. The lenient emission intensity target set by the Administration will most likely allow near term emissions to grow. In the long run, the Bush Administration places a big bet on future climate-friendly technological breakthroughs to cost-effectively compensate for the current and near term net emission increases. But the outcomes of those technological developments are uncertain in terms of emission reduction potential, cost, and timing. The way towards enhanced climate protection will most likely not come from the policies of the current Administration, but rather from the growing concern about the climate issue in Congress and at the state, corporate and civil society levels. These combined forces may raise the playing field at the federal level in the near future

Assessment of methane emission and oxidation at Air Hitam Landfill site cover soil in wet tropical climate.

Science.gov (United States)

Abushammala, Mohammed F M; Basri, Noor Ezlin Ahmad; Elfithri, Rahmah

2013-12-01

Methane (CH₄) emissions and oxidation were measured at the Air Hitam sanitary landfill in Malaysia and were modeled using the Intergovernmental Panel on Climate Change waste model to estimate the CH₄ generation rate constant, k. The emissions were measured at several locations using a fabricated static flux chamber. A combination of gas concentrations in soil profiles and surface CH₄ and carbon dioxide (CO₂) emissions at four monitoring locations were used to estimate the CH₄ oxidation capacity. The temporal variations in CH₄ and CO₂ emissions were also investigated in this study. Geospatial means using point kriging and inverse distance weight (IDW), as well as arithmetic and geometric means, were used to estimate total CH₄ emissions. The point kriging, IDW, and arithmetic means were almost identical and were two times higher than the geometric mean. The CH₄ emission geospatial means estimated using the kriging and IDW methods were 30.81 and 30.49 gm(−2) day(−1), respectively. The total CH₄ emissions from the studied area were 53.8 kg day(−1). The mean of the CH₄ oxidation capacity was 27.5 %. The estimated value of k is 0.138 year(−1). Special consideration must be given to the CH₄ oxidation in the wet tropical climate for enhancing CH₄ emission reduction.

Climate-Smart Livestock Systems: An Assessment of Carbon Stocks and GHG Emissions in Nicaragua.

Directory of Open Access Journals (Sweden)

Lucía Gaitán

Full Text Available Livestock systems in the tropics can contribute to mitigate climate change by reducing greenhouse gas (GHG emissions and increasing carbon accumulation. We quantified C stocks and GHG emissions of 30 dual-purpose cattle farms in Nicaragua using farm inventories and lifecycle analysis. Trees in silvo-pastoral systems were the main C stock above-ground (16-24 Mg ha-1, compared with adjacent secondary forests (43 Mg C ha-1. We estimated that methane from enteric fermentation contributed 1.6 kg CO2-eq., and nitrous oxide from excreta 0.4 kg CO2-eq. per kg of milk produced. Seven farms that we classified as climate-smart agriculture (CSA out of 16 farms had highest milk yields (6.2 kg cow-1day-1 and lowest emissions (1.7 kg CO2-eq. per kg milk produced. Livestock on these farms had higher-quality diets, especially during the dry season, and manure was managed better. Increasing the numbers of CSA farms and improving CSA technology will require better enabling policy and incentives such as payments for ecosystem services.

Climate-Smart Livestock Systems: An Assessment of Carbon Stocks and GHG Emissions in Nicaragua.

Science.gov (United States)

Gaitán, Lucía; Läderach, Peter; Graefe, Sophie; Rao, Idupulapati; van der Hoek, Rein

2016-01-01

Livestock systems in the tropics can contribute to mitigate climate change by reducing greenhouse gas (GHG) emissions and increasing carbon accumulation. We quantified C stocks and GHG emissions of 30 dual-purpose cattle farms in Nicaragua using farm inventories and lifecycle analysis. Trees in silvo-pastoral systems were the main C stock above-ground (16-24 Mg ha-1), compared with adjacent secondary forests (43 Mg C ha-1). We estimated that methane from enteric fermentation contributed 1.6 kg CO2-eq., and nitrous oxide from excreta 0.4 kg CO2-eq. per kg of milk produced. Seven farms that we classified as climate-smart agriculture (CSA) out of 16 farms had highest milk yields (6.2 kg cow-1day-1) and lowest emissions (1.7 kg CO2-eq. per kg milk produced). Livestock on these farms had higher-quality diets, especially during the dry season, and manure was managed better. Increasing the numbers of CSA farms and improving CSA technology will require better enabling policy and incentives such as payments for ecosystem services.

Climate policy implications for agricultural water demand

Energy Technology Data Exchange (ETDEWEB)

Chaturvedi, Vaibhav [Joint Global Change Research Inst., College Park, MD (United States); Hejazi, Mohamad I. [Joint Global Change Research Inst., College Park, MD (United States); Edmonds, James A. [Joint Global Change Research Inst., College Park, MD (United States); Clarke, Leon E. [Joint Global Change Research Inst., College Park, MD (United States); Kyle, G. Page [Joint Global Change Research Inst., College Park, MD (United States); Davies, Evan [Univ. of Alberta, Edmonton, AB (Canada); Wise, Marshall A. [Joint Global Change Research Inst., College Park, MD (United States); Calvin, Katherine V. [Joint Global Change Research Inst., College Park, MD (United States)

2013-03-01

Energy, water and land are scarce resources, critical to humans. Developments in each affect the availability and cost of the others, and consequently human prosperity. Measures to limit greenhouse gas concentrations will inevitably exact dramatic changes on energy and land systems and in turn alter the character, magnitude and geographic distribution of human claims on water resources. We employ the Global Change Assessment Model (GCAM), an integrated assessment model to explore the interactions of energy, land and water systems in the context of alternative policies to limit climate change to three alternative levels: 2.5 Wm-2 (445 ppm CO2-e), 3.5 Wm-2 (535 ppm CO2-e) and 4.5 Wm-2 (645 ppm CO2-e). We explore the effects of two alternative land-use emissions mitigation policy options—one which taxes terrestrial carbon emissions equally with fossil fuel and industrial emissions, and an alternative which only taxes fossil fuel and industrial emissions but places no penalty on land-use change emissions. We find that increasing populations and economic growth could be anticipated to almost triple demand for water for agricultural systems across the century even in the absence of climate policy. In general policies to mitigate climate change increase agricultural demands for water still further, though the largest changes occur in the second half of the century, under both policy regimes. The two policies examined profoundly affected both the sources and magnitudes of the increase in irrigation water demands. The largest increases in agricultural irrigation water demand occurred in scenarios where only fossil fuel emissions were priced (but not land-use change emission) and were primarily driven by rapid expansion in bioenergy production. In these scenarios water demands were large relative to present-day total available water, calling into question whether it would be physically possible to produce the associated biomass energy. We explored the potential of improved

Methane emission from ruminants and solid waste: A critical analysis of baseline and mitigation projections for climate and policy studies

Science.gov (United States)

Matthews, E.

2012-12-01

Current and projected estimates of methane (CH4) emission from anthropogenic sources are numerous but largely unexamined or compared. Presented here is a critical appraisal of CH4 projections used in climate-chemistry and policy studies. We compare emissions for major CH4 sources from several groups, including our own new data and RCP projections developed for climate-chemistry models for the next IPCC Assessment Report (AR5). We focus on current and projected baseline and mitigation emissions from ruminant animals and solid waste that are both predicted to rise dramatically in coming decades, driven primarily by developing countries. For waste, drivers include increasing urban populations, higher per capita waste generation due to economic growth and increasing landfilling rates. Analysis of a new global data base detailing waste composition, collection and disposal indicates that IPCC-based methodologies and default data overestimate CH4 emission for the current period which cascades into substantial overestimates in future projections. CH4 emission from solid waste is estimated to be ~10-15 Tg CH4/yr currently rather than the ~35 Tg/yr often reported in the literature. Moreover, emissions from developing countries are unlikely to rise rapidly in coming decades because new management approaches, such as sanitary landfills, that would increase emissions are maladapted to infrastructures in these countries and therefore unlikely to be implemented. The low current emission associated with solid waste (~10 Tg), together with future modest growth, implies that mitigation of waste-related CH4 emission is a poor candidate for slowing global warming. In the case of ruminant animals (~90 Tg CH4/yr currently), the dominant assumption driving future trajectories of CH4 emission is a substantial increase in meat and dairy consumption in developing countries to be satisfied by growing animal populations. Unlike solid waste, current ruminant emissions among studies exhibit a

Developing countries are combating climate change. Actions in developing countries that slow growth in carbon emissions

International Nuclear Information System (INIS)

Reid, Walter V.; Goldemberg, Jose

1998-01-01

The role of developing countries in helping to solve the problem of climate change is increasingly a focus of political controversy. With levels of greenhouse gas emissions projected to exceed those of developed countries by 2020, some industrialized countries are calling on developing countries to take stronger action to meet the commitments they have made in the Framework Convention on Climate Change (FCCC). This review of recent policy changes in developing countries, however, suggests that they are already taking little appreciated steps that reduce rates of growth in carbon emissions. Indeed, since the 1992 signing of the FCCC, carbon emission savings in developing countries may be greater than those attained by industrialized countries. A major source of these gains can be attributed to energy price reforms that are likely to have led to substantial gains in production and end-use efficiency. (author)

Climate Benefits of Material Recycling: Inventory of Average Greenhouse Gas Emissions for Denmark, Norway and Sweden

DEFF Research Database (Denmark)

Hillman, Karl; Damgaard, Anders; Eriksson, Ola

The purpose of this project is to compare emissions of greenhouse gases from material recycling with those from virgin material production, both from a material supply perspective and from a recycling system perspective. The method for estimating emissions and climate benefits is based on a review......, followed by a selection, of the most relevant publications on life cycle assessment (LCA) of materials for use in Denmark, Norway and Sweden. The proposed averages show that emissions from material recycling are lower in both perspectives, comparing either material supply or complete recycling systems....... The results can be used by companies and industry associations in Denmark, Norway and Sweden to communicate the current climate benefits of material recycling in general. They may also contribute to discussions on a societal level, as long as their average and historic nature is recognised....

Influence of methane emissions and vehicle efficiency on the climate implications of heavy-duty natural gas trucks.

Science.gov (United States)

Camuzeaux, Jonathan R; Alvarez, Ramón A; Brooks, Susanne A; Browne, Joshua B; Sterner, Thomas

2015-06-02

While natural gas produces lower carbon dioxide emissions than diesel during combustion, if enough methane is emitted across the fuel cycle, then switching a heavy-duty truck fleet from diesel to natural gas can produce net climate damages (more radiative forcing) for decades. Using the Technology Warming Potential methodology, we assess the climate implications of a diesel to natural gas switch in heavy-duty trucks. We consider spark ignition (SI) and high-pressure direct injection (HPDI) natural gas engines and compressed and liquefied natural gas. Given uncertainty surrounding several key assumptions and the potential for technology to evolve, results are evaluated for a range of inputs for well-to-pump natural gas loss rates, vehicle efficiency, and pump-to-wheels (in-use) methane emissions. Using reference case assumptions reflecting currently available data, we find that converting heavy-duty truck fleets leads to damages to the climate for several decades: around 70-90 years for the SI cases, and 50 years for the more efficient HPDI. Our range of results indicates that these fuel switches have the potential to produce climate benefits on all time frames, but combinations of significant well-to-wheels methane emissions reductions and natural gas vehicle efficiency improvements would be required.

Modelling pesticide leaching under climate change: parameter vs. climate input uncertainty

Directory of Open Access Journals (Sweden)

K. Steffens

2014-02-01

Full Text Available Assessing climate change impacts on pesticide leaching requires careful consideration of different sources of uncertainty. We investigated the uncertainty related to climate scenario input and its importance relative to parameter uncertainty of the pesticide leaching model. The pesticide fate model MACRO was calibrated against a comprehensive one-year field data set for a well-structured clay soil in south-western Sweden. We obtained an ensemble of 56 acceptable parameter sets that represented the parameter uncertainty. Nine different climate model projections of the regional climate model RCA3 were available as driven by different combinations of global climate models (GCM, greenhouse gas emission scenarios and initial states of the GCM. The future time series of weather data used to drive the MACRO model were generated by scaling a reference climate data set (1970–1999 for an important agricultural production area in south-western Sweden based on monthly change factors for 2070–2099. 30 yr simulations were performed for different combinations of pesticide properties and application seasons. Our analysis showed that both the magnitude and the direction of predicted change in pesticide leaching from present to future depended strongly on the particular climate scenario. The effect of parameter uncertainty was of major importance for simulating absolute pesticide losses, whereas the climate uncertainty was relatively more important for predictions of changes of pesticide losses from present to future. The climate uncertainty should be accounted for by applying an ensemble of different climate scenarios. The aggregated ensemble prediction based on both acceptable parameterizations and different climate scenarios has the potential to provide robust probabilistic estimates of future pesticide losses.

Isoprene emissions over Asia 1979–2012: impact of climate and land-use changes

Energy Technology Data Exchange (ETDEWEB)

Stavrakou, T.; Müller, J. -F.; Bauwens, M.; De Smedt, I.; Van Roozendael, M.; Guenther, A.; Wild, M.; Xia, X.

2014-01-01

Due to the scarcity of observational constraints and the rapidly changing environment in East and Southeast Asia, isoprene emissions predicted by models are expected to bear substantial uncertainties. The aim of this study is to improve upon the existing bottom-up estimates, and to investigate the temporal evolution of the fluxes in Asia over 1979–2012. To this purpose, we calculate the hourly emissions at 0.5°×0.5° resolution using the MEGAN–MOHYCAN model driven by ECMWF ERA-Interim climatology. In order to remedy for known biases identified in previous studies, and to improve the simulation of interannual variability and trends in emissions, this study incorporates (i) changes in land use, including the rapid expansion of oil palms, (ii) meteorological variability according to ERA-Interim, (iii) long-term changes in solar radiation (dimming/brightening) constrained by surface network radiation measurements, and (iv) recent experimental evidence that South Asian tropical forests are much weaker isoprene emitters than previously assumed, and on the other hand, that oil palms have a strong isoprene emission capacity. These effects lead to a significant lowering (factor of 2) in the total isoprene fluxes over the studied domain, and to emission reductions reaching a factor of 3.5 in Southeast Asia. The bottom-up annual isoprene emissions for 2005 are estimated at 7.0, 4.8, 8.3, and 2.9 Tg in China, India, Indonesia and Malaysia, respectively. The isoprene flux anomaly over the whole domain and studied period is found to be strongly correlated with the Oceanic Niño Index (r = 0.73), with positive (negative) anomalies related to El Niño (La Niña) years. Changes in temperature and solar radiation are the major drivers of the interannual variability and trends in the emissions, except over semi-arid areas such as northwestern China, Pakistan and Kazakhstan, where soil moisture is by far the main cause of interannual emission changes. In our base simulation

Framing Climate Goals in Terms of Cumulative CO2-Forcing-Equivalent Emissions

Science.gov (United States)

Jenkins, S.; Millar, R. J.; Leach, N.; Allen, M. R.

2018-03-01

The relationship between cumulative CO2 emissions and CO2-induced warming is determined by the Transient Climate Response to Emissions (TCRE), but total anthropogenic warming also depends on non-CO2 forcing, complicating the interpretation of emissions budgets based on CO2 alone. An alternative is to frame emissions budgets in terms of CO2-forcing-equivalent (CO2-fe) emissions—the CO2 emissions that would yield a given total anthropogenic radiative forcing pathway. Unlike conventional "CO2-equivalent" emissions, these are directly related to warming by the TCRE and need to fall to zero to stabilize warming: hence, CO2-fe emissions generalize the concept of a cumulative carbon budget to multigas scenarios. Cumulative CO2-fe emissions from 1870 to 2015 inclusive are found to be 2,900 ± 600 GtCO2-fe, increasing at a rate of 67 ± 9.5 GtCO2-fe/yr. A TCRE range of 0.8-2.5°C per 1,000 GtC implies a total budget for 0.6°C of additional warming above the present decade of 880-2,750 GtCO2-fe, with 1,290 GtCO2-fe implied by the Coupled Model Intercomparison Project Phase 5 median response, corresponding to 19 years' CO2-fe emissions at the current rate.

Estimation of Pre-industrial Nitrous Oxide Emission from the Terrestrial Biosphere

Science.gov (United States)

Xu, R.; Tian, H.; Lu, C.; Zhang, B.; Pan, S.; Yang, J.

2015-12-01

Nitrous oxide (N2O) is currently the third most important greenhouse gases (GHG) after methane (CH4) and carbon dioxide (CO2). Global N2O emission increased substantially primarily due to reactive nitrogen (N) enrichment through fossil fuel combustion, fertilizer production, and legume crop cultivation etc. In order to understand how climate system is perturbed by anthropogenic N2O emissions from the terrestrial biosphere, it is necessary to better estimate the pre-industrial N2O emissions. Previous estimations of natural N2O emissions from the terrestrial biosphere range from 3.3-9.0 Tg N2O-N yr-1. This large uncertainty in the estimation of pre-industrial N2O emissions from the terrestrial biosphere may be caused by uncertainty associated with key parameters such as maximum nitrification and denitrification rates, half-saturation coefficients of soil ammonium and nitrate, N fixation rate, and maximum N uptake rate. In addition to the large estimation range, previous studies did not provide an estimate on preindustrial N2O emissions at regional and biome levels. In this study, we applied a process-based coupled biogeochemical model to estimate the magnitude and spatial patterns of pre-industrial N2O fluxes at biome and continental scales as driven by multiple input data, including pre-industrial climate data, atmospheric CO2 concentration, N deposition, N fixation, and land cover types and distributions. Uncertainty associated with key parameters is also evaluated. Finally, we generate sector-based estimates of pre-industrial N2O emission, which provides a reference for assessing the climate forcing of anthropogenic N2O emission from the land biosphere.

Biological soil crusts accelerate the nitrogen cycle through large NO and HONO emissions in drylands.

Science.gov (United States)

Weber, Bettina; Wu, Dianming; Tamm, Alexandra; Ruckteschler, Nina; Rodríguez-Caballero, Emilio; Steinkamp, Jörg; Meusel, Hannah; Elbert, Wolfgang; Behrendt, Thomas; Sörgel, Matthias; Cheng, Yafang; Crutzen, Paul J; Su, Hang; Pöschl, Ulrich

2015-12-15

Reactive nitrogen species have a strong influence on atmospheric chemistry and climate, tightly coupling the Earth's nitrogen cycle with microbial activity in the biosphere. Their sources, however, are not well constrained, especially in dryland regions accounting for a major fraction of the global land surface. Here, we show that biological soil crusts (biocrusts) are emitters of nitric oxide (NO) and nitrous acid (HONO). Largest fluxes are obtained by dark cyanobacteria-dominated biocrusts, being ∼20 times higher than those of neighboring uncrusted soils. Based on laboratory, field, and satellite measurement data, we obtain a best estimate of ∼1.7 Tg per year for the global emission of reactive nitrogen from biocrusts (1.1 Tg a(-1) of NO-N and 0.6 Tg a(-1) of HONO-N), corresponding to ∼20% of global nitrogen oxide emissions from soils under natural vegetation. On continental scales, emissions are highest in Africa and South America and lowest in Europe. Our results suggest that dryland emissions of reactive nitrogen are largely driven by biocrusts rather than the underlying soil. They help to explain enigmatic discrepancies between measurement and modeling approaches of global reactive nitrogen emissions. As the emissions of biocrusts strongly depend on precipitation events, climate change affecting the distribution and frequency of precipitation may have a strong impact on terrestrial emissions of reactive nitrogen and related climate feedback effects. Because biocrusts also account for a large fraction of global terrestrial biological nitrogen fixation, their impacts should be further quantified and included in regional and global models of air chemistry, biogeochemistry, and climate.

Time-dependent climate sensitivity and the legacy of anthropogenic greenhouse gas emissions.

Science.gov (United States)

Zeebe, Richard E

2013-08-20

Climate sensitivity measures the response of Earth's surface temperature to changes in forcing. The response depends on various climate processes that feed back on the initial forcing on different timescales. Understanding climate sensitivity is fundamental to reconstructing Earth's climatic history as well as predicting future climate change. On timescales shorter than centuries, only fast climate feedbacks including water vapor, lapse rate, clouds, and snow/sea ice albedo are usually considered. However, on timescales longer than millennia, the generally higher Earth system sensitivity becomes relevant, including changes in ice sheets, vegetation, ocean circulation, biogeochemical cycling, etc. Here, I introduce the time-dependent climate sensitivity, which unifies fast-feedback and Earth system sensitivity. I show that warming projections, which include a time-dependent climate sensitivity, exhibit an enhanced feedback between surface warming and ocean CO2 solubility, which in turn leads to higher atmospheric CO2 levels and further warming. Compared with earlier studies, my results predict a much longer lifetime of human-induced future warming (23,000-165,000 y), which increases the likelihood of large ice sheet melting and major sea level rise. The main point regarding the legacy of anthropogenic greenhouse gas emissions is that, even if the fast-feedback sensitivity is no more than 3 K per CO2 doubling, there will likely be additional long-term warming from slow climate feedbacks. Time-dependent climate sensitivity also helps explaining intense and prolonged warming in response to massive carbon release as documented for past events such as the Paleocene-Eocene Thermal Maximum.

Photosynthesis-dependent isoprene emission from leaf to planet in a global carbon-chemistry-climate model

Directory of Open Access Journals (Sweden)

N. Unger

2013-10-01

Full Text Available We describe the implementation of a biochemical model of isoprene emission that depends on the electron requirement for isoprene synthesis into the Farquhar–Ball–Berry leaf model of photosynthesis and stomatal conductance that is embedded within a global chemistry-climate simulation framework. The isoprene production is calculated as a function of electron transport-limited photosynthesis, intercellular and atmospheric carbon dioxide concentration, and canopy temperature. The vegetation biophysics module computes the photosynthetic uptake of carbon dioxide coupled with the transpiration of water vapor and the isoprene emission rate at the 30 min physical integration time step of the global chemistry-climate model. In the model, the rate of carbon assimilation provides the dominant control on isoprene emission variability over canopy temperature. A control simulation representative of the present-day climatic state that uses 8 plant functional types (PFTs, prescribed phenology and generic PFT-specific isoprene emission potentials (fraction of electrons available for isoprene synthesis reproduces 50% of the variability across different ecosystems and seasons in a global database of 28 measured campaign-average fluxes. Compared to time-varying isoprene flux measurements at 9 select sites, the model authentically captures the observed variability in the 30 min average diurnal cycle (R2 = 64–96% and simulates the flux magnitude to within a factor of 2. The control run yields a global isoprene source strength of 451 TgC yr−1 that increases by 30% in the artificial absence of plant water stress and by 55% for potential natural vegetation.

Impacts of transportation sector emissions on future U.S. air quality in a changing climate. Part I: Projected emissions, simulation design, and model evaluation.

Science.gov (United States)

Campbell, Patrick; Zhang, Yang; Yan, Fang; Lu, Zifeng; Streets, David

2018-07-01

Emissions from the transportation sector are rapidly changing worldwide; however, the interplay of such emission changes in the face of climate change are not as well understood. This two-part study examines the impact of projected emissions from the U.S. transportation sector (Part I) on ambient air quality in the face of climate change (Part II). In Part I of this study, we describe the methodology and results of a novel Technology Driver Model (see graphical abstract) that includes 1) transportation emission projections (including on-road vehicles, non-road engines, aircraft, rail, and ship) derived from a dynamic technology model that accounts for various technology and policy options under an IPCC emission scenario, and 2) the configuration/evaluation of a dynamically downscaled Weather Research and Forecasting/Community Multiscale Air Quality modeling system. By 2046-2050, the annual domain-average transportation emissions of carbon monoxide (CO), nitrogen oxides (NO x ), volatile organic compounds (VOCs), ammonia (NH 3 ), and sulfur dioxide (SO 2 ) are projected to decrease over the continental U.S. The decreases in gaseous emissions are mainly due to reduced emissions from on-road vehicles and non-road engines, which exhibit spatial and seasonal variations across the U.S. Although particulate matter (PM) emissions widely decrease, some areas in the U.S. experience relatively large increases due to increases in ship emissions. The on-road vehicle emissions dominate the emission changes for CO, NO x , VOC, and NH 3 , while emissions from both the on-road and non-road modes have strong contributions to PM and SO 2 emission changes. The evaluation of the baseline 2005 WRF simulation indicates that annual biases are close to or within the acceptable criteria for meteorological performance in the literature, and there is an overall good agreement in the 2005 CMAQ simulations of chemical variables against both surface and satellite observations. Copyright © 2018

Youth Climate Summits: Empowering & Engaging Youth to Lead on Climate Change

Science.gov (United States)

Kretser, J.

2017-12-01

The Wild Center's Youth Climate Summits is a program that engages youth in climate literacy from knowledge and understanding to developing action in their schools and communities. Each Youth Climate Summit is a one to three day event that brings students and teachers together to learn about climate change science, impacts and solutions at a global and local level. Through speakers, workshops and activities, the Summit culminates in a student-driven Climate Action Plan that can be brought back to schools and communities. The summits have been found to be powerful vehicles for inspiration, learning, community engagement and youth leadership development. Climate literacy with a focus on local climate impacts and solutions is a key component of the Youth Climate Summit. The project-based learning surrounding the creation of a unique, student driven, sustainability and Climate Action Plan promotes leadership skills applicable and the tools necessary for a 21st Century workforce. Student driven projects range from school gardens and school energy audits to working with NYS officials to commit to going 100% renewable electricty at the three state-owned downhill ski facilities. The summit model has been scaled and replicated in other communities in New York State, Vermont, Ohio, Michigan and Washington states as well as internationally in Finland, Germany and Sri Lanka.

Transient Climate Impacts for Scenarios of Aerosol Emissions from Asia: A Story of Coal versus Gas

Science.gov (United States)

Grandey, B. S.; Cheng, H.; Wang, C.

2014-12-01

Projections of anthropogenic aerosol emissions are uncertain. In Asia, it is possible that emissions may increase if business continues as usual, with economic growth driving an increase in coal burning. But it is also possible that emissions may decrease rapidly due to the widespread adoption of cleaner technology or a shift towards non-coal fuels, such as natural gas. In this study, the transient climate impacts of three aerosol emissions scenarios are investigated: an RCP4.5 (Representative Concentration Pathway 4.5) control; a scenario with reduced Asian anthropogenic aerosol emissions; and a scenario with enhanced Asian anthropogenic aerosol emissions. A coupled atmosphere-ocean configuration of CESM (Community Earth System Model), including CAM5 (Community Atmosphere Model version 5), is used. Enhanced Asian aerosol emissions are found to delay global mean warming by one decade at the end of the century. Aerosol-induced suppression of the East Asian and South Asian summer monsoon precipitation occurs. The enhanced Asian aerosol emissions also remotely impact precipitation in other parts of the world: over the Sahel, West African monsoon precipitation is suppressed; and over Australia, austral summer monsoon precipitation is enhanced. These remote impacts on precipitation are associated with a southward shift of the ITCZ. The aerosol-induced sea surface temperature (SST) response appears to play an important role in the precipitation changes over South Asia and Australia, but not over East Asia. These results indicate that energy production in Asia, through the consequent aerosol emissions and associated radiative effects, might significantly influence future climate both locally and globally.

Examination of a climate stabilization pathway via zero-emissions using Earth system models

International Nuclear Information System (INIS)

Nohara, Daisuke; Tsutsui, J; Watanabe, S; Tachiiri, K; Hajima, T; Okajima, H; Matsuno, T

2015-01-01

Long-term climate experiments up to the year 2300 have been conducted using two full-scale complex Earth system models (ESMs), CESM1(BGC) and MIROC-ESM, for a CO 2 emissions reduction pathway, termed Z650, where annual CO 2 emissions peak at 11 PgC in 2020, decline by 50% every 30 years, and reach zero in 2160. The results have been examined by focusing on the approximate linear relationship between the temperature increase and cumulative CO 2 emissions. Although the temperature increase is nearly proportional to the cumulative CO 2 emissions in both models, this relationship does not necessarily provide a robust basis for the restriction of CO 2 emissions because it is substantially modulated by non-CO 2 forcing. CO 2 -induced warming, estimated from the atmospheric CO 2 concentrations in the models, indicates an approximate compensation of nonlinear changes between fast-mode responses to concentration changes at less than 10 years and slow-mode response at more than 100 years due to the thermal inertia of the ocean. In this estimate, CESM1(BGC) closely approximates a linear trend of 1.7 °C per 1000 PgC, whereas MIROC-ESM shows a deviation toward higher temperatures after the emissions peak, from 1.8 °C to 2.4 °C per 1000 PgC over the range of 400–850 PgC cumulative emissions corresponding to years 2000–2050. The evolution of temperature under zero emissions, 2160–2300, shows a slight decrease of about 0.1 °C per century in CESM1(BGC), but remains almost constant in MIROC-ESM. The fast-mode response toward the equilibrium state decreases with a decrease in the airborne fraction owing to continued CO 2 uptake (carbon cycle inertia), whereas the slow-mode response results in more warming owing to continued heat uptake (thermal inertia). Several specific differences are noted between the two models regarding the degree of this compensation and in some key regional aspects associated with sustained warming and long-term climate risks. Overall, elevated

The contribution of China’s emissions to global climate forcing

Science.gov (United States)

Li, Bengang; Gasser, Thomas; Ciais, Philippe; Piao, Shilong; Tao, Shu; Balkanski, Yves; Hauglustaine, Didier; Boisier, Juan-Pablo; Chen, Zhuo; Huang, Mengtian; Li, Laurent Zhaoxin; Li, Yue; Liu, Hongyan; Liu, Junfeng; Peng, Shushi; Shen, Zehao; Sun, Zhenzhong; Wang, Rong; Wang, Tao; Yin, Guodong; Yin, Yi; Zeng, Hui; Zeng, Zhenzhong; Zhou, Feng

2016-03-01

Knowledge of the contribution that individual countries have made to global radiative forcing is important to the implementation of the agreement on “common but differentiated responsibilities” reached by the United Nations Framework Convention on Climate Change. Over the past three decades, China has experienced rapid economic development, accompanied by increased emission of greenhouse gases, ozone precursors and aerosols, but the magnitude of the associated radiative forcing has remained unclear. Here we use a global coupled biogeochemistry-climate model and a chemistry and transport model to quantify China’s present-day contribution to global radiative forcing due to well-mixed greenhouse gases, short-lived atmospheric climate forcers and land-use-induced regional surface albedo changes. We find that China contributes 10% ± 4% of the current global radiative forcing. China’s relative contribution to the positive (warming) component of global radiative forcing, mainly induced by well-mixed greenhouse gases and black carbon aerosols, is 12% ± 2%. Its relative contribution to the negative (cooling) component is 15% ± 6%, dominated by the effect of sulfate and nitrate aerosols. China’s strongest contributions are 0.16 ± 0.02 watts per square metre for CO2 from fossil fuel burning, 0.13 ± 0.05 watts per square metre for CH4, -0.11 ± 0.05 watts per square metre for sulfate aerosols, and 0.09 ± 0.06 watts per square metre for black carbon aerosols. China’s eventual goal of improving air quality will result in changes in radiative forcing in the coming years: a reduction of sulfur dioxide emissions would drive a faster future warming, unless offset by larger reductions of radiative forcing from well-mixed greenhouse gases and black carbon.

Regional impacts of climate change and atmospheric CO2 on future ocean carbon uptake: a multi model linear feedback analysis

International Nuclear Information System (INIS)

Roy, Tilla; Bopp, Laurent; Gehlen, Marion; Cadule, Patricia; Schneider, Birgit; Frolicher, Thomas L.; Segschneider, Joachim; Tjiputra, Jerry; Heinze, Christoph; Joos, Fortunat

2011-01-01

The increase in atmospheric CO 2 over this century depends on the evolution of the oceanic air-sea CO 2 uptake, which will be driven by the combined response to rising atmospheric CO 2 itself and climate change. Here, the future oceanic CO 2 uptake is simulated using an ensemble of coupled climate-carbon cycle models. The models are driven by CO 2 emissions from historical data and the Special Report on Emissions Scenarios (SRES) A2 high-emission scenario. A linear feedback analysis successfully separates the regional future (2010-2100) oceanic CO 2 uptake into a CO 2 -induced component, due to rising atmospheric CO 2 concentrations, and a climate-induced component, due to global warming. The models capture the observation based magnitude and distribution of anthropogenic CO 2 uptake. The distributions of the climate-induced component are broadly consistent between the models, with reduced CO 2 uptake in the sub polar Southern Ocean and the equatorial regions, owing to decreased CO 2 solubility; and reduced CO 2 uptake in the mid-latitudes, owing to decreased CO 2 solubility and increased vertical stratification. The magnitude of the climate-induced component is sensitive to local warming in the southern extra-tropics, to large freshwater fluxes in the extra-tropical North Atlantic Ocean, and to small changes in the CO 2 solubility in the equatorial regions. In key anthropogenic CO 2 uptake regions, the climate-induced component offsets the CO 2 - induced component at a constant proportion up until the end of this century. This amounts to approximately 50% in the northern extra-tropics and 25% in the southern extra-tropics and equatorial regions. Consequently, the detection of climate change impacts on anthropogenic CO 2 uptake may be difficult without monitoring additional tracers, such as oxygen. (authors)

Regional impacts of climate change and atmospheric CO2 on future ocean carbon uptake: a multi model linear feedback analysis

International Nuclear Information System (INIS)

Roy, Tilla; Bopp, Laurent; Gehlen, Marion; Cadule, Patricia

2011-01-01

The increase in atmospheric CO 2 over this century depends on the evolution of the oceanic air-sea CO 2 uptake, which will be driven by the combined response to rising atmospheric CO 2 itself and climate change. Here, the future oceanic CO 2 uptake is simulated using an ensemble of coupled climate-carbon cycle models. The models are driven by CO 2 emissions from historical data and the Special Report on Emissions Scenarios (SRES) A2 high-emission scenario. A linear feedback analysis successfully separates the regional future (2010-2100) oceanic CO 2 uptake into a CO 2 -induced component, due to rising atmospheric CO 2 concentrations, and a climate-induced component, due to global warming. The models capture the observation based magnitude and distribution of anthropogenic CO 2 uptake. The distributions of the climate-induced component are broadly consistent between the models, with reduced CO 2 uptake in the sub-polar Southern Ocean and the equatorial regions, owing to decreased CO 2 solubility; and reduced CO 2 uptake in the mid latitudes, owing to decreased CO 2 solubility and increased vertical stratification. The magnitude of the climate-induced component is sensitive to local warming in the southern extra tropics, to large freshwater fluxes in the extra tropical North Atlantic Ocean, and to small changes in the CO 2 solubility in the equatorial regions. In key anthropogenic CO 2 uptake regions, the climate-induced component offsets the CO 2 - induced component at a constant proportion up until the end of this century. This amounts to approximately 50% in the northern extra tropics and 25% in the southern extra tropics and equatorial regions. Consequently, the detection of climate change impacts on anthropogenic CO 2 uptake may be difficult without monitoring additional tracers, such as oxygen. (authors)

From Oil Crisis to Climate Change. Understanding CO2 Emission Trends in IEA Countries

International Nuclear Information System (INIS)

Unander, F.

2003-11-01

OECD CO2 emissions from fuel combustion increased 13% between 1990 and 2001. This signals an important shift since, over the 1973 to 1990 period, emissions only increased by 3.4%. As a result, CO2 emissions from energy use (fuel combustion) contributed 81.1% of total OECD greenhouse gas emissions in 2001 compared to 77.7% in 1990. As these figures make clear, reducing CO2 emissions from fuel combustion constitutes a key challenge to combat climate change. Developing and successfully implementing the most efficient policies for reducing CO2 emissions requires a good understanding of how factors such as income, prices, demography, economic structure, lifestyle, climate, energy efficiency and fuel mix affect energy use and resulting CO2 emissions. This paper presents selected results from the analysis of CO2 developments included in the IEA publication 'From Oil Crisis to Climate Challenge: 30 Years of Energy Use in IEA Countries'. The paper gives a brief overview of aggregate CO2 emission trends and of how recent developments in selected IEA countries compare to emissions levels implied by the Kyoto targets. A deeper understanding of the aggregate trends is provided by showing results from a decomposition analysis and by discussing developments in key end-use sectors. The full publication presents a more detailed analysis of how various factors have shaped energy use patterns and CO2 emissions since 1973. The analysis draws on a newly developed database with detailed information on energy use in the manufacturing, household, service and transport sectors. The database represents the most disaggregated information available on a consistent basis across countries and sectors. The study uses quantitative measures to illustrate the forces that drive or restrain energy use. These measures - or indicators - include: activities such as manufacturing output or heated-floor-area of homes; structural developments such as changes in manufacturing output mix or changes in the

Making of Croatian Low-Emission Development Strategy

International Nuclear Information System (INIS)

Bartle, B.; Herencic, L.; Kordic, Z.; Pasicko, R.; Vlasic, S.

2012-01-01

A Low-Emission Development Strategy (LEDS) is a national, high-level, comprehensive, long-term strategy, developed by domestic stakeholders, which aims at decoupling economic growth and social development from greenhouse gas (GHG) emissions growth. Croatia has begun to join the growing list of countries in the world that have already developed a long-term strategy for low-emissions development and thereby take the road of sustainable development. The 16th Conference of the Parties'' (COP), held in Cancun in December 2010, adopted the Cancun Agreements - a historic set of decisions laying the foundation to tackle climate change through a new post-2012 regime. The Cancun Agreements ''encourages governments to prepare low-carbon development strategies in the context of sustainable development.'' and ''realizes that addressing climate change requires a paradigm shift towards building a low-carbon society that offers substantial opportunities and ensures continued high growth and sustainable development''. Recently the European Commission adopted a Roadmap for transforming the European Union into a competitive low carbon economy by 2050. The Roadmap describes the cost-effective pathway to reach the EU's objective of cutting greenhouse gas emissions by 80-95% of 1990 levels by 2050. On the domestic level, the LEDS is a country-driven policy instrument for national decision making. The LEDS supports sector transformation through a national, economy-wide approach. On the international level, LEDS support the global goal of GHG emission reduction. The Croatian Ministry of Environmental and Nature Protection in cooperation with United Nations Development Programme (UNDP) Croatia will design and implement the Low-Emissions Development Strategy (LEDS) under project titled ''Supporting RBEC countries transition to low-emission development''. The LEDS merges climate change action with national sustainable development and helps to identify and prioritize nationally appropriate

Lithium availability in the EU27 for battery-driven vehicles : The impact of recycling and substitution on the confrontation between supply and demand until 2050

NARCIS (Netherlands)

Miedema, Jan H.; Moll, Henri C.

The adverse impacts of climate change are widely recognized as well as the importance of the mitigation of carbon dioxide (CO2). Battery driven vehicles are expected to have a bright future, since GHG emissions can be reduced. Lithium-ion (Li-ion) batteries appear to be the most promising, due to

Modeling climatic effects of anthropogenic CO2 emissions: Unknowns and uncertainties

Science.gov (United States)

Soon, W.; Baliunas, S.; Idso, S.; Kondratyev, K. Ya.; Posmentier, E. S.

2001-12-01

A likelihood of disastrous global environmental consequences has been surmised as a result of projected increases in anthropogenic greenhouse gas emissions. These estimates are based on computer climate modeling, a branch of science still in its infancy despite recent, substantial strides in knowledge. Because the expected anthropogenic climate forcings are relatively small compared to other background and forcing factors (internal and external), the credibility of the modeled global and regional responses rests on the validity of the models. We focus on this important question of climate model validation. Specifically, we review common deficiencies in general circulation model calculations of atmospheric temperature, surface temperature, precipitation and their spatial and temporal variability. These deficiencies arise from complex problems associated with parameterization of multiply-interacting climate components, forcings and feedbacks, involving especially clouds and oceans. We also review examples of expected climatic impacts from anthropogenic CO2 forcing. Given the host of uncertainties and unknowns in the difficult but important task of climate modeling, the unique attribution of observed current climate change to increased atmospheric CO2 concentration, including the relatively well-observed latest 20 years, is not possible. We further conclude that the incautious use of GCMs to make future climate projections from incomplete or unknown forcing scenarios is antithetical to the intrinsically heuristic value of models. Such uncritical application of climate models has led to the commonly-held but erroneous impression that modeling has proven or substantiated the hypothesis that CO2 added to the air has caused or will cause significant global warming. An assessment of the positive skills of GCMs and their use in suggesting a discernible human influence on global climate can be found in the joint World Meteorological Organisation and United Nations

Clean coal technologies and global climate change

International Nuclear Information System (INIS)

Long, R.S.

1993-01-01

The role for Clean Coal Technologies is discussed in the context of the global climate change debate. Global climate change is, of course as the name implies, a global issue. This clearly distinguishes this issue from acid rain or ozone non-attainment, which are regional in nature. Therefore, the issue requires a global perspective, one that looks at the issue not just from a US policy standpoint but from an international policy view. This includes the positions of other individual nations, trading blocks, common interest groups, and the evolving United Nations bureaucracy. It is assumed that as the global economy continues to grow, energy demand will also grow. With growth in economic activity and energy use, will come growth in worldwide greenhouse gas emissions, including growth in carbon dioxide (CO 2 ) emissions. Much of this growth will occur in developing economies which intend to fuel their growth with coal-fired power, especially China and India. Two basic premises which set out the boundaries of this topic are presented. First, there is the premise that global climate change is occurring, or is about to occur, and that governments must do something to mitigate the causes of climate change. Although this premise is highly rebuttable, and not based on scientific certainty, political science has driven it to the forefront of the debate. Second is the premise that advanced combustion CCTs, with their higher efficiencies, will result in lower CO 2 emissions, and hence lessen any contribution of greater coal use to potential global climate change. This promise is demonstrably true. This discussion focuses on recent and emerging public sector policy actions, which may in large part establish a new framework in which the private sector will find new challenges and new opportunities

Surface area changes of Himalayan ponds as a proxy of hydrological climate-driven fluctuations

Science.gov (United States)

Salerno, Franco; Thakuri, Sudeep; Guyennon, Nicolas; Viviano, Gaetano; Tartari, Gianni

2016-04-01

The meteorological measurements at high-elevations of the Himalayan range are scarce due to the harsh conditions of these environments which limit the suitable maintenance of weather stations. As a consequence, the meager knowledge on how the climate is changed in the last decades at Himalayan high-elevations sets a serious limit upon the interpretation of relationships between causes and recent observed effects on the cryosphere. Although the glaciers masses reduction in Himalaya is currently sufficiently well described, how changes in climate drivers (precipitation and temperature) have influenced the melting and shrinkage processes are less clear. Consequently, the uncertainty related to the recent past amplifies when future forecasts are done, both for climate and impacts. In this context, a substantial body of research has already demonstrated the high sensitivity of lakes and ponds to climate. Some climate-related signals are highly visible and easily measurable in lakes. For example, climate-driven fluctuations in lake surface area have been observed in many remote sites. On interior Tibetan Plateau the lake growth since the late 1990s is mainly attributed to increased regional precipitation and weakened evaporation. Differently, other authors attribute at the observed increases of lake surfaces at the enhanced glacier melting. In our opinion these divergences found in literature are due to the type of glacial lakes considered in the study and in particular their relationship with glaciers. In general, in Himalaya three types of glacial lakes can be distinguished: (i) lakes that are not directly connected with glaciers, but that may have a glacier located in their basin (unconnected glacial lakes); (ii) supraglacial lakes, which develop on the surface of the glacier downstream; or (iii) proglacial lakes, which are moraine-dammed lakes that are in contact with the glacier front. Some of these lakes store large quantities of water and are susceptible to GLOFs

Collaborative Project: The problem of bias in defining uncertainty in computationally enabled strategies for data-driven climate model development. Final Technical Report.

Energy Technology Data Exchange (ETDEWEB)

Huerta, Gabriel [Univ. of New Mexico, Albuquerque, NM (United States)

2016-05-10

The objective of the project is to develop strategies for better representing scientific sensibilities within statistical measures of model skill that then can be used within a Bayesian statistical framework for data-driven climate model development and improved measures of model scientific uncertainty. One of the thorny issues in model evaluation is quantifying the effect of biases on climate projections. While any bias is not desirable, only those biases that affect feedbacks affect scatter in climate projections. The effort at the University of Texas is to analyze previously calculated ensembles of CAM3.1 with perturbed parameters to discover how biases affect projections of global warming. The hypothesis is that compensating errors in the control model can be identified by their effect on a combination of processes and that developing metrics that are sensitive to dependencies among state variables would provide a way to select version of climate models that may reduce scatter in climate projections. Gabriel Huerta at the University of New Mexico is responsible for developing statistical methods for evaluating these field dependencies. The UT effort will incorporate these developments into MECS, which is a set of python scripts being developed at the University of Texas for managing the workflow associated with data-driven climate model development over HPC resources. This report reflects the main activities at the University of New Mexico where the PI (Huerta) and the Postdocs (Nosedal, Hattab and Karki) worked on the project.

Preindustrial nitrous oxide emissions from the land biosphere estimated by using a global biogeochemistry model

Science.gov (United States)

Xu, Rongting; Tian, Hanqin; Lu, Chaoqun; Pan, Shufen; Chen, Jian; Yang, Jia; Zhang, Bowen

2017-07-01

To accurately assess how increased global nitrous oxide (N2O) emission has affected the climate system requires a robust estimation of the preindustrial N2O emissions since only the difference between current and preindustrial emissions represents net drivers of anthropogenic climate change. However, large uncertainty exists in previous estimates of preindustrial N2O emissions from the land biosphere, while preindustrial N2O emissions on the finer scales, such as regional, biome, or sector scales, have not been well quantified yet. In this study, we applied a process-based Dynamic Land Ecosystem Model (DLEM) to estimate the magnitude and spatial patterns of preindustrial N2O fluxes at the biome, continental, and global level as driven by multiple environmental factors. Uncertainties associated with key parameters were also evaluated. Our study indicates that the mean of the preindustrial N2O emission was approximately 6.20 Tg N yr-1, with an uncertainty range of 4.76 to 8.13 Tg N yr-1. The estimated N2O emission varied significantly at spatial and biome levels. South America, Africa, and Southern Asia accounted for 34.12, 23.85, and 18.93 %, respectively, together contributing 76.90 % of global total emission. The tropics were identified as the major source of N2O released into the atmosphere, accounting for 64.66 % of the total emission. Our multi-scale estimates provide a robust reference for assessing the climate forcing of anthropogenic N2O emission from the land biosphere

Preindustrial nitrous oxide emissions from the land biosphere estimated by using a global biogeochemistry model

Directory of Open Access Journals (Sweden)

R. Xu

2017-07-01

Full Text Available To accurately assess how increased global nitrous oxide (N2O emission has affected the climate system requires a robust estimation of the preindustrial N2O emissions since only the difference between current and preindustrial emissions represents net drivers of anthropogenic climate change. However, large uncertainty exists in previous estimates of preindustrial N2O emissions from the land biosphere, while preindustrial N2O emissions on the finer scales, such as regional, biome, or sector scales, have not been well quantified yet. In this study, we applied a process-based Dynamic Land Ecosystem Model (DLEM to estimate the magnitude and spatial patterns of preindustrial N2O fluxes at the biome, continental, and global level as driven by multiple environmental factors. Uncertainties associated with key parameters were also evaluated. Our study indicates that the mean of the preindustrial N2O emission was approximately 6.20 Tg N yr−1, with an uncertainty range of 4.76 to 8.13 Tg N yr−1. The estimated N2O emission varied significantly at spatial and biome levels. South America, Africa, and Southern Asia accounted for 34.12, 23.85, and 18.93 %, respectively, together contributing 76.90 % of global total emission. The tropics were identified as the major source of N2O released into the atmosphere, accounting for 64.66 % of the total emission. Our multi-scale estimates provide a robust reference for assessing the climate forcing of anthropogenic N2O emission from the land biosphere

Interaction of the EU emissions Trading Directive with climate policy instrument in the Netherlands. Policy Brief

International Nuclear Information System (INIS)

Sijm, J.P.M.

2003-11-01

This policy brief presents an overview of the implications of the proposed EU Emissions Trading Scheme (EU ETS) for some selected energy and climate policy instruments in the Netherlands. It summarises the results of research that has been conducted by the Energy research Centre of the Netherlands (ECN) as part of the EU-funded project Interaction in EU Climate Policy

Extent and agenda of emission reduction policies in front of climate risks: lessons learned from integrated models

International Nuclear Information System (INIS)

Ambrosi, Ph.

2004-05-01

After having highlighted the main difficulties met when trying to take decisions on emission reductions (i.e. disequilibrium between short term action and long term dynamics, series of uncertainties, lack of a clear information on threats), this research aims at studying the extent and the agenda of CO 2 emission reduction efforts at a global scale. First, the author explores under various perspectives the relationship between the extent of climate change and the extent of its impacts and modes of analysis of climate policies. Then, he examines how different attitudes towards the climate risk are translated into recommendations for action which are obtained by always more complex models. In order to compare results, simulations are performed, based on optimal control models belonging to the RESPONSE family. Three different options or attitudes are then studied and assessed with RESPONSE: firstly, the uncertainty on impact and damage assessment is still too important to have confidence in present assessments; secondly, while being sceptical on damage assessment, more confidence is given to climate model results, and thirdly, an explicit representation of climate damages is used to introduce rationality issues in the debate on risks

Beamed neutron emission driven by laser accelerated light ions

Science.gov (United States)

Kar, S.; Green, A.; Ahmed, H.; Alejo, A.; Robinson, A. P. L.; Cerchez, M.; Clarke, R.; Doria, D.; Dorkings, S.; Fernandez, J.; Mirfayzi, S. R.; McKenna, P.; Naughton, K.; Neely, D.; Norreys, P.; Peth, C.; Powell, H.; Ruiz, J. A.; Swain, J.; Willi, O.; Borghesi, M.

2016-05-01

Highly anisotropic, beam-like neutron emission with peak flux of the order of 109 n/sr was obtained from light nuclei reactions in a pitcher-catcher scenario, by employing MeV ions driven by a sub-petawatt laser. The spatial profile of the neutron beam, fully captured for the first time by employing a CR39 nuclear track detector, shows a FWHM divergence angle of ˜ 70^\\circ , with a peak flux nearly an order of magnitude higher than the isotropic component elsewhere. The observed beamed flux of neutrons is highly favourable for a wide range of applications, and indeed for further transport and moderation to thermal energies. A systematic study employing various combinations of pitcher-catcher materials indicates the dominant reactions being d(p, n+p)1H and d(d,n)3He. Albeit insufficient cross-section data are available for modelling, the observed anisotropy in the neutrons’ spatial and spectral profiles is most likely related to the directionality and high energy of the projectile ions.

Modeling European ruminant production systems: facing the challenges of climate change

DEFF Research Database (Denmark)

Kipling, Richard Philip; Bannink, Andre; Bellocchi, Gianni

2016-01-01

Ruminant production systems are important producers of food, support rural communities and culture, and help to maintain a range of ecosystem services including the sequestering of carbon in grassland soils. However, these systems also contribute significantly to climate change through greenhouse...... gas (GHG) emissions, while intensification of production has driven biodiversity and nutrient loss, and soil degradation. Modeling can offer insights into the complexity underlying the relationships between climate change, management and policy choices, food production, and the maintenance...... of ecosystem services. This paper 1) provides an overview of how ruminant systems modeling supports the efforts of stakeholders and policymakers to predict, mitigate and adapt to climate change and 2) provides ideas for enhancing modeling to fulfil this role. Many grassland models can predict plant growth...

Biogeophysical Impacts of Land-Use Change on Climate Extremes in Low-Emission Scenarios: Results From HAPPI-Land

Science.gov (United States)

Hirsch, Annette L.; Guillod, Benoit P.; Seneviratne, Sonia I.; Beyerle, Urs; Boysen, Lena R.; Brovkin, Victor; Davin, Edouard L.; Doelman, Jonathan C.; Kim, Hyungjun; Mitchell, Daniel M.; Nitta, Tomoko; Shiogama, Hideo; Sparrow, Sarah; Stehfest, Elke; van Vuuren, Detlef P.; Wilson, Simon

2018-03-01

The impacts of land use have been shown to have considerable influence on regional climate. With the recent international commitment to limit global warming to well below 2°C, emission reductions need to be ambitious and could involve major land-use change (LUC). Land-based mitigation efforts to curb emissions growth include increasing terrestrial carbon sequestration through reforestation, or the adoption of bioenergy crops. These activities influence local climate through biogeophysical feedbacks, however, it is uncertain how important they are for a 1.5° climate target. This was the motivation for HAPPI-Land: the half a degree additional warming, prognosis, and projected impacts—land-use scenario experiment. Using four Earth system models, we present the first multimodel results from HAPPI-Land and demonstrate the critical role of land use for understanding the characteristics of regional climate extremes in low-emission scenarios. In particular, our results show that changes in temperature extremes due to LUC are comparable in magnitude to changes arising from half a degree of global warming. We also demonstrate that LUC contributes to more than 20% of the change in temperature extremes for large land areas concentrated over the Northern Hemisphere. However, we also identify sources of uncertainty that influence the multimodel consensus of our results including how LUC is implemented and the corresponding biogeophysical feedbacks that perturb climate. Therefore, our results highlight the urgent need to resolve the challenges in implementing LUC across models to quantify the impacts and consider how LUC contributes to regional changes in extremes associated with sustainable development pathways.

Climate and air pollution impacts on habitat suitability of Austrian forest ecosystems

Science.gov (United States)

Djukic, Ika; Kitzler, Barbara; Kobler, Johannes; Mol-Dijkstra, Janet P.; Posch, Max; Reinds, Gert Jan; Schlutow, Angela; Starlinger, Franz; Wamelink, Wieger G. W.

2017-01-01

Climate change and excess deposition of airborne nitrogen (N) are among the main stressors to floristic biodiversity. One particular concern is the deterioration of valuable habitats such as those protected under the European Habitat Directive. In future, climate-driven shifts (and losses) in the species potential distribution, but also N driven nutrient enrichment may threaten these habitats. We applied a dynamic geochemical soil model (VSD+) together with a novel niche-based plant response model (PROPS) to 5 forest habitat types (18 forest sites) protected under the EU Directive in Austria. We assessed how future climate change and N deposition might affect habitat suitability, defined as the capacity of a site to host its typical plant species. Our evaluation indicates that climate change will be the main driver of a decrease in habitat suitability in the future in Austria. The expected climate change will increase the occurrence of thermophilic plant species while decreasing cold-tolerant species. In addition to these direct impacts, climate change scenarios caused an increase of the occurrence probability of oligotrophic species due to a higher N immobilisation in woody biomass leading to soil N depletion. As a consequence, climate change did offset eutrophication from N deposition, even when no further reduction in N emissions was assumed. Our results show that climate change may have positive side-effects in forest habitats when multiple drivers of change are considered. PMID:28898262

Climate and air pollution impacts on habitat suitability of Austrian forest ecosystems.

Directory of Open Access Journals (Sweden)

Thomas Dirnböck

Full Text Available Climate change and excess deposition of airborne nitrogen (N are among the main stressors to floristic biodiversity. One particular concern is the deterioration of valuable habitats such as those protected under the European Habitat Directive. In future, climate-driven shifts (and losses in the species potential distribution, but also N driven nutrient enrichment may threaten these habitats. We applied a dynamic geochemical soil model (VSD+ together with a novel niche-based plant response model (PROPS to 5 forest habitat types (18 forest sites protected under the EU Directive in Austria. We assessed how future climate change and N deposition might affect habitat suitability, defined as the capacity of a site to host its typical plant species. Our evaluation indicates that climate change will be the main driver of a decrease in habitat suitability in the future in Austria. The expected climate change will increase the occurrence of thermophilic plant species while decreasing cold-tolerant species. In addition to these direct impacts, climate change scenarios caused an increase of the occurrence probability of oligotrophic species due to a higher N immobilisation in woody biomass leading to soil N depletion. As a consequence, climate change did offset eutrophication from N deposition, even when no further reduction in N emissions was assumed. Our results show that climate change may have positive side-effects in forest habitats when multiple drivers of change are considered.

A unifying framework for metrics for aggregating the climate effect of different emissions

International Nuclear Information System (INIS)

Tol, Richard S J; Berntsen, Terje K; Fuglestvedt, Jan S; O’Neill, Brian C; Shine, Keith P

2012-01-01

Multi-gas approaches to climate change policies require a metric establishing ‘equivalences’ among emissions of various species. Climate scientists and economists have proposed four kinds of such metrics and debated their relative merits. We present a unifying framework that clarifies the relationships among them. We show, as have previous authors, that the global warming potential (GWP), used in international law to compare emissions of greenhouse gases, is a special case of the global damage potential (GDP), assuming (1) a finite time horizon, (2) a zero discount rate, (3) constant atmospheric concentrations, and (4) impacts that are proportional to radiative forcing. Both the GWP and GDP follow naturally from a cost–benefit framing of the climate change issue. We show that the global temperature change potential (GTP) is a special case of the global cost potential (GCP), assuming a (slight) fall in the global temperature after the target is reached. We show how the four metrics should be generalized if there are intertemporal spillovers in abatement costs, distinguishing between private (e.g., capital stock turnover) and public (e.g., induced technological change) spillovers. Both the GTP and GCP follow naturally from a cost-effectiveness framing of the climate change issue. We also argue that if (1) damages are zero below a threshold and (2) infinitely large above a threshold, then cost-effectiveness analysis and cost–benefit analysis lead to identical results. Therefore, the GCP is a special case of the GDP. The UN Framework Convention on Climate Change uses the GWP, a simplified cost–benefit concept. The UNFCCC is framed around the ultimate goal of stabilizing greenhouse gas concentrations. Once a stabilization target has been agreed under the convention, implementation is clearly a cost-effectiveness problem. It would therefore be more consistent to use the GCP or its simplification, the GTP. (letter)

Remote Sensing-Driven Climatic/Environmental Variables for Modelling Malaria Transmission in Sub-Saharan Africa

Directory of Open Access Journals (Sweden)

Osadolor Ebhuoma

2016-06-01

Full Text Available Malaria is a serious public health threat in Sub-Saharan Africa (SSA, and its transmission risk varies geographically. Modelling its geographic characteristics is essential for identifying the spatial and temporal risk of malaria transmission. Remote sensing (RS has been serving as an important tool in providing and assessing a variety of potential climatic/environmental malaria transmission variables in diverse areas. This review focuses on the utilization of RS-driven climatic/environmental variables in determining malaria transmission in SSA. A systematic search on Google Scholar and the Institute for Scientific Information (ISI Web of KnowledgeSM databases (PubMed, Web of Science and ScienceDirect was carried out. We identified thirty-five peer-reviewed articles that studied the relationship between remotely-sensed climatic variable(s and malaria epidemiological data in the SSA sub-regions. The relationship between malaria disease and different climatic/environmental proxies was examined using different statistical methods. Across the SSA sub-region, the normalized difference vegetation index (NDVI derived from either the National Oceanic and Atmospheric Administration (NOAA Advanced Very High Resolution Radiometer (AVHRR or Moderate-resolution Imaging Spectrometer (MODIS satellite sensors was most frequently returned as a statistically-significant variable to model both spatial and temporal malaria transmission. Furthermore, generalized linear models (linear regression, logistic regression and Poisson regression were the most frequently-employed methods of statistical analysis in determining malaria transmission predictors in East, Southern and West Africa. By contrast, multivariate analysis was used in Central Africa. We stress that the utilization of RS in determining reliable malaria transmission predictors and climatic/environmental monitoring variables would require a tailored approach that will have cognizance of the geographical/climatic

Remote Sensing-Driven Climatic/Environmental Variables for Modelling Malaria Transmission in Sub-Saharan Africa.

Science.gov (United States)

Ebhuoma, Osadolor; Gebreslasie, Michael

2016-06-14

Malaria is a serious public health threat in Sub-Saharan Africa (SSA), and its transmission risk varies geographically. Modelling its geographic characteristics is essential for identifying the spatial and temporal risk of malaria transmission. Remote sensing (RS) has been serving as an important tool in providing and assessing a variety of potential climatic/environmental malaria transmission variables in diverse areas. This review focuses on the utilization of RS-driven climatic/environmental variables in determining malaria transmission in SSA. A systematic search on Google Scholar and the Institute for Scientific Information (ISI) Web of Knowledge(SM) databases (PubMed, Web of Science and ScienceDirect) was carried out. We identified thirty-five peer-reviewed articles that studied the relationship between remotely-sensed climatic variable(s) and malaria epidemiological data in the SSA sub-regions. The relationship between malaria disease and different climatic/environmental proxies was examined using different statistical methods. Across the SSA sub-region, the normalized difference vegetation index (NDVI) derived from either the National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) or Moderate-resolution Imaging Spectrometer (MODIS) satellite sensors was most frequently returned as a statistically-significant variable to model both spatial and temporal malaria transmission. Furthermore, generalized linear models (linear regression, logistic regression and Poisson regression) were the most frequently-employed methods of statistical analysis in determining malaria transmission predictors in East, Southern and West Africa. By contrast, multivariate analysis was used in Central Africa. We stress that the utilization of RS in determining reliable malaria transmission predictors and climatic/environmental monitoring variables would require a tailored approach that will have cognizance of the geographical/climatic

Gravity wave-driven fluctuations in OH nightglow from an extended, dissipative emission region

International Nuclear Information System (INIS)

Schubert, G.; Walterscheid, R.L.; Hickey, M.P.

1991-01-01

The theory of gravity wave-driven fluctuations in the OH nightglow from an extended source region is generalized to account for effects of eddy kinematic viscosity v and eddy thermal diffusivity κ. In the nondiffusive case, the amplitudes and phases of vertically integrated normalized intensity (δI)/(bar I) and temperature (δT 1 )/(bar T 1 ) perturbations and vertically integrated Krassovsky's ratio (η) as functions of period are influenced by the upper limit of vertical integration of the extended source, especially at long periods when vertical wavelengths γ v are small. The effects, which include oscillations in (δT)/(bar I), (δT 1 )/(bar T 1 ), and (η), particularly at long periods, are due to constructive and destructive interference of nightglow signals from vertically separated levels of the OH emitting region that occur when γ v is comparable to or smaller than the thickness of the main emission region. The sensitivity of these ratios to the upper limit of vertical integration occurs because of the relatively small rate of decay of the intensity of OH emission with height above the peak emission level and the exponential growth with altitude of nondissipative gravity waves. Because eddy diffusion increases γ v , especially at long periods, and reduces wave growth with height compared with the case v = κ = 0, inclusion of eddy diffusion removes the sensitivity of (η) and the other ratios ot the maximum height of vertical integration. It is essential to account for both eddy diffusion and emission from the entire vertically extended emission region to correctly predict (η), (δI)/(bar I), and (δT 1 )/(bar T 1 ) at long gravity wave periods

Cross-site comparisons of concentration-discharge relationships reveal climate-driven chemostatic set points

Science.gov (United States)

Godsey, S.; Kirchner, J. W.

2017-12-01

Streamflow solute concentrations often vary predictably with flows, providing insight into processes controlling solute generation and export. Previous work by the authors showed that log-transformed concentration-discharge relationships of weathering-derived solutes in 59 headwater catchments had relatively low slopes, implying that these watersheds behaved almost like chemostats. That is, their rates of solute production and/or mobilization were nearly proportional to water fluxes, on both event and inter-annual time scales. Here we re-examine these findings using data from roughly 1000 catchments, ranging from ˜10 to >1,000,000 sq. km in drainage area, and spanning a wide range of lithologic and climatic settings.Concentration-discharge relationships among this much larger set of much larger catchments are broadly consistent with the chemostatic behavior described above. However, site-to-site variations in mean concentrations among these catchments are negatively correlated with long-term average precipitation and discharge, suggesting dilution of stream concentrations under long-term leaching of the critical zone. Thus, on event and inter-annual time scales, stream solute concentrations are chemostatically buffered by groundwater storage and fast chemical reactions (such as ion exchange), but on much longer time scales, the catchment's chemostatic "set point" is determined by climatically driven critical zone evolution. We present examples illustrating short-term and long-term controls on water quality consistent with variations in weather and climate, and discuss their implications.

Current climate and climate change over India as simulated by the Canadian Regional Climate Model

Science.gov (United States)

Alexandru, Adelina; Sushama, Laxmi

2015-08-01

The performance of the fifth generation of the Canadian Regional Climate Model (CRCM5) in reproducing the main climatic characteristics over India during the southwest (SW)-, post- and pre-monsoon seasons are presented in this article. To assess the performance of CRCM5, European Centre for Medium- Range Weather Forecasts (ECMWF) Re- Analysis (ERA- 40) and Interim re-analysis (ERA-Interim) driven CRCM5 simulation is compared against independent observations and reanalysis data for the 1971-2000 period. Projected changes for two future periods, 2041-2070 and 2071-2100, with respect to the 1971-2000 current period are assessed based on two transient climate change simulations of CRCM5 spanning the 1950-2100 period. These two simulations are driven by the Canadian Earth System Model version 2 (CanESM2) and the Max Planck Institute for Meteorology's Earth System Low Resolution Model (MPI-ESM-LR), respectively. The boundary forcing errors associated with errors in the driving global climate models are also studied by comparing the 1971-2000 period of the CanESM2 and MPI-ESM-LR driven simulations with that of the CRCM5 simulation driven by ERA-40/ERA-Interim. Results show that CRCM5 driven by ERA-40/ERA-Interim is in general able to capture well the temporal and spatial patterns of 2 m-temperature, precipitation, wind, sea level pressure, total runoff and soil moisture over India in comparison with available reanalysis and observations. However, some noticeable differences between the model and observational data were found during the SW-monsoon season within the domain of integration. CRCM5 driven by ERA-40/ERA-Interim is 1-2 °C colder than CRU observations and generates more precipitation over the Western Ghats and central regions of India, and not enough in the northern and north-eastern parts of India and along the Konkan west coast in comparison with the observed precipitation. The monsoon onset seems to be relatively well captured over the southwestern coast of

Climate-driven Sympatry does not Lead to Foraging Competition Between Adélie and Gentoo Penguins

Science.gov (United States)

Cimino, M. A.; Moline, M. A.; Fraser, W.; Patterson-Fraser, D.; Oliver, M. J.

2016-02-01

Climate-driven sympatry may lead to competition for food resources between species, population shifts and changes in ecosystem structure. Rapid warming in the West Antarctic Peninsula (WAP) is coincident with increasing gentoo penguin and decreasing Adélie penguin populations, suggesting that competition for food may exacerbate the Adélie penguin decline. At Palmer Station, we tested for foraging competition between these species by comparing their prey, Antarctic krill, distributions and penguin foraging behaviors on fine scales. To study these predator-prey dynamics, we simultaneously deployed penguin satellite transmitters, and a REMUS autonomous underwater vehicle that acoustically detected krill aggregations and measured physical and biological properties of the water column. We detected krill aggregations within the horizontal and vertical foraging ranges of Adélie and gentoo penguin. In the upper 100 m of the water column, the distribution of krill aggregations were mainly associated with CHL and light, suggesting that krill selected for habitats that balance the need to consume food and avoid predation. Adélie and gentoo penguins mainly had spatially segregated foraging areas but in areas of overlap, gentoo penguins switched foraging behavior by foraging at deeper depths, a strategy which limits competition with Adélie penguins. This suggests that climate-driven sympatry does not necessarily result in competitive exclusion. Contrary to a recent theory, which suggests that increased competition for krill is the major driver of Adélie penguin population declines, we suggest that declines in Adélie penguins along the WAP are more likely due to direct and indirect climate impacts on their life histories.

Particle-in-cell modeling of the nanosecond field emission driven discharge in pressurized hydrogen

Science.gov (United States)

Levko, Dmitry; Yatom, Shurik; Krasik, Yakov E.

2018-02-01

The high-voltage field-emission driven nanosecond discharge in pressurized hydrogen is studied using the one-dimensional Particle-in-Cell Monte Carlo collision model. It is obtained that the main part of the field-emitted electrons becomes runaway in the thin cathode sheath. These runaway electrons propagate the entire cathode-anode gap, creating rather dense (˜1012 cm-3) seeding plasma electrons. In addition, these electrons initiate a streamer propagating through this background plasma with a speed ˜30% of the speed of light. Such a high streamer speed allows the self-acceleration mechanism of runaway electrons present between the streamer head and the anode to be realized. As a consequence, the energy of runaway electrons exceeds the cathode-anode gap voltage. In addition, the influence of the field emission switching-off time is analyzed. It is obtained that this time significantly influences the discharge dynamics.

Impact of regional climate change and future emission scenarios on surface O3 and PM2.5 over India

Science.gov (United States)

Pommier, Matthieu; Fagerli, Hilde; Gauss, Michael; Simpson, David; Sharma, Sumit; Sinha, Vinay; Ghude, Sachin D.; Landgren, Oskar; Nyiri, Agnes; Wind, Peter

2018-01-01

is driven by increases in dust, particulate organic matter (OM) and secondary inorganic aerosols (SIAs), which are mainly affected by the change in precipitation, biogenic emissions and wind speed.The large increase in anthropogenic emissions has a larger impact than climate change, causing O3 and PM2.5 levels to increase by 13 and 67 % on average in the 2050s over the main part of India, respectively. By the 2030s, secondary inorganic aerosol is predicted to become the second largest contributor to PM2.5 in India, and the largest in the 2050s, exceeding OM and dust.

Climate change mitigation policy paradigms — national objectives and alignments

DEFF Research Database (Denmark)

Halsnæs, Kirsten; Garg, Amit; Christensen, John M.

2014-01-01

for discussing how a multi objective policy paradigm can contribute to future climate change mitigation. The paper includes country case studies from Brazil, Canada, China, the European Union (EU), India, Japan, Mexico, Nigeria, South Africa, South Korea and the United States covering renewable energy options......, industry, transportation, the residential sector and cross-sectoral policies. These countries and regions together contribute more than two thirds of global GHG emissions. The paper finds that policies that are nationally driven and that have multiple objectives, including climate-change mitigation, have...... been widely applied for decades in both developing countries and industrialised countries. Many of these policies have a long history, and adjustments have taken place based on experience and cost effectiveness concerns. Various energy and climate-change policy goals have worked together...

EU climate policy impact in 2020. With a focus on the effectiveness of emissions trading policy in an economic recession scenario

International Nuclear Information System (INIS)

Graus, W.; Sreenivasamurthy, U.; Wesselink, B.

2009-06-01

PBL's Environmental Balance 2009 provides information on the current status and trends of environmental and climate policies. Ecofys contributes to the climate policy section of the report by developing the following three indicators: (1) ex-post and ex-ante policy impacts until 2020 at EU level (wedge diagram); (2) business-as-usual emissions of EU ETS sectors until 2020, revised for the current economic recession; (3) a latest literature review of EUA (EU emission allowances) price band expected until 2020. Based on the latter two analyses, a brief note on the impact of the current economic recession on the effectiveness of the EU emission trading scheme until 2020 is presented.An economic recession of two years or longer will considerably decrease the effectiveness of the Emissions Trading Scheme (ETS) in stimulating low-carbon technologies. In order to meet EU climate targets in the longer term, new governmental policies will be needed to compensate for this.

Climate certificates

International Nuclear Information System (INIS)

1998-10-01

Reduced emissions of climate gases at the lowest cost require international cooperation in order to ensure that the most cost-efficient measures are taken. A market for emission rights is one way of achieving this. However, creating the right conditions for such a market to operate requires an unambiguous definition of the product to be traded. In this PM, the Swedish Power Association sketches out how such a product could be defined, and how a market for the resulting unambiguously defined product could be operated internationally, in parallel with other markets for energy products. Trade in climate certificates could become a joint EU approach to achieving common results within the field of climate policy. The main features of the proposal are as follows: Electricity producers would be allowed to issue climate certificates for electricity produced without climate-affecting emissions, e.g. in wind power plants. 1 kWh of electricity produced without emissions would entitle the utility to issue a climate certificate for 1 kWh. Electricity from power stations having low emissions, e.g. modern natural gas-fired plants, would entitle the utility to issue certificates in proportion to how much lower their emissions were in comparison with those from conventional coal-fired power stations. The number of certificates would be reduced by an individual coefficient, related directly to the quantity of climate-affecting emissions from the plant concerned. They would be traded and noted on markets in the various member countries. The certificates would not be nationally restricted, but could be traded across borders. Exchanges would be authorised by national authorities, in accordance with overall EU directives. These authorised exchanges would act as certification bodies, checking that certificates had been properly issued in accordance with a corresponding volume of electricity production. Electricity and certificates could be purchased from different suppliers. The

Impact of climate and land cover changes on tropospheric ozone air quality and public health in East Asia between 1980 and 2010

Science.gov (United States)

Fu, Y.; Tai, A. P. K.

2015-09-01

Understanding how historical climate and land cover changes have affected tropospheric ozone in East Asia would help constrain the large uncertainties associated with future East Asian air quality projections. We perform a series of simulations using a global chemical transport model driven by assimilated meteorological data and a suite of land cover and land use data to examine the public health effects associated with changes in climate, land cover, land use, and anthropogenic emissions between the 5-year periods 1981-1985 and 2007-2011 in East Asia. We find that between these two periods land cover change alone could lead to a decrease in summertime surface ozone by up to 4 ppbv in East Asia and ~ 2000 fewer ozone-related premature deaths per year, driven mostly by enhanced dry deposition resulting from climate- and CO2-induced increase in vegetation density, which more than offsets the effect of reduced isoprene emission arising from cropland expansion. Climate change alone could lead to an increase in summertime ozone by 2-10 ppbv in most regions of East Asia and ~ 6000 more premature deaths annually, mostly attributable to warming. The combined impacts (-2 to +12 ppbv) show that while the effect of climate change is more pronounced, land cover change could offset part of the climate effect and lead to a previously unknown public health benefit. While the changes in anthropogenic emissions remain the largest contributor to deteriorating ozone air quality in East Asia over the past 30 years, we show that climate change and land cover changes could lead to a substantial modification of ozone levels, and thus should come into consideration when formulating future air quality management strategies. We also show that the sensitivity of surface ozone to land cover change is more dependent on dry deposition than on isoprene emission in most of East Asia, leading to ozone responses that are quite distinct from that in North America, where most ozone

Impact of Active Climate Control Seats on Energy Use, Fuel Use, and CO2 Emissions

Energy Technology Data Exchange (ETDEWEB)

Kreutzer, Cory J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Rugh, John P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Titov, Eugene V [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kekelia, Bidzina [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-11-28

vehicle, corresponding to 4.0 grams of CO2/mile savings. Finally, the potential impact of 100 percent adoption of climate control seats on U.S. light-duty fleet A/C fuel use was calculated to be 1.3 billion gallons of gasoline annually with a corresponding CO2 emissions reduction of 12.7 million tons. Direct comparison of the impact of the CCS to the ventilated seat off-cycle credit was not possible because the NREL analysis calculated a combined car/truck savings and the baseline A/C CO2 emissions were higher than EPA. To enable comparison, the CCS national A/C CO2 emissions were split into car/truck components and the ventilated seat credit was scaled up. The split CO2 emissions savings due to the CCS were 3.5 g/mi for a car and 4.4 g/mi for a truck. The CCS saved an additional 2.0 g/mi and 2.5 g/mi over the adjusted ventilated seat credit for a car and truck, respectively.

Climate change driven plant-metal-microbe interactions.

Science.gov (United States)

Rajkumar, Mani; Prasad, Majeti Narasimha Vara; Swaminathan, Sandhya; Freitas, Helena

2013-03-01

Various biotic and abiotic stress factors affect the growth and productivity of crop plants. Particularly, the climatic and/or heavy metal stress influence various processes including growth, physiology, biochemistry, and yield of crops. Climatic changes particularly the elevated atmospheric CO₂ enhance the biomass production and metal accumulation in plants and help plants to support greater microbial populations and/or protect the microorganisms against the impacts of heavy metals. Besides, the indirect effects of climatic change (e.g., changes in the function and structure of plant roots and diversity and activity of rhizosphere microbes) would lead to altered metal bioavailability in soils and concomitantly affect plant growth. However, the effects of warming, drought or combined climatic stress on plant growth and metal accumulation vary substantially across physico-chemico-biological properties of the environment (e.g., soil pH, heavy metal type and its bio-available concentrations, microbial diversity, and interactive effects of climatic factors) and plant used. Overall, direct and/or indirect effects of climate change on heavy metal mobility in soils may further hinder the ability of plants to adapt and make them more susceptible to stress. Here, we review and discuss how the climatic parameters including atmospheric CO₂, temperature and drought influence the plant-metal interaction in polluted soils. Other aspects including the effects of climate change and heavy metals on plant-microbe interaction, heavy metal phytoremediation and safety of food and feed are also discussed. This review shows that predicting how plant-metal interaction responds to altering climatic change is critical to select suitable crop plants that would be able to produce more yields and tolerate multi-stress conditions without accumulating toxic heavy metals for future food security. Copyright © 2012 Elsevier Ltd. All rights reserved.

Examination of the optimal operation of building scale combined heat and power systems under disparate climate and GHG emissions rates

International Nuclear Information System (INIS)

Howard, B.; Modi, V.

2017-01-01

Highlights: • CHP attributable reductions, not viable by electric generation alone, are defined. • Simplified operating strategy heuristics are optimal under specific circumstances. • Phosphoric acid fuel cells yield the largest reductions except in the extremes. • Changes in baseline emissions affect the optimal system capacity and operating hours. - Abstract: This work aims to elucidate notions concerning the ideal operation and greenhouse gas (GHG) emissions benefits of combined heat and power (CHP) systems by investigating how various metrics change as a function of the GHG emissions from the underlying electricity source, building use type and climate. Additionally, a new term entitled “CHP Attributable” reductions is introduced to quantify the benefits from the simultaneous use of thermal and electric energy, removing benefits achieved solely from fuel switching and generating electricity more efficiently. The GHG emission benefits from implementing internal combustion engine, microturbines, and phosphoric acid (PA) fuel cell based CHP systems were evaluated through an optimization approach considering energy demands of prototypical hospital, office, and residential buildings in varied climates. To explore the effect of electric GHG emissions rates, the ideal operation of the CHP systems was evaluated under three scenarios: “High” GHG emissions rates, “Low” GHG emissions rates, and “Current” GHG emissions rate for a specific location. The analysis finds that PA fuel cells achieve the highest GHG emission reductions in most cases considered, though there are exceptions. Common heuristics, such as electric load following and thermal load following, are the optimal operating strategy under specific conditions. The optimal CHP capacity and operating hours both vary as a function of building type, climate and GHG emissions rates from grid electricity. GHG emissions reductions can be as high as 49% considering a PA fuel cell for a

Climate Impacts of Ozone and Sulfate Air Pollution from Specific Emissions Sectors and Regions

Science.gov (United States)

Unger, N.; Koch, D. M.; Shindell, D. T.; Streets, D. G.

2006-12-01

The secondary air pollutants ozone (O3) and sulfate aerosol are generated by human activities and affect the Earth's climate system. The global mean radiative forcings of these short-lived species depend on the location of the precursor gas emissions, which has so far prevented their incorporation into climate-motivated policy agreements. O3 and sulfate aerosol are strongly coupled through tropospheric photochemistry and yet air quality control efforts consider each species separately. Previous modeling work to assess climate impacts of O3 has focused on individual precursors, such as nitrogen oxides, even though policy action would target a particular sector. We use the G-PUCCINI atmospheric composition-climate model to isolate the O3 and sulfate direct radiative forcing impacts of 6 specific emissions sectors (industry, transport, power, domestic biofuel, domestic fossil fuel and biomass burning) from 7 geographic regions (North America, Europe, South Asia, East Asia, North Africa and the Middle East, Central and South Africa and South America) for the near future 2030 atmosphere. The goal of the study is to identify specific source sectors and regions that present the most effective opportunities to mitigate global warming. At 2030, the industry and power sectors dominate the sulfate forcing across all regions, with East Asia, South Asia and North Africa and Middle East contributing the largest sulfate forcings (-100 to 120 mWm-2). The transport sector represents an important O3 forcing from all regions ranging from 5 mWm-2 (Europe) to 12 mWm-2 (East Asia). Domestic biofuel O3 forcing is important for the East Asia (13 mWm-2), South Asia (7 mWm-2) and Central and South Africa (10 mWm-2) regions. Biomass burning contributes large O3 forcings for the Central and South Africa (15 mWm-2) and South America (11 mWm-2) regions. In addition, the power sector O3 forcings from East Asia (14 mWm-2) and South Asia (8 mWm-2) are also substantial. Considering the sum of the O

A data-driven approach to identify controls on global fire activity from satellite and climate observations (SOFIA V1

Directory of Open Access Journals (Sweden)

M. Forkel

2017-12-01

Full Text Available Vegetation fires affect human infrastructures, ecosystems, global vegetation distribution, and atmospheric composition. However, the climatic, environmental, and socioeconomic factors that control global fire activity in vegetation are only poorly understood, and in various complexities and formulations are represented in global process-oriented vegetation-fire models. Data-driven model approaches such as machine learning algorithms have successfully been used to identify and better understand controlling factors for fire activity. However, such machine learning models cannot be easily adapted or even implemented within process-oriented global vegetation-fire models. To overcome this gap between machine learning-based approaches and process-oriented global fire models, we introduce a new flexible data-driven fire modelling approach here (Satellite Observations to predict FIre Activity, SOFIA approach version 1. SOFIA models can use several predictor variables and functional relationships to estimate burned area that can be easily adapted with more complex process-oriented vegetation-fire models. We created an ensemble of SOFIA models to test the importance of several predictor variables. SOFIA models result in the highest performance in predicting burned area if they account for a direct restriction of fire activity under wet conditions and if they include a land cover-dependent restriction or allowance of fire activity by vegetation density and biomass. The use of vegetation optical depth data from microwave satellite observations, a proxy for vegetation biomass and water content, reaches higher model performance than commonly used vegetation variables from optical sensors. We further analyse spatial patterns of the sensitivity between anthropogenic, climate, and vegetation predictor variables and burned area. We finally discuss how multiple observational datasets on climate, hydrological, vegetation, and socioeconomic variables together with

A data-driven approach to identify controls on global fire activity from satellite and climate observations (SOFIA V1)

Science.gov (United States)

Forkel, Matthias; Dorigo, Wouter; Lasslop, Gitta; Teubner, Irene; Chuvieco, Emilio; Thonicke, Kirsten

2017-12-01

Vegetation fires affect human infrastructures, ecosystems, global vegetation distribution, and atmospheric composition. However, the climatic, environmental, and socioeconomic factors that control global fire activity in vegetation are only poorly understood, and in various complexities and formulations are represented in global process-oriented vegetation-fire models. Data-driven model approaches such as machine learning algorithms have successfully been used to identify and better understand controlling factors for fire activity. However, such machine learning models cannot be easily adapted or even implemented within process-oriented global vegetation-fire models. To overcome this gap between machine learning-based approaches and process-oriented global fire models, we introduce a new flexible data-driven fire modelling approach here (Satellite Observations to predict FIre Activity, SOFIA approach version 1). SOFIA models can use several predictor variables and functional relationships to estimate burned area that can be easily adapted with more complex process-oriented vegetation-fire models. We created an ensemble of SOFIA models to test the importance of several predictor variables. SOFIA models result in the highest performance in predicting burned area if they account for a direct restriction of fire activity under wet conditions and if they include a land cover-dependent restriction or allowance of fire activity by vegetation density and biomass. The use of vegetation optical depth data from microwave satellite observations, a proxy for vegetation biomass and water content, reaches higher model performance than commonly used vegetation variables from optical sensors. We further analyse spatial patterns of the sensitivity between anthropogenic, climate, and vegetation predictor variables and burned area. We finally discuss how multiple observational datasets on climate, hydrological, vegetation, and socioeconomic variables together with data-driven

Uncertainties in modelling CH4 emissions from northern wetlands in glacial climates: the role of vegetation parameters

Directory of Open Access Journals (Sweden)

J. van Huissteden

2011-10-01

Full Text Available Marine Isotope Stage 3 (MIS 3 interstadials are marked by a sharp increase in the atmospheric methane (CH4 concentration, as recorded in ice cores. Wetlands are assumed to be the major source of this CH4, although several other hypotheses have been advanced. Modelling of CH4 emissions is crucial to quantify CH4 sources for past climates. Vegetation effects are generally highly generalized in modelling past and present-day CH4 fluxes, but should not be neglected. Plants strongly affect the soil-atmosphere exchange of CH4 and the net primary production of the vegetation supplies organic matter as substrate for methanogens. For modelling past CH4 fluxes from northern wetlands, assumptions on vegetation are highly relevant since paleobotanical data indicate large differences in Last Glacial (LG wetland vegetation composition as compared to modern wetland vegetation. Besides more cold-adapted vegetation, Sphagnum mosses appear to be much less dominant during large parts of the LG than at present, which particularly affects CH4 oxidation and transport. To evaluate the effect of vegetation parameters, we used the PEATLAND-VU wetland CO2/CH4 model to simulate emissions from wetlands in continental Europe during LG and modern climates. We tested the effect of parameters influencing oxidation during plant transport (fox, vegetation net primary production (NPP, parameter symbol Pmax, plant transport rate (Vtransp, maximum rooting depth (Zroot and root exudation rate (fex. Our model results show that modelled CH4 fluxes are sensitive to fox and Zroot in particular. The effects of Pmax, Vtransp and fex are of lesser relevance. Interactions with water table modelling are significant for Vtransp. We conducted experiments with different wetland vegetation types for Marine Isotope Stage 3 (MIS 3 stadial and interstadial climates and the present-day climate, by coupling PEATLAND-VU to high resolution climate model simulations for Europe. Experiments assuming

Uncertainties in modelling CH4 emissions from northern wetlands in glacial climates: the role of vegetation parameters

Science.gov (United States)

Berrittella, C.; van Huissteden, J.

2011-10-01

Marine Isotope Stage 3 (MIS 3) interstadials are marked by a sharp increase in the atmospheric methane (CH4) concentration, as recorded in ice cores. Wetlands are assumed to be the major source of this CH4, although several other hypotheses have been advanced. Modelling of CH4 emissions is crucial to quantify CH4 sources for past climates. Vegetation effects are generally highly generalized in modelling past and present-day CH4 fluxes, but should not be neglected. Plants strongly affect the soil-atmosphere exchange of CH4 and the net primary production of the vegetation supplies organic matter as substrate for methanogens. For modelling past CH4 fluxes from northern wetlands, assumptions on vegetation are highly relevant since paleobotanical data indicate large differences in Last Glacial (LG) wetland vegetation composition as compared to modern wetland vegetation. Besides more cold-adapted vegetation, Sphagnum mosses appear to be much less dominant during large parts of the LG than at present, which particularly affects CH4 oxidation and transport. To evaluate the effect of vegetation parameters, we used the PEATLAND-VU wetland CO2/CH4 model to simulate emissions from wetlands in continental Europe during LG and modern climates. We tested the effect of parameters influencing oxidation during plant transport (fox), vegetation net primary production (NPP, parameter symbol Pmax), plant transport rate (Vtransp), maximum rooting depth (Zroot) and root exudation rate (fex). Our model results show that modelled CH4 fluxes are sensitive to fox and Zroot in particular. The effects of Pmax, Vtransp and fex are of lesser relevance. Interactions with water table modelling are significant for Vtransp. We conducted experiments with different wetland vegetation types for Marine Isotope Stage 3 (MIS 3) stadial and interstadial climates and the present-day climate, by coupling PEATLAND-VU to high resolution climate model simulations for Europe. Experiments assuming dominance of

Effects of emissions change, climate change and long-range transport on regional modeling of future U.S. particulate matter pollution and speciation

Science.gov (United States)

He, Hao; Liang, Xin-Zhong; Wuebbles, Donald J.

2018-04-01

This study investigates the future U.S. PM2.5 pollution under multiple emissions scenarios, climate states, and long-range transport (LRT) effects using the regional Community Multi-scale Air Quality (CMAQ) model integrated with a regional climate model. CMAQ with fixed chemical lateral boundary conditions (LBCs) successfully reproduces the present-day PM2.5 pollution and its major species in rural and suburban areas, but has some discrepancies in urban areas such as the Los Angeles Basin, where detailed emissions and meteorology conditions cannot be resolved by the 30 km grid. Its performance is slightly worsened when using dynamic chemical LBCs from global chemical transport model (CTM) simulations, which provide cleaner conditions into the CMAQ lateral boundaries. Under future Intergovernmental Panel on Climate Change (IPCC) emission scenarios, CMAQ projects large PM2.5 reductions (∼40% for A1B and ∼20% for A1Fi scenario) in the eastern United States, but slight to moderate increases (∼5% for A1B and ∼10% for A1Fi) in the western United States. The projected increases are particularly large (up to 30%) near the Mexico-U.S. border, suggesting that Mexico is a major source for future U.S. PM2.5 pollution. The effect from climate change alone is estimated to increase PM2.5 levels ubiquitously (∼5% for both A1B and A1Fi) over the United States, except for a small decrease in the Houston, Texas area, where anthropogenic non-methane volatile organic compounds (NMVOCs) emissions dominate. This climate penalty, however, is substantially smaller than effects of emissions change, especially in the eastern United States. Future PM2.5 pollution is affected substantially (up to -20%) by changes in SO2 emissions and moderately (3-5%) by changes in NOx and NH3 emissions. The long-range transport (LRT) effects, which are estimated by comparing CMAQ simulations with fixed and dynamic LBCs, are regional dependent, causing up to 10-20% decrease over the western United

The relationship between peak warming and cumulative CO2 emissions, and its use to quantify vulnerabilities in the carbon-climate-human system

International Nuclear Information System (INIS)

Raupach, Michael; Canadell, Josep G.; Ciais, Philippe; Friedlingstein, Pierre; Rayner, Peter J.; Trudinger, Catherine M.

2011-01-01

Interactions between the carbon cycle, climate and human societies are subject to several major vulnerabilities, broadly defined as factors contributing to the risk of harm from human-induced climate change. We assess five vulnerabilities: (1) effects of increasing CO 2 on the partition of anthropogenic carbon between atmospheric, land and ocean reservoirs; (2) effects of climate change (quantified by temperature) on CO 2 fluxes; (3) uncertainty in climate sensitivity; (4) non-CO 2 radiative forcing and (5) anthropogenic CO 2 emissions. Our analysis uses a physically based expression for Tp(Qp), the peak warming Tp associated with a cumulative anthropogenic CO 2 emission Qp to the time of peak warming. The approximations in this expression are evaluated using a non-linear box model of the carbon-climate system, forced with capped emissions trajectories described by an analytic form satisfying integral and smoothness constraints. The first four vulnerabilities appear as parameters that influence Tp(Qp), whereas the last appears through the independent variable. In terms of likely implications for Tp(Qp), the decreasing order of the first four vulnerabilities is: uncertainties in climate sensitivity, effects of non-CO 2 radiative forcing, effects of climate change on CO 2 fluxes and effects of increasing CO 2 on the partition of anthropogenic carbon. (authors)

Does extreme precipitation intensity depend on the emissions scenario?

Science.gov (United States)

Pendergrass, Angeline; Lehner, Flavio; Sanderson, Benjamin; Xu, Yangyang

2016-04-01

The rate of increase of global-mean precipitation per degree surface temperature increase differs for greenhouse gas and aerosol forcings, and therefore depends on the change in composition of the emissions scenario used to drive climate model simulations for the remainder of the century. We investigate whether or not this is also the case for extreme precipitation simulated by a multi-model ensemble driven by four realistic emissions scenarios. In most models, the rate of increase of maximum annual daily rainfall per degree global warming in the multi-model ensemble is statistically indistinguishable across the four scenarios, whether this extreme precipitation is calculated globally, over all land, or over extra-tropical land. These results indicate that, in most models, extreme precipitation depends on the total amount of warming and does not depend on emissions scenario, in contrast to mean precipitation.

Modeling global residential sector energy demand for heating and air conditioning in the context of climate change

International Nuclear Information System (INIS)

Isaac, Morna; Vuuren, Detlef P. van

2009-01-01

In this article, we assess the potential development of energy use for future residential heating and air conditioning in the context of climate change. In a reference scenario, global energy demand for heating is projected to increase until 2030 and then stabilize. In contrast, energy demand for air conditioning is projected to increase rapidly over the whole 2000-2100 period, mostly driven by income growth. The associated CO 2 emissions for both heating and cooling increase from 0.8 Gt C in 2000 to 2.2 Gt C in 2100, i.e. about 12% of total CO 2 emissions from energy use (the strongest increase occurs in Asia). The net effect of climate change on global energy use and emissions is relatively small as decreases in heating are compensated for by increases in cooling. However, impacts on heating and cooling individually are considerable in this scenario, with heating energy demand decreased by 34% worldwide by 2100 as a result of climate change, and air-conditioning energy demand increased by 72%. At the regional scale considerable impacts can be seen, particularly in South Asia, where energy demand for residential air conditioning could increase by around 50% due to climate change, compared with the situation without climate change

Climate change and climate policy; Klimaendringer og klimapolitikk

Energy Technology Data Exchange (ETDEWEB)

Alfsen, Knut H.; Kolshus, Hans H.; Torvanger, Asbjoern

2000-08-01

The climate issue is a great political and scientific challenge for several reasons: (1) There are many uncertain aspects of the climate problem, such as future emission of climate gases, the response of the climate system upon these gases, and the effects of climate changes. (2) It is probable, however, that anthropogenic emission of climate gases, deforestation etc. will cause noticeable climate changes in the future. This might be observed as increased frequency of extreme weather situations. This appears to be a greater threat than a gradual increase of temperature and precipitation. (3) Since the climate system is large and react only relatively slowly on changes in for instance the emission of climate gases, the climate problem can only be solved by means of long-term measures. (4) The climate changes may be irreversible. A rational short-term strategy is to ensure maximum flexibility, which can be done by ''slowing down'' (curtailing emissions) and by avoiding irreversible actions as much as possible. The long-term challenge is to develop an economically responsible alternative to the present fossil-based energy system that permits carbon-efficient technologies to compete on price with coal and unconventional oil and gas. Norway is in a special position by being a large exporter of fossil fuel and at the same time wanting to appear responsible in environmental matters. This combination may incur considerable expenses upon Norway and it is therefore important that environmental commitments like the Kyoto agreement can be honoured to the lowest possible cost. The costs can be minimized by: (1) minimizing the measure costs in Norway, (2) working to make the international quota price as low as possible, and (3) reducing the loss of petroleum income as much as possible. This report describes the earth's climate history, the forces behind climatic changes and what the prospects for the future look like. It also reviews what is being done

Emission pathways to achieve 2.0°C and 1.5°C climate targets

Science.gov (United States)

Su, Xuanming; Takahashi, Kiyoshi; Fujimori, Shinichiro; Hasegawa, Tomoko; Tanaka, Katsumasa; Kato, Etsushi; Shiogama, Hideo; Masui, Toshihiko; Emori, Seita

2017-06-01

We investigated the feasibilities of 2.0°C and 1.5°C climate targets by considering the abatement potentials of a full suite of greenhouse gases, pollutants, and aerosols. We revised the inter-temporal dynamic optimization model DICE-2013R by introducing three features as follows. First, we applied a new marginal abatement cost curve derived under moderate assumptions regarding future socioeconomic development—the Shared Socioeconomic Pathways 2 (SSP2) scenario. Second, we addressed emission abatement for not only industrial CO2 but also land-use CO2, CH4, N2O, halogenated gases, CO, volatile organic compounds, SOx, NOx, black carbon and organic carbon. Third, we improved the treatment of the non-CO2 components in the climate module based on MAGICC 6.0. We obtained the following findings: (1) It is important to address the individual emissions in an analysis of low stabilization scenarios because abating land-use CO2, non-CO2 and aerosol emissions also contributes to maintaining a low level of radiative forcing and substantially affects the climate costs. (2) The 2.0°C target can be efficiently reached under the assumptions of the SSP2 scenario. (3) The 1.5°C target can be met with early deep cuts under the assumption of a temperature overshoot, and it will triple the carbon price and double the mitigation cost compared with the 2.0°C case.

20th-century industrial black carbon emissions altered Arctic climate forcing.

Science.gov (United States)

McConnell, Joseph R; Edwards, Ross; Kok, Gregory L; Flanner, Mark G; Zender, Charles S; Saltzman, Eric S; Banta, J Ryan; Pasteris, Daniel R; Carter, Megan M; Kahl, Jonathan D W

2007-09-07

Black carbon (BC) from biomass and fossil fuel combustion alters chemical and physical properties of the atmosphere and snow albedo, yet little is known about its emission or deposition histories. Measurements of BC, vanillic acid, and non-sea-salt sulfur in ice cores indicate that sources and concentrations of BC in Greenland precipitation varied greatly since 1788 as a result of boreal forest fires and industrial activities. Beginning about 1850, industrial emissions resulted in a sevenfold increase in ice-core BC concentrations, with most change occurring in winter. BC concentrations after about 1951 were lower but increasing. At its maximum from 1906 to 1910, estimated surface climate forcing in early summer from BC in Arctic snow was about 3 watts per square meter, which is eight times the typical preindustrial forcing value.

Alternatives to the Global Warming Potential for Comparing Climate Impacts of Emissions of Greenhouse Gases

International Nuclear Information System (INIS)

Shine, Keith P.; Fuglestvedt, J.S.; Hailemariam, K.; Stuber, N.

2005-01-01

The Global Warming Potential (GWP) is used within the Kyoto Protocol to the United Nations Framework Convention on Climate Change as a metric for weighting the climatic impact of emissions of different greenhouse gases. The GWP has been subjected to many criticisms because of its formulation, but nevertheless it has retained some favour because of the simplicity of its design and application, and its transparency compared to proposed alternatives. Here, two new metrics are proposed, which are based on a simple analytical climate model. The first metric is called the Global Temperature Change Potential and represents the temperature change at a given time due to a pulse emission of a gas (GTPP); the second is similar but represents the effect of a sustained emission change (hence GTPS). Both GTPP and GTPS are presented as relative to the temperature change due to a similar emission change of a reference gas, here taken to be carbon dioxide. Both metrics are compared against an upwelling-diffusion energy balance model that resolves land and ocean and the hemispheres. The GTPP does not perform well, compared to the energy balance model, except for long-lived gases. By contrast, the GTPS is shown to perform well relative to the energy balance model, for gases with a wide variety of lifetimes. It is also shown that for time horizons in excess of about 100 years, the GTPS and GWP produce very similar results, indicating an alternative interpretation for the GWP. The GTPS retains the advantage of the GWP in terms of transparency, and the relatively small number of input parameters required for calculation. However, it has an enhanced relevance, as it is further down the cause-effect chain of the impacts of greenhouse gases emissions and has an unambiguous interpretation. It appears to be robust to key uncertainties and simplifications in its derivation and may be an attractive alternative to the GWP

Modeling particle emission and power flow in pulsed-power driven, nonuniform transmission lines

Directory of Open Access Journals (Sweden)

Nichelle Bruner

2008-04-01

Full Text Available Pulsed-power driven x-ray radiographic systems are being developed to operate at higher power in an effort to increase source brightness and penetration power. Essential to the design of these systems is a thorough understanding of electron power flow in the transmission line that couples the pulsed-power driver to the load. In this paper, analytic theory and fully relativistic particle-in-cell simulations are used to model power flow in several experimental transmission-line geometries fielded on Sandia National Laboratories’ upgraded Radiographic Integrated Test Stand [IEEE Trans. Plasma Sci. 28, 1653 (2000ITPSBD0093-381310.1109/27.901250]. Good agreement with measured electrical currents is demonstrated on a shot-by-shot basis for simulations which include detailed models accounting for space-charge-limited electron emission, surface heating, and stimulated particle emission. Resonant cavity modes related to the transmission-line impedance transitions are also shown to be excited by electron power flow. These modes can drive oscillations in the output power of the system, degrading radiographic resolution.

Climate change impact of livestock CH4 emission in India: Global temperature change potential (GTP) and surface temperature response.

Science.gov (United States)

Kumari, Shilpi; Hiloidhari, Moonmoon; Kumari, Nisha; Naik, S N; Dahiya, R P

2018-01-01

Two climate metrics, Global surface Temperature Change Potential (GTP) and the Absolute GTP (AGTP) are used for studying the global surface temperature impact of CH 4 emission from livestock in India. The impact on global surface temperature is estimated for 20 and 100 year time frames due to CH 4 emission. The results show that the CH 4 emission from livestock, worked out to 15.3 Tg in 2012. In terms of climate metrics GTP of livestock-related CH 4 emission in India in 2012 were 1030 Tg CO 2 e (GTP 20 ) and 62 Tg CO 2 e (GTP 100 ) at the 20 and 100 year time horizon, respectively. The study also illustrates that livestock-related CH 4 emissions in India can cause a surface temperature increase of up to 0.7mK and 0.036mK over the 20 and 100 year time periods, respectively. The surface temperature response to a year of Indian livestock emission peaks at 0.9mK in the year 2021 (9 years after the time of emission). The AGTP gives important information in terms of temperature change due to annual CH 4 emissions, which is useful when comparing policies that address multiple gases. Copyright © 2017 Elsevier Inc. All rights reserved.

Air pollution and associated human mortality: The role of air pollutant emissions, climate change and methane concentration increases during the industrial period

Science.gov (United States)

Fang, Y.; Naik, V.; Horowitz, L. W.; Mauzerall, D. L.

2012-12-01

Increases in surface ozone (O3) and fine particulate matter (≤ 2.5μm aerodynamic diameter, PM2.5) are associated with excess premature human mortalities. Here we estimate changes in surface O3 and PM2.5 since preindustrial (1860) times and the global present-day (2000) premature human mortalities associated with these changes. We go beyond previous work to analyze and differentiate the contribution of three factors: changes in emissions of short-lived air pollutants, climate change, and increased methane (CH4) concentrations, to air pollution levels and the associated premature mortalities. We use a coupled chemistry-climate model in conjunction with global population distributions in 2000 to estimate exposure attributable to concentration changes since 1860 from each factor. Attributable mortalities are estimated using health impact functions of long-term relative risk estimates for O3 and PM2.5 from the epidemiology literature. We find global mean surface PM2.5 and health-relevant O3 (defined as the maximum 6-month mean of 1-hour daily maximum O3 in a year) have increased by 8±0.16 μg/m3 and 30±0.16 ppbv, respectively, over this industrial period as a result of combined changes in emissions of air pollutants (EMIS), climate (CLIM) and CH4 concentrations (TCH4). EMIS, CLIM and TCH4 cause global average PM2.5 (O3) to change by +7.5±0.19 μg/m3 (+25±0.30 ppbv), +0.4±0.17 μg/m3 (+0.5±0.28 ppbv), and -0.02±0.01 μg/m3 (+4.3±0.33 ppbv), respectively. Total changes in PM2.5 are associated with 1.5 (95% confidence interval, CI, 1.0-2.5) million all-cause mortalities annually and in O3 are associated with 375 (95% CI, 129-592) thousand respiratory mortalities annually. Most air pollution mortality is driven by changes in emissions of short-lived air pollutants and their precursors (95% and 85% of mortalities from PM2.5 and O3 respectively). However, changing climate and increasing CH4 concentrations also increased premature mortality associated with air

Aviation and Climate - An updated list of status of research on the effects of climate emissions from aircraft; Luftfart og klima. En oppdatert oversikt over status for forskning paa klimaeffekter av utslipp fra fly

Energy Technology Data Exchange (ETDEWEB)

Lund, Marianne T.; Berntsen, Jan S.; Fuglestvedt, Jan S. [Center for international climate and environmental research, Oslo, (Norway)

2011-07-01

Today carries approximately 23,000 flights over 2.2 billion passengers annually. On a global basis air travel accounts for almost 2 to 2.5 percent of the total anthropogenic Co2 emissions. Domestic civil aviation in Norway emitted 1.05 million tonnes of Co2 in 2008, according to reporting to the United Nations Framework Convention on Climate Change (UNFCCC, 2011). Emissions from international aviation from Norwegian airports in 2008 was just under 1.2 million tonnes of Co2 (National Inventory Report, 2010). Aviation is a sector that has been growing: in Norway the emissions from domestic aviation increased by 55 percent from 1990 to 2008, and also globally emissions have increased. There has been an even more powerful increase in traffic, but this increase did not been steady: The development is closely linked to the economy and the reduction is observed in periods of economic downturn. New technology and streamlining flight patterns made aircraft more energy efficient, which has helped to reduce emissions, but it has not been enough to compensate for the strong growth in traffic. If this trend continues, the total emissions from aviation increase further. In addition to Co2 consists emissions from airplanes a variety of other components that affect the climate, either directly or indirectly through chemical and physical processes in the atmosphere. This is not unique to aviation, but also apply to other sectors. The impact is complex and complicated, some mechanisms provide a cooling, others warming. Some effects are regional and have a geographic (and per day) variation in radiative forcing. Regional heterogeneous forcing can potentially change temperature and pressure distribution in the atmosphere and hence circulation patterns. The various emissions also have very different lifetimes in the atmosphere and affects the climate of the different time scales. For a number of mechanisms providing climate change are the chemical and meteorological conditions in the

Memory effect driven emissions of persistent organic pollutants from industrial thermal processes, their implications and management: a review.

Science.gov (United States)

Trivedi, Jitendra; Majumdar, Deepanjan

2013-04-15

Memory effect is delayed emission of certain persistent organic pollutants (POPs). Many of the POP compounds viz. polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) get trapped in the particulate phase deposited in the flue transfer lines and air pollution control systems (equivalent to storage in the memory of a system) and released subsequently. Memory effect driven emission is a combination of real time emission and emission of stored compounds and so is not a true measure of actual real time emission. Memory effect is now realized to have existed for a long time but was not identified and understood until recently. Memory effect has several serious implications e.g. it wrongly depicts emission patterns of POPs; it makes compliance to stipulated emission standards difficult; it could lead to wrong calculations of emission factors and emission inventory estimates of a plant and leads to misinterpretation of efficacy of processes and air pollution control systems. Further, new PCDD/Fs may be formed in the trapped particulate phase via de novo synthesis and the new compounds may be emitted, thereby increasing total PCDD/F emissions, apart from altering the homologue pattern of PCDD/Fs in emissions. Memory effect could be minimized by judicious operational and management (O&M) procedures like optimizing combustion, minimizing unnecessary halts in operations, periodical cleaning of flue transfer lines, application of inhibitors etc. Copyright © 2013 Elsevier Ltd. All rights reserved.

Co-benefits of climate policies: a potential keystone of climate negotiations?

International Nuclear Information System (INIS)

Cassen, Christophe; Guivarch, Celine; Lecocq, Franck

2015-01-01

This paper analyzes the challenges related to the assessment of co-benefits of climate policies underpinned by the implementation of multi-objective policies which seek synergies between climate policies and other development objectives (poverty alleviation, employment, health etc.). The analysis highlights the increasing interest in co-benefits in the latest 5. IPCC report, in particular by integrated models. Nevertheless, the quantified evaluation of co-benefits is still confronted to several methodological limitations which reduce the scope of co-benefits, particularly at the global level. In a growing context of climate-development approaches in climate negotiations, this article insists on the need to also assess co-benefits of other policies which induce a significant part of GHG emissions. Considering climate policies focused only on Greenhouse Gases emissions reduction limits the range of policy instruments to carbon taxation, tradable carbon emissions permits or dedicated mitigation and adaptation funds. This also hinders the integration of climate objectives in non-climate policies. Analyzing impacts of development policies on Green Gases emissions in the form of co-benefits requires to broaden the range of policy instruments and to take into account other drivers of emissions such as land dynamics. Including these mechanisms in integrated models therefore represents new scientific frontiers for integrated models in the coming years

Constraining estimates of methane emissions from Arctic permafrost regions with CARVE

Science.gov (United States)

Chang, R. Y.; Karion, A.; Sweeney, C.; Henderson, J.; Mountain, M.; Eluszkiewicz, J.; Luus, K. A.; Lin, J. C.; Dinardo, S.; Miller, C. E.; Wofsy, S. C.

2013-12-01

Permafrost in the Arctic contains large carbon pools that are currently non-labile, but can be released to the atmosphere as polar regions warm. In order to predict future climate scenarios, we need to understand the emissions of these greenhouse gases under varying environmental conditions. This study presents in-situ measurements of methane made on board an aircraft during the Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE), which sampled over the permafrost regions of Alaska. Using measurements from May to September 2012, seasonal emission rate estimates of methane from tundra are constrained using the Stochastic Time-Inverted Lagrangian Transport model, a Lagrangian particle dispersion model driven by custom polar-WRF fields. Preliminary results suggest that methane emission rates have not greatly increased since the Arctic Boundary Layer Experiment conducted in southwest Alaska in 1988.

Climate plan 2004; Plan climat 2004

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

The Climate Plan is an action plan drawn up by the French Government to respond to the climate change challenge, first by 2010 (complying with the Kyoto Protocol target), and, secondly, beyond this date. Projections for France show that national emissions could be 10% higher than the Kyoto target in 2010 if no measures are taken. This is particularly due to increasing emissions in the sectors affecting daily life (residential-tertiary sectors, transport, etc.). For this reason, the Climate Plan contains measures affecting all sectors of the economy and the daily life of all French citizens with a view to economizing the equivalent of 54 million tonnes of CO{sub 2} each year by the year 2010, which will help to reverse the trend significantly. Beyond 2010, the Climate Plan sets out a strategy for technological research which will enable France to meet a target of reducing greenhouse gas emissions four or fivefold by 2050. (author)

Environmental Concern, Social Capital and the Social Context of Tailpipe Emissions-Related Knowledge in Northern Climates

Science.gov (United States)

2012-06-30

Approximately a quarter of all greenhouse gases originate from motor vehicle tailpipe emissions (Intergovernmental Panel on Climate Change, 2007). Along with reducing household energy usage, changes in transportation behavior would have the most dire...

Assessing climate change impacts, benefits of mitigation, and uncertainties on major global forest regions under multiple socioeconomic and emissions scenarios

Science.gov (United States)

John B Kim; Erwan Monier; Brent Sohngen; G Stephen Pitts; Ray Drapek; James McFarland; Sara Ohrel; Jefferson Cole

2016-01-01

We analyze a set of simulations to assess the impact of climate change on global forests where MC2 dynamic global vegetation model (DGVM) was run with climate simulations from the MIT Integrated Global System Model-Community Atmosphere Model (IGSM-CAM) modeling framework. The core study relies on an ensemble of climate simulations under two emissions scenarios: a...

Modelling the impacts of European emission and climate change scenarios on acid-sensitive catchments in Finland

Directory of Open Access Journals (Sweden)

M. Posch

2008-03-01

Full Text Available The dynamic hydro-chemical Model of Acidification of Groundwater in Catchments (MAGIC was used to predict the response of 163 Finnish lake catchments to future acidic deposition and climatic change scenarios. Future deposition was assumed to follow current European emission reduction policies and a scenario based on maximum (technologically feasible reductions (MFR. Future climate (temperature and precipitation was derived from the HadAM3 and ECHAM4/OPYC3 general circulation models under two global scenarios of the Intergovernmental Panel on Climate Change (IPCC: A2 and B2. The combinations resulting in the widest range of future changes were used for simulations, i.e., the A2 scenario results from ECHAM4/OPYC3 (highest predicted change and B2 results from HadAM3 (lowest predicted change. Future scenarios for catchment runoff were obtained from the Finnish watershed simulation and forecasting system. The potential influence of future changes in surface water organic carbon concentrations was also explored using simple empirical relationships based on temperature and sulphate deposition. Surprisingly, current emission reduction policies hardly show any future recovery; however, significant chemical recovery of soil and surface water from acidification was predicted under the MFR emission scenario. The direct influence of climate change (temperate and precipitation on recovery was negligible, as runoff hardly changed; greater precipitation is offset by increased evapotranspiration due to higher temperatures. However, two exploratory empirical DOC models indicated that changes in sulphur deposition or temperature could have a confounding influence on the recovery of surface waters from acidification, and that the corresponding increases in DOC concentrations may offset the recovery in pH due to reductions in acidifying depositions.

Landscape fires dominate terrestrial natural aerosol - climate feedbacks

Science.gov (United States)

Scott, C.; Arnold, S.; Monks, S. A.; Asmi, A.; Paasonen, P.; Spracklen, D. V.

2017-12-01

The terrestrial biosphere is an important source of natural aerosol including landscape fire emissions and secondary organic aerosol (SOA) formed from biogenic volatile organic compounds (BVOCs). Atmospheric aerosol alters the Earth's climate by absorbing and scattering radiation (direct radiative effect; DRE) and by perturbing the properties of clouds (aerosol indirect effect; AIE). Natural aerosol sources are strongly controlled by, and can influence, climate; giving rise to potential natural aerosol-climate feedbacks. Earth System Models (ESMs) include a description of some of these natural aerosol-climate feedbacks, predicting substantial changes in natural aerosol over the coming century with associated radiative perturbations. Despite this, the sensitivity of natural aerosols simulated by ESMs to changes in climate or emissions has not been robustly tested against observations. Here we combine long-term observations of aerosol number and a global aerosol microphysics model to assess terrestrial natural aerosol-climate feedbacks. We find a strong positive relationship between the summertime anomaly in observed concentration of particles greater than 100 nm diameter and the anomaly in local air temperature. This relationship is reproduced by the model and driven by variability in dynamics and meteorology, as well as natural sources of aerosol. We use an offline radiative transfer model to determine radiative effects due to changes in two natural aerosol sources: landscape fire and biogenic SOA. We find that interannual variability in the simulated global natural aerosol radiative effect (RE) is negatively related to the global temperature anomaly. The magnitude of global aerosol-climate feedback (sum of DRE and AIE) is estimated to be -0.15 Wm-2 K-1 for landscape fire aerosol and -0.06 Wm-2 K-1 for biogenic SOA. These feedbacks are comparable in magnitude, but opposite in sign to the snow albedo feedback, highlighting the need for natural aerosol feedbacks to

Enhancement of VUV emission from a coaxial xenon excimer ultraviolet lamp driven by distorted bipolar square voltages

Energy Technology Data Exchange (ETDEWEB)

Jou, S.Y.; Hung, C.T.; Chiu, Y.M.; Wu, J.S. [Department of Mechanical Engineering, National Chiao Tung University, Hsinchu (China); Wei, B.Y. [High-Efficiency Gas Discharge Lamps Group, Material and Chemical Research Laboratories, Hsinchu (China)

2011-12-15

Enhancement of vacuum UV emission (172 nm VUV) from a coaxial xenon excimer UV lamp (EUV) driven by distorted 50 kHz bipolar square voltages, as compared to that by sinusoidal voltages, is investigated numerically in this paper. A self-consistent radial one-dimensional fluid model, taking into consideration non-local electron energy balance, is employed to simulate the discharge physics and chemistry. The discharge is divided into two three-period portions; these include: the pre-discharge, the discharge (most intense at 172 nm VUV emission) and the post-discharge periods. The results show that the efficiency of VUV emission using the distorted bipolar square voltages is much greater than when using sinusoidal voltages; this is attributed to two major mechanisms. The first is the much larger rate of change of the voltage in bipolar square voltages, in which only the electrons can efficiently absorb the power in a very short period of time. Energetic electrons then generate a higher concentration of metastable (and also excited dimer) xenon that is distributed more uniformly across the gap, for a longer period of time during the discharge process. The second is the comparably smaller amount of ''wasted'' power deposition by Xe{sup +}{sub 2} in the post-discharge period, as driven by distorted bipolar square voltages, because of the nearly vanishing gap voltage caused by the shielding effect resulting from accumulated charges on both dielectric surfaces (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Industrial strategies for improving energy efficiency and reducing greenhouse gas emissions: Examples from the Climate Wise program

International Nuclear Information System (INIS)

Buhsmer, K.; Nelson, H.; Wayman, A.; Winkelman, S.; Milmoe, P.H.

1997-01-01

Climate Wise is a partnership initiative between the US Environmental Protection Agency (EPA), the US Department of Energy (DOE), and industry designed to stimulate the voluntary reduction of greenhouse gas emissions among participating manufacturing companies. Climate Wise works with the manufacturing sector, which comprises 25 to 30 percent of the total US energy consumption, to promote the continued and increased implementation of energy efficiency and other pollution prevention measures. This paper reviews the energy use and CO 2 emissions profiles of the following three energy intensive industries: cement, petroleum, and iron and steel. The paper also identifies what a typical Action Plan for a company from each of these industries might look like and the types of savings (energy, CO 2 emissions, and energy costs) which might be achieved. The measures featured in these Action Plans are widely applicable and are likely to offer relatively short payback times. In addition, the paper describes other measures and existing or emerging technologies that may be available to these industries

Operation of Marine Diesel Engines on Biogenic Fuels: Modification of Emissions and Resulting Climate Effects

OpenAIRE

Petzold, A.; Lauer, P.; Fritsche, U.; Hasselbach, J.; Lichtenstern, M.; Schlager, H.; Fleischer, F.

2011-01-01

The modification of emissions of climate-sensitive exhaust compounds such as CO2, NOx, hydrocarbons, and particulate matter from medium-speed marine diesel engines was studied for a set of fossil and biogenic fuels. Applied fossil fuels were the reference heavy fuel oil (HFO) and the low-sulfur marine gas oil (MGO); biogenic fuels were palm oil, soybean oil, sunflower oil, and animal fat. Greenhouse gas (GHG) emissions related to the production of biogenic fuels were treated by means of a fue...

Climate forcings and climate sensitivities diagnosed from atmospheric global circulation models

Energy Technology Data Exchange (ETDEWEB)

Anderson, Bruce T. [Boston University, Department of Geography and Environment, Boston, MA (United States); Knight, Jeff R.; Ringer, Mark A. [Met Office Hadley Centre, Exeter (United Kingdom); Deser, Clara; Phillips, Adam S. [National Center for Atmospheric Research, Boulder, CO (United States); Yoon, Jin-Ho [University of Maryland, Cooperative Institute for Climate and Satellites, Earth System Science Interdisciplinary Center, College Park, MD (United States); Cherchi, Annalisa [Centro Euro-Mediterraneo per i Cambiamenti Climatici, and Istituto Nazionale di Geofisica e Vulcanologia, Bologna (Italy)

2010-12-15

Understanding the historical and future response of the global climate system to anthropogenic emissions of radiatively active atmospheric constituents has become a timely and compelling concern. At present, however, there are uncertainties in: the total radiative forcing associated with changes in the chemical composition of the atmosphere; the effective forcing applied to the climate system resulting from a (temporary) reduction via ocean-heat uptake; and the strength of the climate feedbacks that subsequently modify this forcing. Here a set of analyses derived from atmospheric general circulation model simulations are used to estimate the effective and total radiative forcing of the observed climate system due to anthropogenic emissions over the last 50 years of the twentieth century. They are also used to estimate the sensitivity of the observed climate system to these emissions, as well as the expected change in global surface temperatures once the climate system returns to radiative equilibrium. Results indicate that estimates of the effective radiative forcing and total radiative forcing associated with historical anthropogenic emissions differ across models. In addition estimates of the historical sensitivity of the climate to these emissions differ across models. However, results suggest that the variations in climate sensitivity and total climate forcing are not independent, and that the two vary inversely with respect to one another. As such, expected equilibrium temperature changes, which are given by the product of the total radiative forcing and the climate sensitivity, are relatively constant between models, particularly in comparison to results in which the total radiative forcing is assumed constant. Implications of these results for projected future climate forcings and subsequent responses are also discussed. (orig.)

Wildland fire emissions, carbon, and climate: Wildfire–climate interactions