Browsing by Subject "air pollution"

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  • Rufelt, Henry; Wiese, Björn (Suomen metsätieteellinen seura, 1981)
  • Mortensen, Lisbeth; Weisberg, Knud V. (Suomen metsätieteellinen seura, 1981)
  • Mäkelä, A.; Hari, P.; Kellomäki, Seppo (Suomen metsätieteellinen seura, 1981)
  • Forsius, Martin; Posch, Maximilian; Holmberg, Maria; Vuorenmaa, Jussi; Kleemola, Sirpa; Augustaitis, Algirdas; Beudert, Burkhard; Bochenek, Witold; Clarke, Nicholas; de Wit, Heleen A.; Dirnböck, Thomas; Frey, Jane; Grandin, Ulf; Hakola, Hannele; Kobler, Johannes; Krám, Pavel; Lindroos, Antti-Jussi; Löfgren, Stefan; Pecka, Tomasz; Rönnback, Pernilla; Skotak, Krzysztof; Szpikowski, Józef; Ukonmaanaho, Liisa; Valinia, Salar; Váňa, Milan (Elsevier, 2021)
    Science of The Total Environment 753 (2021), 141791
    Anthropogenic emissions of nitrogen (N) and sulphur (S) compounds and their long-range transport have caused widespread negative impacts on different ecosystems. Critical loads (CLs) are deposition thresholds used to describe the sensitivity of ecosystems to atmospheric deposition. The CL methodology has been a key science-based tool for assessing the environmental consequences of air pollution. We computed CLs for eutrophication and acidification using a European long-term dataset of intensively studied forested ecosystem sites (n = 17) in northern and central Europe. The sites belong to the ICP IM and eLTER networks. The link between the site-specific calculations and time-series of CL exceedances and measured site data was evaluated using long-term measurements (1990–2017) for bulk deposition, throughfall and runoff water chemistry. Novel techniques for presenting exceedances of CLs and their temporal development were also developed. Concentrations and fluxes of sulphate, total inorganic nitrogen (TIN) and acidity in deposition substantially decreased at the sites. Decreases in S deposition resulted in statistically significant decreased concentrations and fluxes of sulphate in runoff and decreasing trends of TIN in runoff were more common than increasing trends. The temporal developments of the exceedance of the CLs indicated the more effective reductions of S deposition compared to N at the sites. There was a relation between calculated exceedance of the CLs and measured runoff water concentrations and fluxes, and most sites with higher CL exceedances showed larger decreases in both TIN and H+ concentrations and fluxes. Sites with higher cumulative exceedance of eutrophication CLs (averaged over 3 and 30 years) generally showed higher TIN concentrations in runoff. The results provided evidence on the link between CL exceedances and empirical impacts, increasing confidence in the methodology used for the European-scale CL calculations. The results also confirm that emission abatement actions are having their intended effects on CL exceedances and ecosystem impacts.
  • Zaidan, Martha A.; Wraith, Darren; Boor, Brandon E.; Hussein, Tareq (2019)
    Black carbon (BC) is an important component of particulate matter (PM) in urban environments. BC is typically emitted from gas and diesel engines, coal-fired power plants, and other sources that burn fossil fuel. In contrast to PM, BC measurements are not always available on a large scale due to the operational cost and complexity of the instrumentation. Therefore, it is advantageous to develop a mathematical model for estimating the quantity of BC in the air, termed a BC proxy, to enable widening of spatial air pollution mapping. This article presents the development of BC proxies based on a Bayesian framework using measurements of PM concentrations and size distributions from 10 to 10,000 nm from a recent mobile air pollution study across several areas of Jordan. Bayesian methods using informative priors can naturally prevent over-fitting in the modelling process and the methods generate a confidence interval around the prediction, thus the estimated BC concentration can be directly quantified and assessed. In particular, two types of models are developed based on their transparency and interpretability, referred to as white-box and black-box models. The proposed methods are tested on extensive data sets obtained from the measurement campaign in Jordan. In this study, black-box models perform slightly better due to their model complexity. Nevertheless, the results demonstrate that the performance of both models does not differ significantly. In practice, white-box models are relatively more convenient to be deployed, the methods are well understood by scientists, and the models can be used to better understand key relationships.
  • Cape, J. N.; Fowler, D. (Suomen metsätieteellinen seura, 1981)
  • Molski, Boguslaw; Bytnerowicz, Andrzej; Dmuchowski, Wojciech (Suomen metsätieteellinen seura, 1981)
  • Wang, Yonghong; Gao, Wenkang; Wang, Shuai; Song, Tao; Gong, Zhengyu; Ji, Dongsheng; Wang, Lili; Liu, Zirui; Tang, Guiqian; Huo, Yanfeng; Tian, Shili; Li, Jiayun; Li, Mingge; Yang, Yuan; Chu, Biwu; Petäjä, Tuukka; Kerminen, Veli-Matti; He, Hong; Hao, Jiming; Kulmala, Markku; Wang, Yuesi; Zhang, Yuanhang (2020)
    Although much attention has been paid to investigating and controlling air pollution in China, the trends of air-pollutant concentrations on a national scale have remained unclear. Here, we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017, during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions. Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China, with an annual decrease of similar to 7% compared with measurements in 2013. The measured decreased concentrations of SO2, NO2 and CO (a proxy for anthropogenic volatile organic compounds) could explain a large fraction of the decreased PM2.5 concentrations in different regions. As a consequence, the heavily polluted days decreased significantly in corresponding regions. Concentrations of organic aerosol, nitrate, sulfate, ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017, connecting the decreases in aerosol precursors with corresponding chemical components closely. However, surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017, which indicates stronger photochemical pollution. The boundary-layer height in capital cities of eastern China showed no significant trends over the Beijing-Tianjin-Hebei, Yangtze River Delta and Pearl River Delta regions from 2013 to 2017, which confirmed the reduction in anthropogenic emissions. Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017, although the ozone concentration has increased significantly, suggesting a more complex mechanism of improving Chinese air quality in the future.
  • Kärenlampi, Lauri; Friedland, Andrew J. (Suomen metsätieteellinen seura, 1988)
  • Mikkonen, Hilkka; Huttunen, Satu (Suomen metsätieteellinen seura, 1981)
  • Lehtiö, Helena (Suomen metsätieteellinen seura, 1981)
  • Jokinen, Juhani; Karjalainen, Reijo; Säynätkari, Tapani; Häkkinen, Antti; Markkanen, Kari (Suomen metsätieteellinen seura, 1983)
  • Runeckles, V. C.; Palmer, K. T.; Trabelsi, H. (Suomen metsätieteellinen seura, 1981)
  • Ding, A. J.; Huang, X.; Nie, W.; Sun, J. N.; Kerminen, V. -M.; Petäjä, T.; Su, H.; Cheng, Y. F.; Yang, X. -Q.; Wang, M. H.; Chi, X. G.; Wang, J. P.; Virkkula, A.; Guo, W. D.; Yuan, J.; Wang, S. Y.; Zhang, R. J.; Wu, Y. F.; Song, Y.; Zhu, T.; Zilitinkevich, S.; Kulmala, M.; Fu, C. B. (2016)
    Aerosol-planetary boundary layer (PBL) interactions have been found to enhance air pollution in megacities in China. We show that black carbon (BC) aerosols play the key role in modifying the PBL meteorology and hence enhancing the haze pollution. With model simulations and data analysis from various field observations in December 2013, we demonstrate that BC induces heating in the PBL, particularly in the upper PBL, and the resulting decreased surface heat flux substantially depresses the development of PBL and consequently enhances the occurrences of extreme haze pollution episodes. We define this process as the dome effect of BC and suggest an urgent need for reducing BC emissions as an efficient way to mitigate the extreme haze pollution in megacities of China.
  • Bramryd, Torleif (Suomen metsätieteellinen seura, 1981)
  • Scholz, F. (Suomen metsätieteellinen seura, 1981)
  • Garcia, Leandro; Johnson, Rob; Johnson, Alex; Abbas, Ali; Goel, Rahul; Tatah, Lambed; Damsere-Derry, James; Kyere-Gyeabour, Elvis; Tainio, Marko; de Sá, Thiago H.; Woodcock, James (Pergamon, 2021)
    Environment International 155, 106680
    Background: Health impact assessments of alternative travel patterns are urgently needed to inform transport and urban planning in African cities, but none exists so far. Objective: To quantify the health impacts of changes in travel patterns in the Greater Accra Metropolitan Area, Ghana. Methods: We estimated changes to population exposures to physical activity, air pollution, and road traffic fatality risk and consequent health burden (deaths and years of life lost prematurely – YLL) in response to changes in transportation patterns. Five scenarios were defined in collaboration with international and local partners and stakeholders to reflect potential local policy actions. Results: Swapping bus and walking trips for car trips can lead to more than 400 extra deaths and 20,500 YLL per year than travel patterns observed in 2009. If part of the rise in motorisation is from motorcycles, we estimated an additional nearly 370 deaths and over 18,500 YLL per year. Mitigating the rise in motorisation by swapping long trips by car or taxi to bus trips is the most beneficial for health, averting more than 600 premature deaths and over 31,500 YLL per year. Without significant improvements in road safety, reduction of short motorised trips in favour of cycling and walking had no significant net health benefits as non-communicable diseases deaths and YLL benefits were offset by increases in road traffic deaths. In all scenarios, road traffic fatalities were the largest contributor to changes in deaths and YLL. Conclusions: Rising motorisation, particularly from motorcycles, can cause significant increase in health burden in the Greater Accra Metropolitan Area. Mitigating rising motorisation by improving public transport would benefit population health. Tackling road injury risk to ensure safe walking and cycling is a top priority. In the short term, this will save lives from injury. Longer term it will help halt the likely fall in physical activity.
  • Johnsen, Ib (Suomen metsätieteellinen seura, 1981)