Trends In SO2 Emissions Research Articles

Global Sulfur Dioxide Emissions and the Driving Forces.

The presence of sulfur dioxide (SO2) in the air is a global concern because of its severe environmental and public health impacts. Recent evidence from satellite observations shows rapid changes in the spatial distribution of global SO2 emissions, but such features are generally missing in global emission inventories that use a bottom-up method due to the lack of up-to-date information, especially in developing countries. Here, we rely on the latest data available on emission activities, control measures, and emission factors to estimate global SO2 emissions for the period 1960-2014 on a 0.1° × 0.1° spatial resolution. We design two counterfactual scenarios to isolate the contributions of emission activity growth and control measure deployment on historical SO2 emission changes. We find that activity growth has been the major factor driving global SO2 emission changes overall, but control measure deployment is playing an increasingly important role. With effective control measures deployed in developed countries, the predominant emission contributor has shifted from developed countries in the early 1960s (61%) to developing countries at present (83%). Developing countries show divergency in mitigation strategies and thus in SO2 emission trends. Stringent controls in China are driving the recent decline in global emissions. A further reduction in SO2 emissions would come from a large number of developing nations that currently lack effective SO2 emission controls.

Linking improvements in sulfur dioxide emissions to decreasing sulfate wet deposition by combining satellite and surface observations with trajectory analysis

Sulfur dioxide (SO2), a criteria pollutant, and sulfate (SO42−) deposition are major environmental concerns in the eastern U.S. and both have been on the decline for two decades. In this study, we use satellite column SO2 data from the Ozone Monitoring Instrument (OMI), and SO42− wet deposition data from the NADP (National Atmospheric Deposition Program) to investigate the temporal and spatial relationship between trends in SO2 emissions and the downward sulfate wet deposition over the eastern U.S. from 2005 to 2015. To establish the relationship between SO2 emission sources and receptor sites, we conducted a Potential Source Contribution Function (PSCF) analysis using HYSPLIT back trajectories for five selected Air Quality System (AQS) sites - (Hackney, OH, Akron, OH, South Fayette, PA, Wilmington, DE, and Beltsville, MD) - in close proximity to NADP sites with large downward SO42− trends since 2005. Back trajectories were run for three summers (JJA) and three winters (DJF) and used to generate seasonal climatology PSCFs for each site. The OMI SO2 and interpolated NADP sulfate deposition trends were normalized and overlapped with the PSCF, to identify the areas that had the highest contribution to the observed drop. The results suggest that emission reductions along the Ohio River Valley have led to decreases in sulfate deposition in eastern OH and western PA (Hackney, Akron and South Fayette). Farther to the east, emission reductions in southeast PA resulted in improvements in sulfate deposition at Wilmington, DE, while for Beltsville, reductions in both the Ohio River Valley and nearby favorably impacted sulfate deposition. For Beltsville, sources closer than 300 km from the site contribute roughly 56% observed deposition trends in winter, and 82% in summer, reflecting seasonal changes in transport pattern as well as faster oxidation and washout of sulfur in summer. This suggests that emissions and wet deposition are linked through not only the location of sources relative to the observing sites, but also to photochemistry and the weather patterns characteristic to the region, as evidenced by a west to east shift in the contribution between winter and summer. The method developed here is applicable to other regions with significant trends such as China and India, and can be used to estimate the potential benefits of emission reduction in those areas.

Climate-sensitive radial increment model of Norway spruce in Tyrol based on a distributed lag model with penalized splines for year-ring time series

A novel methodological framework is presented for climate-sensitive modeling of annual radial stem increment using year-ring width time series. The approach is based on a generalized additive model with penalized regression splines together with a distributed time lag model taking into account smooth nonlinear effects of a series of monthly temperature and precipitation values, as well as their interactions. Climate effects are also assumed to vary smoothly with time lag. The model framework enables both the detrending of the individual time series and the regression modeling to be performed simultaneously in a single model step. The approach is applied to year-ring width time series of Norway spruce (Picea abies (L.) H. Karst.) trees in Tyrol, Austria. The marginal response curves show that tree growth is mainly promoted by high temperatures in late spring and early summer and by precipitation in fall and winter. Summer drought does not have a negative influence on the current year’s radial increment; however, when it is associated with high temperatures, it lowers the increment in the subsequent growth period. Higher winter precipitation in conjunction with lower temperatures has a positive effect. A significant non-climate related long-term growth trend is demonstrated, probably reflecting NOx and SO2 emission trends in Austria.

Monitoring SO2emission trends and residents\u2019 perceived health risks from PGM smelting at Selous Metallurgical Complex in Zimbabwe

BackgroundPersistently high sulphur dioxide (SO2) emissions from platinum group metal (PGM) smelting pose a major threat to communities located around smelters. This paper examined SO2 emission trends, emission regulations and residents’ perceived health risks from exposures to such emissions at Selous Metallurgical Complex (SMC) PGM smelting facility in Zimbabwe.MethodsSO2 data from roof monitoring sites at the smelter furnace were aggregated into annual, quarterly and monthly emission trends from 2008 to 2015. The regulatory regime’s ability to protect human health from SO2 pollution in communities located around the smelter was examined. Questionnaire responses to perceived health risks from SO2exposure from 40 purposively sampled residents were assessed. The relationships between SO2 emission trends and residents’ self-reported health risks from exposure to SO2emissions were explored using STATA version 11. Descriptive statistics were used to illustrate SO2 emission trends and residents’ self-reported health risks from exposure to SO2.ResultsBetween 2008 and 2015, annual SO2emissions increased from 7951 to 2500 tonnes. Emissions exceeded the recommended standard limit of 50 mg/Nm3, presenting considerable adverse health risks to local residents. Concerns relating to inefficient environmental impact assessment (EIA) licensing system, poor monitoring and auditing by the environmental management agency, as well as non-deterring SO2emission exceedance penalties were identified as major drivers of emission increase. Thirty-two (80%) of the forty respondents perceived exposure to SO2 emissions as adverse and the cause of their illnesses, with coughing, nasal congestion and shortness of breath the most frequently self-reported symptoms.ConclusionA set of legally-binding SO2emission standards supported by stringent EIA licensing arrangements for smelting industries are suggested for development and enforcement to reduce the SO2emission problem. Community participation in SO2emissions monitoring is also proposed as a core part of sustainable environmental management in communities located around smelters.

A decade of global volcanic SO2 emissions measured from space

The global flux of sulfur dioxide (SO2) emitted by passive volcanic degassing is a key parameter that constrains the fluxes of other volcanic gases (including carbon dioxide, CO2) and toxic trace metals (e.g., mercury). It is also a required input for atmospheric chemistry and climate models, since it impacts the tropospheric burden of sulfate aerosol, a major climate-forcing species. Despite its significance, an inventory of passive volcanic degassing is very difficult to produce, due largely to the patchy spatial and temporal coverage of ground-based SO2 measurements. We report here the first volcanic SO2 emissions inventory derived from global, coincident satellite measurements, made by the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite in 2005–2015. The OMI measurements permit estimation of SO2 emissions from over 90 volcanoes, including new constraints on fluxes from Indonesia, Papua New Guinea, the Aleutian Islands, the Kuril Islands and Kamchatka. On average over the past decade, the volcanic SO2 sources consistently detected from space have discharged a total of ~63 kt/day SO2 during passive degassing, or ~23 ± 2 Tg/yr. We find that ~30% of the sources show significant decadal trends in SO2 emissions, with positive trends observed at multiple volcanoes in some regions including Vanuatu, southern Japan, Peru and Chile.

Diurnal temperature range over Europe between 1950 and 2005

Abstract. It has been widely accepted that diurnal temperature range (DTR) decreased on a global scale during the second half of the twentieth century. Here we show however, that the long-term trend of annual DTR has reversed from a decrease to an increase during the 1970s in Western Europe and during the 1980s in Eastern Europe. The analysis is based on the high-quality dataset of the European Climate Assessment and Dataset Project, from which we selected approximately 200 stations covering the area bordered by Iceland, Algeria, Turkey and Russia for the period 1950 to 2005. We investigate national and regional annual means as well as the pan-European mean with respect to trends and reversal periods. 17 of the 24 investigated regions including the pan-European mean show a statistical significant increase of DTR since 1990 at the latest. Of the remaining 7 regions, two show a non-significant increase, three a significant decrease and two no significant trend. Changes in DTR are affected by both surface shortwave and longwave radiation, the former of which has undergone a change from dimming to brightening in the period considered. Consequently, we discuss the connections between DTR, shortwave radiation and sulfur emissions which are thought to be amongst the most important factors influencing the incoming solar radiation through the primary and secondary aerosol effect. We find reasonable agreement between trends in SO2 emissions, radiation and DTR in areas affected by high pollution. Consequently, we conclude that the trends in DTR could be mostly determined by changes in emissions and the associated changes in incoming solar radiation.

Trends in Chemical Composition of Wet-only Precipitation at Rural French Monitoring Stations Over the 1990–2003 Period

The long-term monitoring of precipitation and its chemical composition are important for identifying trends in rain quality and for assessing the effectiveness of pollution control strategies. A statistical test has been used to the atmospheric concentrations measured in the French rural monitoring network (MERA) in order to bring out spatio-temporal trends in precipitation quality in France over the period 1990–2003. The non-parametric Mann–Kendall test which has been developed for detecting and estimating monotonic trends in the time series was used and applied in our study at annual values of wet-only precipitation concentrations. The emission data suggest that SO2 and NO x emissions decreased (−3.3 and −2.0% year−1, respectively) contrary to NH3 emissions that increased slightly (+0.2% year−1) over the period 1990–2002 in France. On the national scale, the pH values have a significant decreasing trend of −0.025 ± 0.02 unit pH year−1. % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX % garmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy0Hgip5wz % aebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY-Hhbbf9v8qqaq % Fr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qq % Q8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeWaeaaakeaaca % qGtbGaae4tamaaDaaaleaacaaI0aaabaGaaGOmaiabgkHiTaaaaaa!3BCC! $$ {\text{SO}}^{{2 - }}_{4} $$ and % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX % garmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy0Hgip5wz % aebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY-Hhbbf9v8qqaq % Fr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qq % Q8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeWaeaaakeaaca % qGUbGaae4CaiaabohacqGHsislcaqGtbGaae4tamaaDaaaleaacaaI % 0aaabaGaaGOmaiabgkHiTaaaaaa!3F96! $$ {\text{nss}} - {\text{SO}}^{{2 - }}_{4} $$ concentrations in precipitation have a significant decreasing trend, −3.0 ± 1.6 and −3.3 ± 0.6% year−1, respectively, corresponding with the downward trends in SO2 emissions in France (−3.3% year−1). A good correlation (R 2 = 0.84) between SO2 emissions and % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX % garmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy0Hgip5wz % aebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY-Hhbbf9v8qqaq % Fr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qq % Q8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeWaeaaakeaaca % qGUbGaae4CaiaabohacqGHsislcaqGtbGaae4tamaaDaaaleaacaaI % 0aaabaGaaGOmaiabgkHiTaaaaaa!3F96! $$ {\text{nss}} - {\text{SO}}^{{2 - }}_{4} $$ concentrations was obtained. The decreasing trend of % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX % garmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy0Hgip5wz % aebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY-Hhbbf9v8qqaq % Fr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qq % Q8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeWaeaaakeaaca % qGobGaaeisamaaDaaaleaacaaI0aaabaGaey4kaScaaaaa!3AF9! $$ {\text{NH}}^{ + }_{4} $$ was more significant (−5.4 ± 5.2% year−1) than that of % MathType!Translator!2!1!AMS LaTeX.tdl!TeX -- AMS-LaTeX! % MathType!MTEF!2!1!+- % feaaeaart1ev0aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX % garmWu51MyVXgatuuDJXwAK1uy0HwmaeHbfv3ySLgzG0uy0Hgip5wz % aebbnrfifHhDYfgasaacH8qrps0lbbf9q8WrFfeuY-Hhbbf9v8qqaq % Fr0xc9pk0xbba9q8WqFfea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qq % Q8frFve9Fve9Ff0dmeaabaqaciGacaGaaeqabaWaaeWaeaaakeaaca % qGobGaae4tamaaDaaaleaacaaIZaaabaGaeyOeI0caaaaa!3B0A! $$ {\text{NO}}^{ - }_{3} $$ (−1.3 ± 2.4% year−1). Globally, the concentration of the major ions showed a clear downward trend including marine and alkaline ions. In addition, the relative contribution of HNO3 to acidity precipitation increased by 51% over the studied period.

Comparison of Fine Particles and the Relationship between Particle Variations and Meteorology at an Urban Site and a Remote Site in the Eastern United States

This study compared the variations in the mass of certain particles at an urban site, Washington, DC, and at a remote site, Shenandoah National Park, VA, in the eastern United States. Seven years (1991-1997) of Interagency Monitoring of Protected Visual Environments (IMPROVE) fine particulate matter (PM2.5), PM10, coarse fraction, SO4 2−, and total sulfur data were used for this study together with available meteorology/climatology data. Various statistical modeling and analysis procedures, including time series analysis, factor analysis, and regression modeling, were employed. Time series of the constituents were divided into four terms: the long-term mean, the intra-annual perturbation, the interannual perturbation, and the synoptic perturbation. PM2.5 at the two sites made up ~72% of the total mass for PM10, and the coarse fraction made up the remaining 28%, on average. Thirty-one percent of the PM2.5 at the DC site and 42% at the Shenandoah site was SO4 2−, based on average data for the entire period. At the DC site, the two main contributors to the constituent mass were the long-term mean and the synoptic perturbation terms, and at the Shenandoah site, they were the long-term mean and the intra-annual perturbation terms. This suggested that the constituent mass at the two sites was affected by very different processes. The terms that provided the principal contribution to the constituent mass at the two sites were studied in detail. At the DC site, dew point trends, a climate variable, were the primary driver of the 7-year trends for PM2.5, PM10, the coarse fraction, and total sulfur, and SO2 emission trends were the primary driver of the trends for SO4 2−. SO2 emission trends influenced the trends for PM2.5 and total sulfur, appearing as the second term in the model, but only parameters dealing with climate trends had significant effects on the trends for PM10 and the coarse fraction. At the Shenandoah site, only parameters dealing with climate trends affected long-term particle trends.