scholarly journals Recent decrease trend of atmospheric mercury concentrations in East China: the influence of anthropogenic emissions

2018 ◽  
Author(s):  
Yi Tang ◽  
Shuxiao Wang ◽  
Qingru Wu ◽  
Kaiyun Liu ◽  
Long Wang ◽  
...  
Keyword(s):  
Air Pollutants ◽  
Sampling Period ◽  
Atmospheric Mercury ◽  
Meteorological Conditions ◽  
East China ◽  
Anthropogenic Emissions ◽  
Chongming Island

Abstract. Measurements of gaseous elemental Hg (GEM), other air pollutants including SO2, NOx, O3, PM2.5, CO, and meteorological conditions were carried out at Chongming Island in East China from March 1 in 2014 to December 31 in 2016. During the sampling period, GEM concentrations significantly decreased from 2.68 ± 1.07 ng m−3 in 2014 to 1.60 ± 0.56 ng m−3 in 2016. Monthly mean GEM concentrations showed a significant decrease with a rate of −0.60 ng m−3 yr−1 (R2 = 0.6389, p 

scholarly journals Recent decrease trend of atmospheric mercury concentrations in East China: the influence of anthropogenic emissions

2018 ◽  
Vol 18 (11) ◽  
pp. 8279-8291 ◽  
Author(s):  
Yi Tang ◽  
Shuxiao Wang ◽  
Qingru Wu ◽  
Kaiyun Liu ◽  
Long Wang ◽  
...  
Keyword(s):  
Power Plants ◽  
Source Region ◽  
Elemental Mercury ◽  
Sampling Period ◽  
Atmospheric Mercury ◽  
Cement Clinker ◽  
East China ◽  
Air Pollution Control ◽  
Significance Level ◽  
Chongming Island

Abstract. Measurements of gaseous elemental mercury (GEM), other air pollutants, including SO2, NOx, O3, PM2.5, and CO, and meteorological conditions were carried out at Chongming Island in East China from 1 March 2014 to 31 December 2016. During the sampling period, GEM concentrations significantly decreased from 2.68 ± 1.07 ng m−3 in 2014 (March to December) to 1.60 ± 0.56 ng m−3 in 2016 (March to December). Monthly mean GEM concentration showed a significant decrease, at a rate of -0.60±0.08 ng m−3 yr−1 (R2=0.64, p < 0.01 significance level). Combining the analysis of the potential source contribution function (PSCF), principle component analysis (PCA), and the emission inventory, we found that the Yangtze River Delta (YRD) region was the dominant source region of GEM in Chongming Island and the main source industries included coal-fired power plants, coal-fired industrial boilers, and cement clinker production. We further quantified the effect of emission change on the air Hg concentration variations at Chongming Island through a coupled method of trajectory clusters and air Hg concentrations. It was found that the reduction of domestic emissions was the main driver of GEM decline in Chongming Island, accounting for 70 % of the total decline. The results indicated that air pollution control policies targeting SO2, NOx, and particulate matter reductions had significant co-benefits on GEM.

scholarly journals Solar Brightening/Dimming over China’s Mainland: Effects of Atmospheric Aerosols, Anthropogenic Emissions, and Meteorological Conditions

2020 ◽  
Vol 13 (1) ◽  
pp. 88
Author(s):  
Hejin Fang ◽  
Wenmin Qin ◽  
Lunche Wang ◽  
Ming Zhang ◽  
Xuefang Yang
Keyword(s):  
Atmospheric Aerosols ◽  
Southern China ◽  
Influencing Factor ◽  
Precipitable Water ◽  
Northwest China ◽  
Meteorological Conditions ◽  
Anthropogenic Emissions ◽  
Main Role ◽  
Surface Solar Radiation ◽  
Climate Change Research

Surface solar radiation (SSR) is the main factor affecting the earth’s climate and environment and its variations and the reason for these variations are an important part of climate change research. In this research, we investigated the long-term variations of SSR during 1984–2016 and the quantitative influences of atmospheric aerosols, anthropogenic emissions, and meteorological conditions on SSR over China’s mainland. The results show the following: (1) The annual average SSR values had a decline trend at a rate of −0.371 Wm−2 yr−1 from 1984 to 2016 over China. (2) The aerosol optical depth (AOD) plays the main role in inducing variations in SSR over China, with r values of −0.75. Moreover, there are marked regional differences in the influence of anthropogenic emissions and meteorological conditions on SSR trends. (3) From a regional perspective, AOD is the main influencing factor on SSR in northeast China (NEC), Yunnan Plateau and surrounding regions (YPS), North China (NC), and Loess Plateau (LP), with r values of −0.65, −0.60, −0.89, and −0.50, respectively. However, the main driving factors for SSR in northwest China (NWC) are “in cloud optical thickness of all clouds” (TAUTOT) (−0.26) and black carbon (BC) anthropogenic emissions (−0.21). TAUTOT (−0.39) and total precipitable water vapor (TQV) (−0.29) are the main influencing factors of SSR in the middle-lower Yangtze Plain (MYP). The main factors that influence SSR in southern China (SC) are surface pressure (PS) (−0.66) and AOD (−0.43). This research provides insights in understanding the variations of SSR and its relationships with anthropogenic conditions and meteorological factors.

scholarly journals Satellite constraint for emissions of nitrogen oxides from anthropogenic, lightning and soil sources over East China on a high-resolution grid

2011 ◽  
Vol 11 (11) ◽  
pp. 29807-29843 ◽  
Author(s):  
J.-T. Lin
Keyword(s):  
High Resolution ◽  
Nitrogen Oxides ◽  
A Priori ◽  
East China ◽  
Anthropogenic Emissions ◽  
Ozone Monitoring Instrument ◽  
Vertical Column ◽  
The North ◽  
Sensitivity Tests ◽  
Soil Emissions

Abstract. Vertical column densities (VCDs) of tropospheric nitrogen dioxide (NO2) retrieved from space provide valuable information to estimate emissions of nitrogen oxides (NOx) inversely. Accurate emission attribution to individual sources, important both for understanding the global biogeochemical cycling of nitrogen and for emission control, remains difficult. This study presents a regression-based multi-step inversion approach to estimate emissions of NOx from anthropogenic, lightning and soil sources individually for 2006 over East China on a 0.25° long × 0.25° lat grid, employing the DOMINO product version 2 retrieved from the Ozone Monitoring Instrument. The nested GEOS-Chem model for East Asia is used to simulate the seasonal variations of different emission sources and impacts on VCDs of NO2 for the inversion purpose. Sensitivity tests are conducted to evaluate key assumptions embedded in the inversion process. The inverse estimate suggests annual budgets of about 7.1 TgN (±38%), 0.22 TgN (±46%), and 0.40 TgN (±48%) for the a posteriori anthropogenic, lightning and soil emissions, respectively, each about 24% higher than the respective a priori values. The enhancements in anthropogenic emissions are largest in cities and areas with extensive use of coal, particularly in the north in winter, as evident on the high-resolution grid. Derived soil emissions are consistent with recent bottom-up estimates. They are each less than 6% of anthropogenic emissions annually, increasing to about 13% for July. Overall, anthropogenic emissions are found to be the dominant source of NOx over East China with important implications for nitrogen control.

scholarly journals China’s emission control strategies have suppressed unfavorable influences of climate on wintertime PM2.5 concentrations in Beijing since 2002

2020 ◽  
Author(s):  
Meng Gao ◽  
Kaili Lin ◽  
Shiqing Zhang ◽  
Ken kin lam Yung
Keyword(s):  
Control Strategies ◽  
Emission Control ◽  
Field Measurements ◽  
Meteorological Conditions ◽  
Control Measures ◽  
Anthropogenic Emissions ◽  
Recent Climate ◽  
Decadal Variations ◽  
Haze Days ◽  
Emission Control Measures

&lt;p&gt;Severe wintertime PM2.5 pollution in Beijing has been receiving increasing worldwide attention, yet the decadal variations remain relatively unexplored. Combining field measurements and model simulations, we quantified the relative influences of anthropogenic emissions and meteorological conditions on PM2.5 concentrations in Beijing overwinters of 2002-2016. Between the winters of 2011 and 2016, stringent emission control measures resulted in a 21% decrease in mean mass concentrations of PM2.5 in Beijing, with 7 fewer haze days per winter on average. Given the overestimation of PM2.5 by model, the effectiveness of stringent emission control measures might have been slightly overstated. With fixed emissions, meteorological conditions over the study period would have led to an increase of haze in Beijing, but the strict emission control measures have suppressed the unfavorable influences of recent climate. The unfavorable meteorological conditions are attributed to the weakening of the East Asia Winter Monsoon associated particularly with an increase in pressure associated with the Aleutian low.&lt;/p&gt;

scholarly journals Chemical and meteorological influences on the lifetime of NO<sub>3</sub> at a semi-rural mountain site during PARADE

2016 ◽  
Vol 16 (8) ◽  
pp. 4867-4883 ◽  
Author(s):  
N. Sobanski ◽  
M. J. Tang ◽  
J. Thieser ◽  
G. Schuster ◽  
D. Pöhler ◽  
...  
Keyword(s):  
Loss Rate ◽  
Trace Gases ◽  
Meteorological Conditions ◽  
Biogenic Emissions ◽  
Anthropogenic Emissions ◽  
Air Masses ◽  
Mixing Ratios ◽  
Criegee Intermediates ◽  
Mountain Site ◽  
Meteorological Influences

Abstract. Through measurements of NO2, O3 and NO3 during the PARADE campaign (PArticles and RAdicals, Diel observations of mEchanisms of oxidation) in the German Taunus mountains we derive nighttime steady-state lifetimes (τss) of NO3 and N2O5. During some nights, high NO3 (∼ 200 pptv) and N2O5 (∼ 1 ppbv) mixing ratios were associated with values of τss that exceeded 1 h for NO3 and 3 h for N2O5 near the ground. Such long boundary-layer lifetimes for NO3 and N2O5 are usually only encountered in very clean/unreactive air masses, whereas the PARADE measurement site is impacted by both biogenic emissions from the surrounding forest and anthropogenic emissions from the nearby urbanised/industrialised centres. Measurement of several trace gases which are reactive towards NO3 indicates that the inferred lifetimes are significantly longer than those calculated from the summed loss rate. Several potential causes for the apparently extended NO3 and N2O5 lifetimes are examined, including additional routes to formation of NO3 and the presence of a low-lying residual layer. Overall, the most likely cause of the anomalous lifetimes are related to the meteorological conditions, though additional NO3 formation due to reactions of Criegee intermediates may contribute.

Atmospheric mercury sources in a coastal-urban environment: A case study in Boston, Massachusetts, USA.

2021 ◽  
Author(s):  
Hélène Angot ◽  
Emma Rutkowski ◽  
Maryann Sargent ◽  
Steven C. Wofsy ◽  
Lucy R. Hutyra ◽  
...  
Keyword(s):  
Human Health ◽  
Urban Environment ◽  
Atmospheric Mercury ◽  
Anthropogenic Emissions ◽  
Environmental Toxicant ◽  
Local Policies

Mercury (Hg) is an environmental toxicant dangerous to human health and the environment. Its anthropogenic emissions are regulated by global, regional, and local policies. Here, we investigate Hg sources in...

Measurements and Comparative Air Quality Analysis of a Goat Farm Operation

2019 ◽  
Vol 62 (6) ◽  
pp. 1723-1733
Author(s):  
Arndreya Howard ◽  
Venkata S. V. Botlaguduru ◽  
Hongbo Du ◽  
Raghava R. Kommalapati ◽  
Ziaul Huque
Keyword(s):  
Hydrogen Sulfide ◽  
Air Quality ◽  
Solar Radiation ◽  
Multiple Regression ◽  
Air Pollutants ◽  
Emission Rate ◽  
Particle Diameter ◽  
Ambient Air ◽  
Meteorological Conditions ◽  
Goat Farm

Abstract. Air pollutants such as hydrogen sulfide, ammonia, particulate matter (PM10 and PM2.5), methane, and volatile organic compounds (VOCs) are harmful to the respiratory systems of humans and animals. Livestock facilities have been documented as a major source of dangerous air pollutants; however, there is a lack of data on the emissions from goat farms. This study investigated a goat farm in Texas to evaluate the emission levels and determine the correlation of meteorological conditions with these pollutants. Two locations on the goat farm were selected for monitoring: inside a goat barn, and at a manure lagoon. The monitoring campaign was conducted over a 53-day period during winter and summer seasons. Carbon dioxide, ozone, nitrous oxide, ammonia, PM10, PM2.5, hydrogen sulfide, methane, and VOCs were measured to determine hourly average concentrations using chemiluminescent instruments. An analysis of meteorological conditions using multiple regression was conducted to investigate probable correlations between emission rates and characteristic climate data, such as temperature, humidity, barometric pressure, and solar radiation. Particle size distributions of PM10 and PM2.5 were evaluated for the two monitoring locations during the different seasons to determine the typical particle diameter and the impact of season on particle diameter. The highest emission rate of 364.4 ±50 g m-2 d-1 occurred at the manure lagoon for methane, which contributed the most to the overall emissions at this animal operation. The regression results for the manure lagoon had the highest positive correlations for ozone with temperature and solar radiation. The outdoor meteorological conditions had the most significant influence on pollutants at both locations. Therefore, meteorological conditions are instrumental in the intensity of the air pollutants found on animal farms. The particle diameters ranged from 0.1 to 6.0 µm in the goat barn and from 0.3 to 1.0 µm at the manure lagoon. Even though moderate levels of emissions were monitored at this facility, the emissions from the goat farm do not pose a risk to human health and do not significantly impact the ambient air quality when compared to other livestock facilities.HighlightsEmissions from a goat farm were measured inside a goat barn and at a manure lagoon over summer and winter seasons.The highest methane emission rate of 364.4 ±50 g m-2 d-1 occurred at the manure lagoon during summer.Meteorological conditions significantly influenced emissions at both locations, especially for O3 at the manure lagoon.Emissions from goat farm operations are much lower than those from cow, swine, and chicken farm operations. Keywords: Air quality, Ammonia, Emissions, Goat farm, Methane, Multiple regression analysis.

scholarly journals Potential sources and processes affecting speciated atmospheric mercury at Kejimkujik National Park, Canada

2016 ◽  
Author(s):  
Xiaohong Xu ◽  
Yanying Liao ◽  
Irene Cheng ◽  
Leiming Zhang
Keyword(s):  
Air Pollutants ◽  
National Park ◽  
Treatment Options ◽  
Model Performance ◽  
Principal Component ◽  
Elemental Mercury ◽  
Atmospheric Mercury ◽  
Strong Impact ◽  
Good For ◽  
Kejimkujik National Park

Abstract. Source apportionment analysis was conducted with Positive Matrix Factorization (PMF) and Principal Component Analysis (PCA) methods using concentrations of speciated mercury (Hg), i.e., gaseous elemental mercury (GEM), gaseous oxidized mercury (GOM), and particulate-bound mercury (PBM), and other air pollutants collected at Kejimkujik National Park, Nova Scotia, Canada in 2009 and 2010. The results were largely consistent between the two years for both methods. The same four source factors were identified in each year using PMF method. In both years, factor Photochemistry and Re-emission had the largest contributions to atmospheric Hg, while the contributions of Combustion Emission and Industrial Sulfur varied slightly between the two years. Four components were extracted with air pollutants only in each year using PCA method. Consistency between the results of PMF and PCA include, 1) most or all PMF factors overlapped with PCA components, 2) both methods suggest strong impact of photochemistry, but little association between ambient Hg and sea salt, 3) shifting of PMF source profiles and source contributions from one year to another was echoed in PCA. Inclusion of meteorological parameters led to identification of an additional component – Hg Wet Deposition in PCA, while it did not affect the identification of other components. The PMF model performance was comparable in 2009 and 2010. Among the three Hg forms, the agreement between predicted and observed annual mean concentrations were excellent for GEM, very good for PBM and acceptable for GOM. However, on daily basis, the agreement was very good for GEM, but poor for GOM and PBM. Sensitivity tests suggest that increasing sample size by imputation is not effective in improving model performance, while reducing the fraction of concentrations below method detection limit, by either scaling GOM and PBM to higher concentrations or combining them to reactive mercury, is effective. Most of the data treatment options considered had little impact on the source identification/contribution.

Sign in / Sign up

Export Citation Format

Share Document