Source Categories Research Articles

Uncertainties in the Emissions Database for Global Atmospheric Research (EDGAR) emission inventory of greenhouse gases

Abstract. The Emissions Database for Global Atmospheric Research (EDGAR) estimates the human-induced emission rates on Earth. EDGAR collaborates with atmospheric modelling activities and aids policy in the design of mitigation strategies and in evaluating their effectiveness. In these applications, the uncertainty estimate is an essential component, as it quantifies the accuracy and qualifies the level of confidence in the emission. This study complements the EDGAR emissions inventory by providing an estimation of the structural uncertainty stemming from its base components (activity data, AD, statistics and emission factors, EFs) by (i) associating uncertainty to each AD and EF characterizing the emissions of the three main greenhouse gases (GHGs), namely carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O); (ii) combining them; and (iii) making assumptions regarding the cross-country uncertainty aggregation of source categories. It was deemed a natural choice to obtain the uncertainties in EFs and AD statistics from the Intergovernmental Panel on Climate Change (IPCC) guidelines issued in 2006 (with a few exceptions), as the EF and AD sources and methodological aspects used by EDGAR have been built over the years based on the IPCC recommendations, which assured consistency in time and comparability across countries. On the one hand, the homogeneity of the method is one of the key strengths of EDGAR, on the other hand, it facilitates the propagation of uncertainties when similar emission sources are aggregated. For this reason, this study aims primarily at addressing the aggregation of uncertainties' sectorial emissions across GHGs and countries. Globally, we find that the anthropogenic emissions covered by EDGAR for the combined three main GHGs for the year 2015 are accurate within an interval of −15 % to +20 % (defining the 95 % confidence of a log-normal distribution). The most uncertain emissions are those related to N2O from waste and agriculture, while CO2 emissions, although responsible for 74 % of the total GHG emissions, account for approximately 11 % of global uncertainty share. The sensitivity to methodological choices is also discussed.

I Resent that I Have Helped you! A Qualitative Study of Sources and Consequences of Resentment of Helping

Drawing upon conservation of resources (COR) theory, prior research has shown how helping behavior leads to a depleted condition experienced by the helper. It, however, remains ambiguous regarding why some helping situations allow the helper to have positive experiences while other situations lead to depleted experiences? Utilizing the grounded theory approach with inductive reasoning, we find two broad categories of sources leading to resentment of helping, including characteristics of the recipient and performance-related threats. Moreover, we propose that when resentment of helping is experienced, helping discontinuation is likely to occur. Furthermore, we theorize that forgiveness and organizational rewards moderate the relationship between resentment of helping and helping discontinuation. Theoretical and managerial implications are also discussed.

The classification of education in surveys: a generalized framework for ex-post harmonization

All social science (and many other) surveys measure respondents’ educational attainment. However, most of them do it in different ways, resulting in incoherent education variables across surveys. This complicates the cumulation of different datasets and hampers survey data reuse. For cross-national surveys that are designed to be comparative from the outset, methods for ensuring comparability in the measurement of education across countries have improved substantially over the last decades, relying on ex-ante output harmonization. For ex-post harmonization, the situation is more difficult because the data have already been collected, with education measures that only partly overlap in the amount and kind of information they store about respondents’ education. This results in aggregated measures when harmonizing data ex-post. Such aggregated measures may underestimate associations with education in multivariate analyses, leading to biased results. They also do not allow testing hypotheses on the effects of specific types of education, such as vocational programs. This paper presents a new framework for harmonizing education variables ex-post, building on the International Standard Classification of Education (ISCED) and experience from cross-national surveys using ex-ante harmonization. It includes a new coding scheme called ‘generalized ISCED’ or GISCED, and extension variables standardizing aspects of education not covered by ISCED. It proposes solutions for problems that specifically occur in ex-post harmonization, for example source categories spanning ISCED levels. The paper also shows how to apply the GISCED framework to existing data. An empirical illustration shows how detailed harmonized education measures may give insights for research and policy not possible with more aggregate measures.

Aspects of Translating Musical Instruments in Foreign Travellers Through the Romanian Principalities, I-X Series of Volumes

Abstract Whether we are talking about those written directly in Romanian, or whether we are referring to those translated into the same language, the narrative sources are the main source of documentation in the process of reconstructing any aspect related to our past. Regarding music and all the elements related to it, the category of sources we refer to is the most important source of information, even if, in relation to other aspects, music is relatively little “present” within these writings. Therefore, trying to correctly and accurately determine the described musical instruments, as well as the related terminology, is important, but also difficult. On the occasion of a more extensive work (i.e. doctoral thesis) I noticed, especially in the category of sources referred to here, a series of mistranslated musical instruments which makes it difficult or even far from understanding and creating a more accurate picture of the musical atmosphere of past centuries. All these aspects draw our attention first of all by resorting to comparing the translations with the original version after which they were made, but also by comparing the descriptions regarding music related to Romania with those referring to Romaniansʼ neighbors or those with which we have come into consistent contact with throughout history. Therefore, in the following, we propose to analyze the main cases of mistranslations identified by us, a comparison with the original alternatives of the texts after which they were made, but also a framing of the historical context, without which the proper understanding risks would not be fully achieved.

Digital Reading and the Concept of Ebook: Metaphorical Analysis of Preservice Teachers’ Perceptions Regarding the Concept of Ebook

The aim of this study was to determine the metaphorical perceptions of preservice Turkish teachers (PTTs) regarding the concept of ebook. In accordance with this aim, answers to the questions of “What are the metaphors used by PTTs for the concept of e-book?” and “Under which categories could the metaphors used by PTTs for the concept of e-book be collected?” were sought. A total of 150 preservice teachers studying in the Faculty of Education, Turkish Education Department at Çukurova University, constituted the participants of the research designed according to the phenomenology design, one of the qualitative research methods. A semi-structured interview form was used as data collection tool. Data were analyzed using the content analysis technique. As a result of the study, it was determined that eight categories emerged from the metaphors produced by PTTs for ebook and that they mostly had positive meanings. These categories are, namely, facilitating, information source, accessible, portable, requirement, inadequate, attractive, and harmful. PTTs mostly produced metaphors for ebook in the facilitating category. It was followed by the information source and accessible categories. It was determined that some PTTs produced negative metaphors for ebooks, and these negative metaphors were collected under the inadequate and harmful categories.

Organic compound source profiles of PM2.5 from traffic emissions, coal combustion, industrial processes and dust

Eighteen polycyclic aromatic hydrocarbons (PAHs), 24 n-alkanes, 7 hopanes, 2 cholestanes, inorganic ions, elements and carbon fractions were analyzed in real-world source samples of PM2.5 (fine particulate matter) from traffic emissions (gasoline vehicles-TGV, diesel vehicles-TDV, diesel ship-TDS, and heavy oil ships-THOS), coal combustion (coal-fired industrial boilers-CIB, power plants-CPP, and residential stoves-CRS), industrial process emissions (cement industry-IPCI, and steel industry-IPSI), and dust (soil dust-DSD, road dust-DRD, and construction dust-DCD). High molecular weight (sum of five to seven rings) PAHs accounted for higher fractions for TGV (80%) and THS (61%) than for TDV, TDS and coal combustion sources (31%–47%). Hopane ratios (C29αβ/C30αβ) in coal related sources were mostly higher than 1, whereas that of traffic emissions was lower than 1. The homohopane index [S/(S + R)], which is a useful index for identifying the maturity of fuels, ranked as TGV > THS > TDV and TDS > coal combustion. For n-alkane profiles, coal related sources showed peaks at C16–C19, TDV, TDS and THS showed similar peaks at C17–C25, but peaks for DSD (C30–C32), DRD (C17–C20, C24–25 and C30–C31), CRS (C16–C18 and C28–C29) and TGV (C24–C26) are different. Organic markers were selected which can best differentiate the subtypes within source categories by considering the component levels and variations. Through a comprehensive review, we showed that it is inadvisable to directly use diagnostic ratios for source attribution, although their trends can assist in identifying influential sources.

Exploring the extent of digital food and beverage related content associated with a family-friendly event: a case study

BackgroundExposure to unhealthy food and beverage content is a contributing factor to the obesity epidemic. Youth are susceptible to unhealthy digital food marketing including content shared by their peers, which can be as influential as commercial marketing. Current Canadian regulations do not consider the threat digital food marketing poses to health. No research to date has examined the prevalence of food related posts on social media surrounding family-friendly events. The aim of this study was to explore the frequency of food related content (including food marketing) and the marketing techniques employed in social media posts related to a family-friendly event in Canada.MethodsIn this case study, a content analysis of social media posts related to a family-friendly event on Facebook, Twitter, and Instagram was conducted between January to February 2019. Each post containing food related content was identified and categorized by source and food category using a coding manual. Marketing techniques found in each food related post were also assessed.ResultsA total of 732 food and beverage related posts were assessed. These posts were most commonly promoted through Instagram (n = 561, 76.6%) with significantly more individual users (61.5%; p < 0.05) generating food and beverage related content (n = 198, 27%) than other post sources. The top most featured food category was fast food (n = 328, 44.8%) followed by dine-in restaurants (n = 126, 17.2%). The most frequently observed marketing techniques included predominantly featuring a child in the post (n = 124, 16.9%; p < 0.0001), followed by products intended for children (n = 118, 16.1%; p < 0.05), and the presence of family (n = 57, 7.8%; p < 0.0001).ConclusionsThe present study highlights the proliferation of unhealthy food and beverage content by individuals at a family-friendly event as well as the presence of food marketing. Due to the unfettered advertising found in digital spaces, and that they are largely unregulated, it is important for future policies looking to combat childhood obesity to consider incorporating social media into their regulations to safeguard family-friendly events. General awareness on the implications of peer to peer sharing of unhealthy food and beverage posts should also be considered.

Atmospheric ammonia point source detection technique at regional scale using high resolution satellite imagery and deep learning

Ammonia (NH3) is a precursor of atmospheric aerosols. The lack of real-time updated and high spatial resolution atmospheric NH3 point source information is one of the critical problems in the study of atmospheric pollution. Satellite-based NH3 observation data provide a new approach to NH3 point source detection. However current spatial resolution of NH3 concentration satellite data is still not sufficient to extract NH3 point sources at regional scale with high accuracy. Based on the traditional oversampling method to improve the spatial resolution of NH3 satellite data, this paper used high-resolution satellite image data with the geometric morphological features of NH3 point sources to detect the NH3 point sources at regional scale under deep learning techniques. The high-precision NH3 point source location and category information at regional scale is extracted concurrently, solving the current problem that multiple point sources cannot be detected in a single satellite NH3 concentration hotspot. After analyzing a priori knowledge, the industrial sources were further subdivided. The atmospheric ammonia point source detection technique in this paper were used in Northeast China, where the number and types of NH3 emission sources are abundant. The detection results significantly increased the number of NH3 potential point sources detected in Northeast China compared with the traditional oversampling method. The deep learning-based technology combines NH3 concentration remote sensing products with high resolution satellite image data to effectively detect the spatial distribution and types of NH3 point sources at regional scale, providing powerful technical support for NH3 emission regulation and control.

Assessment of long-range oriented source and oxidative potential on the South-west shoreline, Korea: Molecular marker receptor models during shipborne measurements

In order to determine the quantitative contributions of PM2.5 on the South-west shoreline of Korea, filter based samplings were conducted in the summertime of 2017 and 2018 (total 32 days) via shipborne measurements using both a high volume and middle volume air sampler. Water-soluble organic carbon, water-soluble ions, organic carbon and elemental carbon, elemental species, and organic molecular markers by Liquid Chromatography–tandem Mass Spectrometry were utilized to characterize the collected substrates. The current study investigates the (1) chemical characteristics of PM2.5, (2) source apportionment using positive matrix factorization (PMF), and (3) relationship between sources and the dithiothreitol (DTT) assay during the two sampling periods. A mean PM2.5 concentration of 19.3 μg/m3 was observed along the entire sampling route. The ratio of water-soluble to organic carbon implies that secondary aerosol formation is dominant. The result of methanesulfonic acid (MSA) suggests the contribution of a marine-oriented biogenic source of PM2.5. The PMF source apportionment model showed six source categories with reasonably stable profiles: 1) sulfate-rich, 2) MSA-rich, 3) nitrate-rich, 4) secondary organic, 5) continental, and 6) biomass burning sources. The PMF showed three strong events (i.e., long-range transport, mixed (ocean and long-range stay), and domestic origin events) in the contributions of sources, as well as a dependence on wind transport. Higher associations with DTT oxidative potential normalized to PM2.5 mass concentration (DTT–OPm) related to long-range transport, hence, confirming the impacts of the highest intrinsic oxidative potential.

Integrating Chemical Mass Balance and the Community Multiscale Air Quality models for source identification and apportionment of PM2.5

Source apportionment offers an efficient way to identify emission sources and the contributions to air pollution. It helps to deepen our understanding of the air pollution formation process and develop productive environmental policies. Accurate PM2.5 source apportionment is more essential for small-scale local air pollution control. An integrated source apportionment approach was built by combining chemical mass balance (CMB) model and the Community Multiscale Air Quality modelling system (CMAQ) model to complement individual model and apportion PM2.5 pollution into more elaborate emission sources categories. The CMAQ source apportionment results of corresponding PM2.5 precursors were applied to assign secondary components while that of PM2.5 were applied to assign non-local sources as the basic constrains. An island city with typical secondary components in PM2.5 pollution was chosen. The results showed the dominant source impacts of non-local sources ranged from 31.07% in summer to 49.60% in winter. Compared to individual model, the integrated source apportionment approach preserved the accuracy of CMB modelling for primary sources, simultaneously apportioned the secondary components to the primary sources and abstracted non-local sources from primary sources, which acquired more elaborate results. The results further helped develop more efficient air quality control policies.

A theoretical framework for classifying occupant-centric data streams on indoor climate using a physiological and cognitive process hierarchy

New and pervasive information and communication technologies have made it possible to capture a large range of continuous data from, or close to, each individual building occupant. These occupant-centric data streams may include subjective votes, evaluations, complaints, control actions, physiological measurements such as heart rate or pupil size, physical measurements of skin temperature or local draft and air temperature measurements, and much more. Currently, considerable resources are put into studies that focus on the development and potential uses of such systems, while the origin and nature of the collected information which is embedded in the data is poorly investigated. In this paper, we propose a taxonomy for the classification of occupant-centric data streams, developed through the application of established theories and categories in environmental and market psychology. The proposed framework organises five data source categories and links them to four levels of physiological and cognitive processes, making an explicit connection between data and embedded information attributes. The framework, originally developed to classify continuous occupant centric data in the domain of indoor climate, can also bring insights that might help explain known gaps and challenges in different models and theories that aim at predicting individual satisfaction with indoor climate conditions.

Use of social media information sources: a systematic literature review

PurposeThis paper aimed to investigate reading format preference of undergraduate students with regard to various categories of information sources and use of social media information sources for academic and non-academic activities.Design/methodology/approachAn exhaustive literature review was carried out in a very well organised way using total 56 publications which include 48 research papers, four conference papers, two books and two reports, which were selected for analysis on the basis of prescribed data schema and adopting the inclusion and exclusion criteria matching with the research objectives of the study.FindingsUndergraduate students preferred text books in print format for passing the exams, and use of search engines and Internet sites were rated as the most crucial source for the academic information. In particular, Wikipedia, YouTube and Blogs were the most frequently used social media information sources by undergraduate students for their academic activities. However, Facebook and Twitter were most prominently used for social interaction.Research limitations/implicationsThe population of the study was restricted to the homogenous group of users, i.e. undergraduate students to examine their choices and preferences for their academic and non-academic activities. Further research studies may be conducted covering the more diverse and heterogeneous user group of postgraduate students and research scholars of different disciplines.Originality/valueGenerally, many previous research studies depicted users' preference for print and electronic media format without paying special attention on the usage of a variety of information sources by user groups. However, the present study is a value addition to the existing literature which emphasised the use of various categories of information sources, particularly by undergraduate students in print and digital format for different purposes in the digital environment. A major shift from the use of print media to digital media to social media information sources by undergraduate students for their academic and non-academic activities.

Life Cycle Assessment of Agricultural Wood Production\u2014Methodological Options: a Literature Review

In Europe, poplar and other fast-growing tree species are considered valuable resources for meeting the required wood demand of the rising bioeconomy. The agricultural technique of short rotation coppice (SRC) has gained relevance to ease the pressure of the demand for wood from forests. Previous studies have implemented the life cycle assessment (LCA) methodology to evaluate such systems’ potential environmental impacts. These studies present different outcomes, though a general pattern on the potential benefit of SRC is observed. The variation of relevant methodological options, such as goal and scope, system boundary, functional unit, reference system, data source, characterization models, and impact categories assessed can significantly affect the results. A consequence of this discrepancy is its effect on results’ interpretation, making the absolute comparison of case studies challenging and hindering the understanding of the potential impacts of SRC LCAs in support of developing a sustainable bioeconomy. Therefore, the current research attempts to understand the methodological implementation of LCA in assessing SRC value chains. Through literature research, studies are analyzed based on the four LCA phases. One of the results of this study shows how most of the articles focus on assessing the impact category related to climate change, while other environmental issues that are particularly relevant for agricultural woody biomass systems are seldomly evaluated. By discussing the state of the art of SRC LCA, this review paper attempts to suggest improvements that will allow future LCA studies to reach a more comprehensive understanding of the overall environmental impact of SRC systems.

Black carbon aerosols over source vs. background region: Atmospheric boundary layer influence, potential source regions, and model comparison

Black carbon (BC) aerosols measured simultaneously over a source (Ahmedabad, urban) and background (Gurushikhar, high-altitude) region are analysed. The influence of atmospheric boundary layer (ABL), and potential source regions for BC are examined, and compared with model, for the first time. BC mass in Ahmedabad is significantly higher (2 to 5 times) than Gurushikhar. BC mass concentrations in Ahmedabad peak during morning and evening hours when ABL is shallow and anthropogenic emissions are high. In contrast over Gurushikhar BC emissions are higher in afternoon due to a fully evolved ABL and upward transport of pollutants from the valley/foothills during winter when Gurushikhar is within ABL. During other seasons ABL is higher and diurnal variation is suppressed. BCmax over Gurushikhar is close to BCmin over Ahmedabad, which occurs during afternoon hours when ABL is fully evolved and anthropogenic sources are negligible over Ahmedabad while emissions get transported from foothills surrounding Gurushikhar. Potential source contribution function (PSCF) analysis reveals that probable source regions for BC in these two locations are distinctly different, especially, during postmonsoon and winter, long range transport from northwestern India and the Indo-Gangetic Plain (IGP) are the probable source regions (agricultural waste and biomass burning) to the BC over the high-altitude location. Regional transport of BC emitted from urban areas of Ahmedabad to high-altitude Gurushikhar is evident in premonsoon from PSCF analysis. BC mass concentrations simulated by 2 models - MERRA-2 (fine resolution) and ECHAM6 (coarse resolution) are significantly underestimated over the source region Ahmedabad though the models capture the seasonal cycle of winter high and monsoon low. The models simulate BC mass over the background region Gurushikhar well. The magnitude of BC mass concentrations simulated by both models over Ahmedabad and Gurushikar are quite similar. This observation-model comparative analysis reveals that anthropogenic aerosol emissions, especially BC and its long range transport are inadequately represented in models, in particular over the source regions strongly suggesting that improvements in emission inventories of aerosol sources as well as inclusion of missing aerosol source categories are needed. Such quantitative evaluation of BC aerosols over a source and a background region due to the influence of ABL, and potential source regions are hitherto unavailable over tropics which can be used to improve the representation of aerosols in models and thereby estimates of radiative and climate effects due to aerosols.

Global and national assessment of the incidence of asthma in children and adolescents from major sources of ambient NO2

Pediatric asthma incidence has been associated with exposure to nitrogen dioxide (NO2) in ambient air. NO2 is predominantly emitted through fossil fuel use in land transportation, power generation and the burning of solid biofuels in households. We simulated NO2 with a global atmospheric chemistry model, combined with a land use regression model, to estimate NO2 exposure in all countries worldwide. The global asthma incidence among children and adolescents attributable to NO2 was estimated by deriving an exposure-response function from a meta-analysis which included epidemiological studies from multiple countries, baseline incidence rates from the Global Burden of Disease and gridded population data. The sectoral contribution to pediatric asthma from NO2 exposure (NO2-related asthma incidence: NINC) was estimated for different source categories to provide guidance to mitigation policies. We estimate 3.52 (2.1–6.0) million NINC per year globally, being about 14% of the total asthma incidence cases among children and adolescents. We find that emissions from land transportation are the leading contributor to NINC globally (∼44%), followed by the domestic burning of solid fuels (∼10.3%) and power generation from fossil fuels (∼8.7%). Biogenic emissions which are not anthropogenically induced may contribute ∼14% to the total NINC. Our results show large regional differences in source contributions, as the domestic burning of solid fuels is a main contributor to NINC in India and Nepal (∼25%), while emissions from shipping are the leading source in Scandinavian countries (∼40%), for example. While only 5% of all children and adolescents live in areas where NO2 exceeds the WHO annual guideline of 21.25 ppb (40 μg m−3) for NO2, about 90% of the NINC is found in regions that meet the WHO guideline, related to the uneven distribution of children and adolescents in the population. This suggests the need for stricter policies to reduce NO2 exposure, and revisiting the current WHO guideline to reduce the health risks of children and adolescents.

Copernicus Atmosphere Monitoring Service TEMPOral profiles (CAMS-TEMPO): global and European emission temporal profile maps for atmospheric chemistry modelling

Abstract. We present the Copernicus Atmosphere Monitoring Service TEMPOral profiles (CAMS-TEMPO), a dataset of global and European emission temporal profiles that provides gridded monthly, daily, weekly and hourly weight factors for atmospheric chemistry modelling. CAMS-TEMPO includes temporal profiles for the priority air pollutants (NOx; SOx; NMVOC, non-methane volatile organic compound; NH3; CO; PM10; and PM2.5) and the greenhouse gases (CO2 and CH4) for each of the following anthropogenic source categories: energy industry (power plants), residential combustion, manufacturing industry, transport (road traffic and air traffic in airports) and agricultural activities (fertilizer use and livestock). The profiles are computed on a global 0.1 × 0.1∘ and regional European 0.1 × 0.05∘ grid following the domain and sector classification descriptions of the global and regional emission inventories developed under the CAMS programme. The profiles account for the variability of the main emission drivers of each sector. Statistical information linked to emission variability (e.g. electricity production and traffic counts) at national and local levels were collected and combined with existing meteorology-dependent parametrizations to account for the influences of sociodemographic factors and climatological conditions. Depending on the sector and the temporal resolution (i.e. monthly, weekly, daily and hourly) the resulting profiles are pollutant-dependent, year-dependent (i.e. time series from 2010 to 2017) and/or spatially dependent (i.e. the temporal weights vary per country or region). We provide a complete description of the data and methods used to build the CAMS-TEMPO profiles, and whenever possible, we evaluate the representativeness of the proxies used to compute the temporal weights against existing observational data. We find important discrepancies when comparing the obtained temporal weights with other currently used datasets. The CAMS-TEMPO data product including the global (CAMS-GLOB-TEMPOv2.1, https://doi.org/10.24380/ks45-9147, Guevara et al., 2020a) and regional European (CAMS-REG-TEMPOv2.1, https://doi.org/10.24380/1cx4-zy68, Guevara et al., 2020b) temporal profiles are distributed from the Emissions of atmospheric Compounds and Compilation of Ancillary Data (ECCAD) system (https://eccad.aeris-data.fr/, last access: February 2021).

Revisiting Ranking of Academic Institutions

The article provides an overview of ranking systems including its historical evolution, use of rankings by different stakeholders, ranking indicators, merits and demerits of different ranking systems and performance of Indian universities in in past one decade in global ranking systems. The article briefly describes nine global ranking systems and compares them based on weightage assigned to different categories of indicators and source of data used for ranking of HEIs. Lastly, article provides statistical inter-correlation amongst various ranking systems as well as intra-correlation within ranking systems at interval of five years (2011:2015; and 2016:2020) and 10 years (2011-2020).

Tool to Retrieve Less-Filtered Information from the Internet

While users benefit greatly from the latest communication technology, with popular platforms such as social networking services including Facebook or search engines such as Google, scientists warn of the effects of a filter bubble at this time. A solution to escape from filtered information is urgently needed. We implement an approach based on the mechanism of a metasearch engine to present less-filtered information to users. We develop a practical application named MosaicSearch to select search results from diversified categories of sources collected from multiple search engines. To determine the power of MosaicSearch, we conduct an evaluation to assess retrieval quality. According to the results, MosaicSearch is more intelligent compared to other general-purpose search engines: it generates a smaller number of links while providing users with almost the same amount of objective information. Our approach contributes to transparent information retrieval. This application helps users play a main role in choosing the information they consume.

Anthropogenic Mercury Release Flow in China

China is the largest emitter of anthropogenic mercury worldwide. Implementation of the Minamata Convention on Mercury will significantly impact the development, use, and management of mercury resources. Chinese mercury management policies require significant adjustment. There is an urgent need to develop a current national mercury inventory to estimate mercury inputs and outputs by source category, and to clarify the distributions to various environmental scenarios. Here, the mercury releases are quantitatively analysed to facilitate the implementation of strategic mercury management policies in China. First, the mercury inputs and outputs by source categories in 2016 are quantified and then the mercury distributions to various environmental and intermediate sinks are estimated. The total mercury input was 5,116 t in 2016, of which 77% was attributable to mineral production. In total, 3,083 t were released into various environmental and intermediate reservoirs. Of this total, 53.8 % was intentional uses, followed by extraction and combustion (26.5%), and mineral production (19.6 %); 1,501 t were released into air, water, and land, of which extraction and combustion accounted for 48.6 % followed by mineral production (25.7 %) and intentional uses (25.6 %).

Inventory and Characteristics of Small-Scale PM2.5 in a District of Tianjin

Based on the activity level data of PM2.5 pollution sources in a certain area around Tianjin City, corresponding emission factors were selected to construct a 0.5km×0.5km small-scale PM2.5 emission inventory for the area in 2017. The results showed that in 2017, an area around the city of Tianjin emitted 3,509.91 tons of PM2.5. According to the emission inventory of PM2.5, in terms of the emission categories of pollution sources, the emission proportion of dust sources, process sources, road mobile sources and fixed combustion sources is 48%, 38%, 6% and 5% respectively. From the perspective of pollution sources, steel emissions accounted for 35% of the overall PM2.5 emissions, and road dust emissions accounted for 25.4% of the overall emissions. In addition, spatial distribution results show that there are pollution sources such as 1 boiler, scattered coal, some enterprises, several main roads, several construction sites and a large number of restaurants within a 3-kilometer radius of a monitoring station in a district around the city of Tianjin. The PM2.5 emitted by these pollution sources will directly affect the PM2.5 concentration in the district. There are still some uncertainties in this list, so the data of activity level, such as road traffic flow, need to be further detailed, and the localization study of emission factors should be further carried out, so as to provide a scientific basis for the formulation of regional pollution prevention strategies.