The impact of air pollutant and methane emission controls on tropospheric ozone and radiative forcing: CTM calculations for the period 1990-2030

To explore the relationship between tropospheric ozone and radiative forcing with changing emissions, we compiled two sets of global scenarios for the emissions of the ozone precursors methane (CH₄), carbon monoxide (CO), non-methane volatile organic compounds (NMVOC) and nitrogen oxides (NO_x) up to the year 2030 and implemented them in two global Chemistry Transport Models. The 'Current Legislation' (CLE) scenario reflects the current perspectives of individual countries on future economic development and takes the anticipated effects of presently decided emission control legislation in the individual countries into account. In addition, we developed a 'Maximum technically Feasible Reduction' (MFR) scenario that outlines the scope for emission reductions offered by full implementation of the presently available emission control technologies, while maintaining the projected levels of anthropogenic activities. Whereas the resulting projections of methane emissions lie within the range suggested by other greenhouse gas projections, the recent pollution control legislation of many Asian countries, requiring introduction of catalytic converters for vehicles, leads to significantly lower growth in emissions of the air pollutants NO_x, NMVOC and CO than was suggested by the widely used and more pessimistic IPCC (Intergovernmental Panel on Climate Change) SRES (Special Report on Emission Scenarios) scenarios (Nakicenovic et al., 2000), which made Business-as-Usual assumptions regarding emission control technology. With the TM3 and STOCHEM models we performed several long-term integrations (1990-2030) to assess global, hemispheric and regional changes in CH₄, CO, hydroxyl radicals, ozone and the radiative climate forcings resulting from these two emission scenarios. Both models reproduce broadly the observed trends in CO, and CH₄ concentrations from 1990 to 2002. <P style='line-height: 20px;'> For the 'current legislation' case, both models indicate an increase of the annual average ozone levels in the Northern Hemisphere by 5ppbv, and up to 15ppbv over the Indian sub-continent, comparing the 2020s (2020-2030) with the 1990s (1990-2000). The corresponding higher ozone and methane burdens in the atmosphere increase radiative forcing by approximately 0.2 Wm^-2. Full application of today's emissions control technologies, however, would bring down ozone below the levels experienced in the 1990s and would reduce the radiative forcing of ozone and methane to approximately -0.1 Wm^-2. This can be compared to the 0.14-0.47 Wm^-2 increase of methane and ozone radiative forcings associated with the SRES scenarios. While methane reductions lead to lower ozone burdens and to less radiative forcing, further reductions of the air pollutants NO_x and NMVOC result in lower ozone, but at the same time increase the lifetime of methane. Control of methane emissions appears an efficient option to reduce tropospheric ozone as well as radiative forcing

Gap solitons in spatiotemporal photonic crystals

We generalize the concept of nonlinear periodic structures to systems that show arbitrary spacetime variations of the refractive index. Nonlinear pulse propagation through these spatiotemporal photonic crystals can be described, for shallow nonstationary gratings, by coupled mode equations which are a generalization of the traditional equations used for stationary photonic crystals. Novel gap soliton solutions are found by solving a modified massive Thirring model. They represent the missing link between the gap solitons in static photonic crystals and resonance solitons found in dynamic gratings.Comment: 3 figures, submitte

GAINS: The impact of economic crisis on GHG mitigation potentials and costs in Annex I Countries

This report analyzes how GHG mitigation potentials and costs in the Annex I countries of the UNFCCC are influenced by the current economic crisis

Positive solutions to indefinite Neumann problems when the weight has positive average

We deal with positive solutions for the Neumann boundary value problem associated with the scalar second order ODE $$u" + q(t)g(u) = 0, \quad t \in [0, T],$$ where $g: [0, +\infty[\, \to \mathbb{R}$ is positive on $\,]0, +\infty[\,$ and $q(t)$ is an indefinite weight. Complementary to previous investigations in the case $\int_0^T q(t) < 0$, we provide existence results for a suitable class of weights having (small) positive mean, when $g'(x) < 0$ at infinity. Our proof relies on a shooting argument for a suitable equivalent planar system of the type $$x' = y, \qquad y' = h(x)y^2 + q(t),$$ with $h(x)$ a continuous function defined on the whole real line.Comment: 17 pages, 3 figure

Compliance with EU air quality limit values - A first set of sensitivity and optimization analyses

This report provides additional information to the baseline and optimized scenarios that have been developed for the review and revision of the Thematic Strategy on Air Pollution in TSAP Reports #6 and #7. The report examines the implications of different assumptions on the implementation of the Euro-6 emission standards for light duty diesel vehicles on compliance with NO2 air quality limit values in Europe. For the baseline assumptions of the TSAP-2012 baseline scenario, i.e., a decline of real-driving emission in two stages down to 1.5 times the value of test cycle value in 2018, it is estimated that almost all AIRBASE stations that have been modelled in this exercise would achieve the NO2 limit values by 2030 at the latest. However, in the least optimistic sensitivity case, i.e., under the assumption of a failure of Euro-6 (no change in real-driving emissions compared to Euro-4), about 100 out of the 1173 AIRBASE monitoring stations would still remain in non-compliance with the limit value in 2030. A second analysis examines the optimization results presented in TSAP Report #7 in more detail and provides, for each of the optimized scenarios, the sectors in which emission reductions would occur in the cost-optimal cases. These emission reductions will lead to lower background pollution concentrations in Europe, which will affect PM10 levels within cities. It is estimated, e.g., for the high ambition case, that in 2030 the number of stations for which non-compliance is robustly estimated will decline by about 20%. The number of stations for which compliance seems possible but not certain would fall by 30% compared to the baseline. In contrast, the optimized scenarios do not yield significant improvements in the compliance with NO2 limit values, as the series of scenarios did not consider further measures for road vehicle emissions. Finally, an initial assessment of current and future emissions of mercury in Europe suggests for the TSAP-2012 baseline a decline of Hg emissions of 22% in 2020 and about 30% in 2030 (relative to 2005), mainly as a consequence of lower coal use in the power sector. Full implementation of the available technical emission controls, especially of certain measures to reduce PM emissions, could eliminate Hg emissions in the EU by another third, so that in 2030 the total release of Hg in the EU could be more than 50% lower than in 2005

Emission of Air Pollutants in the Region of the Central European Initiative - 1988

This paper presents an emission inventory of sulfur dioxide (SO2), nitrogen oxides (NO,), particulate matter (PM) and carbon dioxide (CO2), for the countries cooperating in the Central European Initiative, i.e., Austria, Croatia, Czechoslovakia, Hungary, Italy, Poland, Slovenia. The inventory is based on national and regional statistics as well as on information available from the collaborating institutions, which has not yet been internationally published. National data has been verified and converted into a common format, consistent with the database used by the European Environmental Agency and the European Community (the CORINAIR system). The inventory describes emissions in the year 1988 (before the restructuring process began in former socialist economies). Data has been collected for three levels: National, Administrative, Large Point Sources (LPS). A point source database has been created, in which specific information (e.g., capacity, commissioning year, fuel use, production) about 400 large plants in Central Europe is stored. The result of this work represents the first consistent inventory of the sources of air pollution in Central Europe

Modeling Particulate Emissions in Europe. A Framework to Estimate Reduction Potential and Control Costs

This paper presents the extension of the Regional Air Pollution Information and Simulation (RAINS) model that addresses present and future emissions of fine particulates in Europe, the potential for controlling these emissions and the costs of such emission reductions. Together with the existing modules dealing with the emissions of the precursor emissions of secondary aerosols such as sulphur dioxide (SO2), nitrogen oxides (NOx), ammonia (NH3) and volatile organic compounds (VOC), this extension enables the comparison of the potentials and costs for controlling primary emissions of fine particles with those of secondary aerosols and to find cost-minimal approaches for reducing ambient levels of particulate matter. The emissions of particulate matter (PM) in the RAINS model are calculated for three different size classes: the fine fraction (PM2.5), the coarse fraction (PM10 - PM2.5) and large particles (PM_>10 5m). Summed up, these three fractions represent total suspended particles (TSP). Fine particles are emitted from a large number of sources with large differences in their technical and economic properties. The methodology distinguishes 392 source categories for stationary energy combustion, industrial processes, mobile sources and agriculture. For each of these sectors, the study explores the applicable options for reducing PM emissions, their efficiency and their costs. Emissions characteristics of the individual sectors are strongly determined by country-specific conditions. The methodology estimates emission control costs of standard technologies under the specific conditions characteristic for the various European countries. Based on the assumption of the general availability of control technologies with equal technical properties and costs, a number of country-specific circumstances (level of technological advancement, installation size distribution, labor costs, etc.) are used to estimate the costs for the actual operation of pollution control equipment. For the individual source sectors, emissions are estimated based on statistical information on economic activity and emission factors that reflect hypothetical emissions if no control measures were applied. These emission factors were taken from the literature and were, to the maximum possible extent, adapted to the country-specific conditions. Actual emissions are calculated taking into account the application of emission control measures in a given sector, for which also costs are estimated. The methodology was implemented for all European countries, covering the period from 1990 to 2010. At an aggregated level, estimates for past years (1990, 1995) correspond well with other national and international inventories. However, discrepancies are found for some detailed results for individual sectors and activities, and more work will be necessary to clarify them. This preliminary implementation suggests for Europe a 50 percent decline of primary emissions of fine particles between 1990 and 1995, mainly due to the economic restructuring in central and eastern European countries. The recently tightened regulations on large combustion plants and mobile sources will further reduce PM emissions, so that for 2010 European PM emissions are expected to be 60 percent below the level of 1990. However, less improvement is expected for the health-relevant fraction of fine particles (PM2.5). It needs to be emphasized that these preliminary estimates are still associated with considerable uncertainties, and more work, involving national experts, will be necessary to obtain a verified and generally accepted European data base to estimate the potential for further reductions of fine particles in Europe. The present implementation (version 2.00) of the RAINS PM module on the Internet (www.iiasa.ac.at/rains/Rains-online.html) provides free access to the input data and results to facilitate interaction with national experts

Adiabatic Approximation for weakly open systems

We generalize the adiabatic approximation to the case of open quantum systems, in the joint limit of slow change and weak open system disturbances. We show that the approximation is ``physically reasonable'' as under wide conditions it leads to a completely positive evolution, if the original master equation can be written on a time-dependent Lindblad form. We demonstrate the approximation for a non-Abelian holonomic implementation of the Hadamard gate, disturbed by a decoherence process. We compare the resulting approximate evolution with numerical simulations of the exact equation.Comment: New material added, references added and updated, journal reference adde