scholarly journals Evaluations of Surface PM10 Concentration and Chemical Compositions in MERRA-2 Aerosol Reanalysis over Central and Eastern China

2021 ◽  
Vol 13 (7) ◽  
pp. 1317
Author(s):  
Xiaodan Ma ◽  
Peng Yan ◽  
Tianliang Zhao ◽  
Xiaofang Jia ◽  
Jian Jiao ◽  
...  
Keyword(s):  
Eastern China ◽  
Mainland China ◽  
Chemical Components ◽  
Chemical Compositions ◽  
Observation Data ◽  
Causative Factors ◽  
Routine Sampling ◽  
Aerosol Compositions ◽  
Modern Era

The chemical composition dataset of Aerosol Reanalysis of NASA’s Modern-Era Retrospective Analysis for Research and Application, version 2 (MERRAero) has not been thoroughly evaluated with observation data in mainland China due to the lack of long-term chemical components data. Using the 5-year data of PM10 mass concentrations and chemical compositions obtained from the routine sampling measurements at the World Meteorological Organization the Global Atmosphere Watch Programme regional background stations, Jing Sha (JS) and Lin’An (LA), in central and eastern China, we comprehensively evaluate the surface PM10 concentrations and chemical compositions such as sulfate (SO42−), organic carbon (OC) and black carbon (BC) derived from MERRAero. Overall, the concentrations of PM10, SO42−, OC and BC from the MERRAero agreed well with the measurements, despite a slight and consistent overestimation of BC concentrations and a moderate and persistent underestimation of PM10 concentrations throughout the study period. The MERRAero reanalysis of aerosol compositions performs better during the summertime than wintertime. By considering the nitrate particles in PM10 reconstruction, MERRAero performance can be significantly improved. The unreasonable seasonal variations of PM10 chemical compositions at station LA by MERRAero could be causative factors for the larger MERRAero discrepancies during 2016–2017 than the period of 2011–2013.

scholarly journals MICS-Asia III: Multi-model comparison and evaluation of aerosol over East Asia

2019 ◽  
Author(s):  
Lei Chen ◽  
Yi Gao ◽  
Meigen Zhang ◽  
Joshua S. Fu ◽  
Jia Zhu ◽  
...  
Keyword(s):  
East Asia ◽  
Model Comparison ◽  
Process Analysis ◽  
Eastern China ◽  
Phase Iii ◽  
Chemical Components ◽  
Chemical Compositions ◽  
Air Pollution Control ◽  
Different Seasons ◽  
Simulation Results

Abstract. Fourteen chemical transport models (CTMs) participate in the MICS–Asia Phase III Topic 1. Their simulation results are compared with each other and with an extensive set of measurements, aiming to evaluate the current multi–scale air quality models’ ability in simulating aerosol species and to document similarities and differences among model performances, also to reveal the characteristics of aerosol chemical components over big cities in East Asia. In general, all participant models can reproduce the spatial distribution and seasonal variability of aerosol concentrations in the year 2010, and multi–model ensemble mean (EM) shows better performance than most individual models, with Rs ranging from 0.65 (NO3−) to 0.83 (PM2.5). Underestimations of BC (NMB = −17.0 %), SO42− (NMB = −19.1 %) and PM10 (NMB = −32.6 %) are simulated by EM, but positive biases are shown in NO3− (NMB = 4.9 %), NH4+ (NMB = 14.0 %) and PM2.5 (NMB = 4.4 %). Simulation results of BC, OC, SO42−, NO3− and NH4+ among CTMs are in good agreements, especially over polluted areas, such as the eastern China and the northern part of India. But large coefficients of variations (CV > 1.5) are also calculated over arid and semi–arid regions. This poor consistency among CTMs may attribute to their different processing capacities for dust aerosols. According to the simulation results in the six Asian cities from EM, different air–pollution control plans should be made due to their different major air pollutants in different seasons. Although a more considerable capacity for reproducing the concentrations of aerosol chemical compositions and their variation tendencies is shown in current CTMs by comparing statistics (e.g. RMSE and R) between MICS–Asia Phase II and Phase III, detailed process analysis and a fully understanding of the source–receptor relationship in each process may be helpful to explain and to reduce large diversities of simulated aerosol concentrations among CTMs, and these may be the potential development directions for future modeling studies in East Asia.

scholarly journals Characteristics of PM<sub>2.5</sub> mass concentrations and chemical species in urban and background areas of China: emerging results from the CARE-China network

2018 ◽  
Author(s):  
Zirui Liu ◽  
Wenkang Gao ◽  
Yangchun Yu ◽  
Bo Hu ◽  
Jinyuan Xin ◽  
...  
Keyword(s):  
Chemical Species ◽  
Central China ◽  
Research Network ◽  
Mitigation Measures ◽  
Chemical Components ◽  
Chemical Compositions ◽  
East Central ◽  
Urban Sites ◽  
Mass Concentrations

Abstract. The Campaign on atmospheric Aerosol REsearch network of China (CARE-China) is a long-term project for the study of the spatiotemporal distributions of physical aerosol characteristics as well as the chemical components and optical properties of aerosols over China. This study presents the first long-term datasets from this project, including three years of observations of online PM2.5 mass concentrations (2012–2014) and one year of observations of PM2.5 compositions (2012–2013) from the CARE-China network. The average PM2.5 concentrations at 20 urban sites is 73.2 μg/m3 (16.8–126.9 μg/m3), which was three times higher than the average value from the 12 background sites (11.2–46.5 μg/m3). The PM2.5 concentrations are generally higher in east-central China than in the other parts of the country due to their relative large particulate matter (PM) emissions and the unfavorable meteorological conditions for pollution dispersion. A distinct seasonal variability of the PM2.5 is observed, with highs in the winter and lows during the summer at urban sites. Inconsistent seasonal trends were observed at the background sites. Bimodal and unimodal diurnal variation patterns were identified at both urban and background sites. The chemical compositions of PM2.5 at six paired urban and background sites located within the most polluted urban agglomerations and cleanest regions of China were analyzed. The major PM2.5 constituents across all the urban sites are organic matter (OM, 26.0 %), SO42− (17.7 %), mineral dust (11.8 %), NO3− (9.8 %), NH4+ (6.6 %), elemental carbon (EC) (6.0 %), Cl− (1.2 %) at 45 % RH and residual matter (20.7 %). Similar chemical compositions of PM2.5 were observed at background sites but were associated with higher fractions of OM (33.2 %) and lower fractions of NO3− (8.6 %) and EC (4.1 %). Significant variations of the chemical species were observed among the sites. At the urban sites, the OM ranged from 12.6 μg/m3 (Lhasa) to 23.3 μg/m3 (Shenyang), the SO42− ranged from 0.8 μg/m3 (Lhasa) to 19.7 μg/m3 (Chongqing), the NO3− ranged from 0.5 μg/m3 (Lhasa) to 11.9 μg/m3 (Shanghai) and the EC ranged from 1.4 μg/m3 (Lhasa) to 7.1 μg/m3 (Guangzhou). The PM2.5 chemical species at the background sites exhibited larger spatial heterogeneities than those at urban sites, suggesting the different contributions from regional anthropogenic or natural emissions and from the long-range transport to background areas. Notable seasonal variations of PM2.5 polluted days were observed, especially for the megacities in east-central China, resulting in frequent heavy pollution episodes occurring during the winter. The evolution of the PM2.5 chemical compositions on polluted days was similar for the urban and nearby background sites, suggesting the significant regional pollution characteristics of the most polluted areas of China. However, the chemical species dominating the evolutions of the heavily polluted events were different in these areas, indicating that unique mitigation measures should be developed for different regions of China. This analysis reveals the spatial and seasonal variabilities of the urban and background aerosol concentrations on a national scale and provides insights into their sources, processes, and lifetimes.

scholarly journals Significant reduction of PM<sub>2.5</sub> in eastern China due to regional-scale emission control: evidence from SORPES in 2011–2018

2019 ◽  
Vol 19 (18) ◽  
pp. 11791-11801 ◽  
Author(s):  
Aijun Ding ◽  
Xin Huang ◽  
Wei Nie ◽  
Xuguang Chi ◽  
Zheng Xu ◽  
...  
Keyword(s):  
Eastern China ◽  
Regional Scale ◽  
Substantial Reduction ◽  
Emission Control ◽  
Early Summer ◽  
Chemical Components ◽  
Air Pollution Control ◽  
Haze Pollution ◽  
The Impact

Abstract. Haze pollution caused by PM2.5 is the largest air quality concern in China in recent years. Long-term measurements of PM2.5 and the precursors and chemical speciation are crucially important for evaluating the efficiency of emission control, understanding formation and transport of PM2.5 associated with the change of meteorology, and accessing the impact of human activities on regional climate change. Here we reported long-term continuous measurements of PM2.5, chemical components, and their precursors at a regional background station, the Station for Observing Regional Processes of the Earth System (SORPES), in Nanjing, eastern China, since 2011. We found that PM2.5 at the station has experienced a substantial decrease (−9.1 % yr−1), accompanied by even a very significant reduction of SO2 (−16.7 % yr−1), since the national “Ten Measures of Air” took action in 2013. Control of open biomass burning and fossil-fuel combustion are the two dominant factors that influence the PM2.5 reduction in early summer and winter, respectively. In the cold season (November–January), the nitrate fraction was significantly increased, especially when air masses were transported from the north. More NH3 available from a substantial reduction of SO2 and increased oxidization capacity are the main factors for the enhanced nitrate formation. The changes of year-to-year meteorology have contributed to 24 % of the PM2.5 decrease since 2013. This study highlights several important implications on air pollution control policy in China.

scholarly journals Evaluating the Drought-Monitoring Utility of GPM and TRMM Precipitation Products over Mainland China

2021 ◽  
Vol 13 (20) ◽  
pp. 4153
Author(s):  
Shuai Cheng ◽  
Weiguang Wang ◽  
Zhongbo Yu
Keyword(s):  
Real Time ◽  
Spatial Scales ◽  
Eastern China ◽  
Mainland China ◽  
Western China ◽  
Drought Monitoring ◽  
Ground Observation ◽  
Trmm Precipitation ◽  
Temporal And Spatial

The purpose of this study was to evaluate the applicability of medium and long-term satellite rainfall estimation (SRE) precipitation products for drought monitoring over mainland China. Four medium and long-term (19 a) SREs, i.e., the Tropical Rainfall Measuring Mission (TRMM) Multi-Satellite Precipitation Analysis (TMPA) 3B42V7, the Integrated Multi-satellitE Retrievals for Global Precipitation Measurement V06 post-real time Final Run precipitation products (IMF6), Global Rainfall Map in Near-real-time Gauge-calibrated Rainfall Product (GSMaP_Gauge_NRT) for product version 6 (GNRT6) and gauge-adjusted Global Satellite Mapping of Precipitation V6 (GGA6) were considered. The accuracy of the four SREs was first evaluated against ground observation precipitation data. The Standardized Precipitation Evapotranspiration Index (SPEI) based on four SREs was then compared at multiple temporal and spatial scales. Finally, four typical drought-influenced regions, i.e., the Northeast China Plain (NEC), Huang-Huai-Hai Plain (3HP), Yunnan–Guizhou Plateau (YGP) and South China (SC) were chosen as examples to analyze the ability of four SREs to capture the temporal and spatial changes of typical drought events. The results show that compared with GNRT6, the precipitation estimated by GGA6, IMF6 and 3B42V7 are in better agreement with the ground observation results. In the evaluation using SPEI, the four SREs performed well in eastern China but have large uncertainty in western China. GGA6 and IMF6 perform superior to GNRT6 and 3B42V7 in estimating SPEI and identifying typical drought events and behave almost the same. In general, GPM precipitation products have great potential to substitute TRMM precipitation products for drought monitoring. Both GGA6 and IMF6 are suitable for historical drought analysis. Due to the shorter time latency of data release and good performance in the eastern part of mainland China, GNRT6 and GGA6 might play a role for near real-time drought monitoring in the area. The results of this research will provide reference for the application of the SREs for drought monitoring in the GPM era.

scholarly journals Significant reduction of PM<sub>2.5</sub> in eastern China due to regional-scale emission control: Evidences from the SORPES station, 2011–2018

2019 ◽  
Author(s):  
Aijun Ding ◽  
Xin Huang ◽  
Wei Nie ◽  
Xuguang Chi ◽  
Zheng Xu ◽  
...  
Keyword(s):  
Eastern China ◽  
Regional Scale ◽  
Substantial Reduction ◽  
Emission Control ◽  
Early Summer ◽  
Chemical Components ◽  
Air Pollution Control ◽  
Haze Pollution ◽  
The Impact

Abstract. Haze pollution caused by PM2.5 is the largest air quality concern in China in recent years. Long-term measurements of PM2.5 and the precursors and chemical speciation is crucially important for evaluating the efficiency of emission control, understanding formation and transport of PM2.5 associated with the change of meteorology and for accessing the impact of human activities to regional climate change. Here we reported long-term continuous measurements of PM2.5, chemical components, and their precursors at a regional background station, the Station for Observing Regional Processes of the Earth System (SORPES), in Nanjing eastern China since 2011. We found that PM2.5 at the station has experienced a substantial decrease (−9.1 %/yr), accompanied with even much significant reduction of SO2 (−16.7 %/yr), since the national "Ten measures" for air took action in 2013. Control of open biomass burning and fossil-fuel combustion are the two dominant factors that influence the PM2.5 reduction in early summer and winter, respectively. In cold season (November–January), increased nitrate fraction was observed with more NH3 available from a substantial reduction of sulfate, and the change of year-to-year meteorology contributed to 24 % of the PM2.5 decrease since 2013. This study highlights several important implications on air pollution control policy in China.

TOXIC PROPERTIES AND INTAKE SYMPTOMS OF SOME WILD PLANTS IN RELATION TO REPORTED FROM THE FOREST OF NORTH WEST SATPUDA REGION OF MAHARASTRA, INDIA

2017 ◽  
Vol 23 (2) ◽  
Author(s):  
SANJAY A. KHAIRNAR
Keyword(s):  
Secondary Phase ◽  
Wild Plants ◽  
Chemical Components ◽  
World Population ◽  
Poisonous Plants ◽  
North West ◽  
Toxic Plants ◽  
Datura Metel ◽  
Croton Tiglium ◽  
Modern Era

In modern era about 80% of the world population depends on herbal alternative system of medicine. Seventy thousand plants are used in medicine and about 2000 plants are used in Indian Ayurveda. The activities of the curative plants are evaluated by their chemical components. Few of them are important as a medicine but also posses poisonous or toxic properties. The toxicity is produced in them due to the synthesis of toxic chemical compounds may be in primary or secondary phase of their life. Most of the users of such medicinal plants in crude form are tribal and peoples living in the forests and their domestic stock . Most of the time these peoples may not aware about the toxicity of such plants used by them and probably get affected sometimes even leads to death. In the study area during the field survey of poisonous plants, information are gathered from the traditional practicing persons, cow boy and from shepherds. About 20 plant species belonging to 17 families are reported as a medicinal as well as toxic. From the available literature, nature of toxic compound and symptoms of their intake on human being are recorded. In the study area the plants like, Abrus precatorious commonly known as a Gunj or Gunjpala, Jatropha curcas , (Biodiesel plant), Croton tiglium (Jamalgota), Citrullus colocynthis (Kadu Indrawan, Girardinia diversifolia (Agya), Mucuna purriens (Khajkuairi), Euphorbia tirucali (Sher), E. ligularia (Sabarkand), Datura metel ( Kala Dhotara), Datura inoxia (Pandhara Dhotara) and Asparagus racemo-sus (Shatavari) etc . are some of the toxic plants used as a medicine and harmful also.

REPEATED LONG-TERM SPACE FLIGHTS: PROTEOMIC INVESTIGATIONS OF COSMONAUTS' BLOOD

2020 ◽  
Vol 54 (5) ◽  
pp. 15-22
Author(s):  
I.M. Larina ◽  
◽  
D.N. Kashirina ◽  
K.S. Kireev ◽  
A.I. Grigoriev ◽  
...  
Keyword(s):  
Bone Structure ◽  
Space Station ◽  
The Body ◽  
Coagulation Cascade ◽  
Chemical Components ◽  
Blood Proteins ◽  
Blood Indices ◽  
Before And After ◽  
Biochemical Indices

We performed the first ever comparative analysis of modifications in the proteome, ionogram and some other blood plasma biochemical indices of 18 male cosmonauts (44 ± 6 years of age) before and after maiden or repeated long-term missions to the Russian segment of the International space station (ISS RS). Levels of proteins, substrates and ions as well as chemical components were measured using the LC-MS-based proteomics and routine biochemical techniques. A total of 256 to 281 indices were investigated with the methods of descriptive statistic, regression analysis, and access to bioinformatics resources. It was shown that blood indices recovery from the maiden and repeated missions reflects changes in the body systems and goes at a various speed. The results of measurements made prior to launch and on day 7 after landing are dependent on the number of missions. The bioinformatics techniques showed that after maiden missions both the mediator proteins of alkaline phosphatase (AP) and blood proteins with reliably changing concentrations are associated with the bio-processes including stress, metabolism and DNA reparation, apoptosis, catabolism and proteolysis. During early re-adaptation from repeated missions the AP level was affected by bone remodeling, phosphorylation, angiogenesis and coagulation cascade suggesting a distinct and urgent trigger of the processes of bone structure and mineralization.

scholarly journals A global association between Covid-19 cases and airborne particulate matter at regional level

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Angelo Solimini ◽  
F. Filipponi ◽  
D. Alunni Fegatelli ◽  
B. Caputo ◽  
C. M. De Marco ◽  
...  
Keyword(s):  
Air Pollution ◽  
Particulate Matter ◽  
Negative Binomial ◽  
Numerical Models ◽  
Regional Level ◽  
Pollution Level ◽  
Observation Data ◽  
Cumulative Number ◽  
Mixed Effect

AbstractEvidences of an association between air pollution and Covid-19 infections are mixed and inconclusive. We conducted an ecological analysis at regional scale of long-term exposure to air-borne particle matter and spread of Covid-19 cases during the first wave of epidemics. Global air pollution and climate data were calculated from satellite earth observation data assimilated into numerical models at 10 km resolution. Main outcome was defined as the cumulative number of cases of Covid-19 in the 14 days following the date when > 10 cumulative cases were reported. Negative binomial mixed effect models were applied to estimate the associations between the outcome and long-term exposure to air pollution at the regional level (PM10, PM2.5), after adjusting for relevant regional and country level covariates and spatial correlation. In total we collected 237,749 Covid-19 cases from 730 regions, 63 countries and 5 continents at May 30, 2020. A 10 μg/m3 increase of pollution level was associated with 8.1% (95% CI 5.4%, 10.5%) and 11.5% (95% CI 7.8%, 14.9%) increases in the number of cases in a 14 days window, for PM2.5 and PM10 respectively. We found an association between Covid-19 cases and air pollution suggestive of a possible causal link among particulate matter levels and incidence of COVID-19.

scholarly journals Long-Term Observations of Beach Variability at Hasaki, Japan

2020 ◽  
Vol 8 (11) ◽  
pp. 871
Author(s):  
Masayuki Banno ◽  
Satoshi Nakamura ◽  
Taichi Kosako ◽  
Yasuyuki Nakagawa ◽  
Shin-ichi Yanagishima ◽  
...  
Keyword(s):  
Morphological Change ◽  
High Frequency ◽  
Climate Changes ◽  
Wave Climate ◽  
Time Interval ◽  
Observation Data ◽  
Beach Profile ◽  
Water Level Variations ◽  
Monthly Variations

Long-term beach observation data for several decades are essential to validate beach morphodynamic models that are used to predict coastal responses to sea-level rise and wave climate changes. At the Hasaki coast, Japan, the beach profile has been measured for 34 years at a daily to weekly time interval. This beach morphological dataset is one of the longest and most high-frequency measurements of the beach morphological change worldwide. The profile data, with more than 6800 records, reflect short- to long-term beach morphological change, showing coastal dune development, foreshore morphological change and longshore bar movement. We investigated the temporal beach variability from the decadal and monthly variations in elevation. Extremely high waves and tidal anomalies from an extratropical cyclone caused a significant change in the long-term bar behavior and foreshore slope. The berm and bar variability were also affected by seasonal wave and water level variations. The variabilities identified here from the long-term observations contribute to our understanding of various coastal phenomena.

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