An in-situ campaign of spectral measurements for monitoring the crop stress and planting area in Luancheng of North China Plain

2004 ◽  
Author(s):  
Shui-Sen Chen ◽  
Liang-Fu Chen ◽  
Qin-Huo Liu ◽  
Qing Xiao
Keyword(s):  
North China Plain ◽  
North China ◽  
Spectral Measurements

scholarly journals A new approach to estimate pollutant emissions based on trajectory modelling and its application in the North China Plain

2011 ◽  
Vol 11 (11) ◽  
pp. 31137-31158 ◽  
Author(s):  
W. Y. Xu ◽  
C. S. Zhao ◽  
P. F. Liu ◽  
L. Ran ◽  
N. Ma ◽  
...  
Keyword(s):  
Air Quality ◽  
North China Plain ◽  
North China ◽  
Pollutant Emissions ◽  
New Approach ◽  
The North ◽  
The North China Plain ◽  
Source Contributions ◽  
Co Emission

Abstract. Emission information is crucial for air quality modelling and air quality management. In this study, a new approach based on the understanding of the relationship between emissions and measured pollutant concentrations has been proposed to estimate pollutant emissions and source contributions. The retrieval can be made with single point in-situ measurements combined with backward trajectory analyses. The method takes into consideration the effect of meteorology on pollutant transport when evaluating contributions and is independent of energy statistics, therefore can provide frequent updates on emission information. The spatial coverage can be further improved by using measurements from several sites and combining the derived emission fields. The method was applied to yield the source distributions of black carbon (BC) and CO in the North China Plain (NCP) using in-situ measurements from the HaChi (Haze in China) Campaign and to evaluate contributions from specific areas to local concentrations at the measurement site. Results show that this method can yield a reasonable emission field for the NCP and can directly quantify areal source contributions. Major BC and CO emission source regions are Beijing, the western part of Tianjin and Langfang, Hebei, with Tangshan being an additional important CO emission source area. The source contribution assessment suggests that, aside from local emissions in Wuqing, Tianjin and Hebei S, SW (d < 100 km) are the greatest contributors to measured local concentrations, while emissions from Beijing contribute little during summertime.

scholarly journals Measurement Report: Spatial and vertical variability of aerosol optical properties during MOABAI mobile on-road campaign in North China Plain

2021 ◽  
Author(s):  
Ioana Elisabeta Popovici ◽  
Zhaoze Deng ◽  
Philippe Goloub ◽  
Xiangao Xia ◽  
Hongbin Chen ◽  
...  
Keyword(s):  
Total Mass ◽  
Mass Concentration ◽  
North China Plain ◽  
North China ◽  
Concentration Profiles ◽  
Heavy Pollution ◽  
Sun Photometer ◽  
Micro Pulse Lidar

Abstract. The North China Plain (NCP) has been experiencing serious air quality problems since the rapid urbanization and industrialization and has been the subject of many studies over the years. This work presents mapping at a fine scale of the aerosol spatial and vertical variability obtained during the MOABAI campaign (Mobile Observation of Atmosphere By vehicle-borne Aerosol measurement Instruments) using a van equipped with a micro-pulse LIDAR, a sun photometer and in situ instruments, performing on-road measurements. The campaign was conducted from 5 May to 23 May 2017 and had as a main objective to map the pollutants distribution in Beijing and NCP area. A summary of aerosol properties during all measurement days and a comprehensive case study along the industrial Binhai New Area near Tianjin are presented. The highest AOD at 440 nm (1.34 and 1.9) were recorded during two heavy pollution episodes on 18 May and 19 May 2017, respectively. The lowest PBL (Planetary Boundary Layer) heights (< 1500 m) were recorded during the heavy pollution events, correlated with the highest AOD. Transport of dust from Gobi Desert was captured during the mobile measurements, impacting Beijing in the 9–13 May period. Exploring the NCP outside Beijing provided datasets in regions with lack of aerosol observation sites and allowed mapping higher aerosol concentrations when passing by polluted cities in NCP (Baoding, Tianjin and Tangshan). In this study, we provide the first mass concentration profiles derived from a mobile micro-pulse LIDAR, making use of complementary information on aerosol type from sun photometer and in situ data. The case study of 17 May 2017 revealed mean extinction coefficients of 0.14 ± 0.10 km−1 at 532 nm and total mass concentration of 80 ± 62 μg m−3 in the PBL (< 2000 m) for the mobile transect from Tianjin to Tangshan along the coast of Bohai Sea. The highest extinction (0.56 km−1) and mass concentrations (404 μg m−3) were found in the industrial Binhai New Area. The PM10 and PM2.5 fractions of the total mass concentration profiles were separated using the columnar size distribution derived from sun photometer measurements. A general good agreement was found between the lidar-derived PM concentrations at surface level and the ones recorded at the closest air quality stations along the transect, with the only exception along the industrial region near Tianjin port, where emissions were highly variable.

scholarly journals In Situ Persulfate Oxidation of 1,2,3-Trichloropropane in Groundwater of North China Plain

2019 ◽  
Vol 16 (15) ◽  
pp. 2752 ◽  
Author(s):  
Hui Li ◽  
Zhantao Han ◽  
Yong Qian ◽  
Xiangke Kong ◽  
Ping Wang
Keyword(s):  
Removal Efficiency ◽  
North China Plain ◽  
North China ◽  
Removal Rate ◽  
Chlorinated Hydrocarbons ◽  
Contaminated Site ◽  
High Concentration ◽  
Chlorinated Hydrocarbon ◽  
Persulfate Oxidation

In situ injection of Fe(II)-activated persulfate was carried out to oxidize chlorinated hydrocarbons and benzene, toluene, ethylbenzene, and xylene (BTEX) in groundwater in a contaminated site in North China Plain. To confirm the degradation of contaminants, an oxidant mixture of persulfate, ferrous sulfate, and citric acid was mixed with the main contaminants including 1,2,3-trichloropropane (TCP) and benzene before field demonstration. Then the mixed oxidant solution of 6 m3 was injected into an aquifer with two different depths of 8 and 15 m to oxidize a high concentration of TCP, other kinds of chlorinated hydrocarbons, and BTEX. In laboratory tests, the removal efficiency of TCP reached 61.4% in 24 h without other contaminants but the removal rate was decreased by the presence of benzene. Organic matter also reduced the TCP degradation rate and the removal efficiency was only 8.3% in 24 h. In the field test, as the solution was injected, the oxidation reaction occurred immediately, accompanied by a sharp increase of oxidation–reduction potential (ORP) and a decrease in pH. Though the concentration of pollutants increased due to the dissolution of non-aqueous phase liquid (NAPL) at the initial stage, BTEX could still be effectively degraded in subsequent time by persulfate in both aquifers, and their removal efficiency approached 100%. However, chlorinated hydrocarbon was relatively difficult to degrade, especially TCP, which had a relatively higher initial concentration, only had a removal efficiency of 30%–45% at different aquifers and monitoring wells. These finding are important for the development of injection technology for chlorinated hydrocarbon and BTEX contaminated site remediation.

scholarly journals Aerosol optical properties in the North China Plain during HaChi campaign: an in-situ optical closure study

2011 ◽  
Vol 11 (12) ◽  
pp. 5959-5973 ◽  
Author(s):  
N. Ma ◽  
C. S. Zhao ◽  
A. Nowak ◽  
T. Müller ◽  
S. Pfeifer ◽  
...  
Keyword(s):  
Optical Properties ◽  
North China Plain ◽  
North China ◽  
Scattering Coefficient ◽  
Aerosol Optical Properties ◽  
Mean Values ◽  
The North ◽  
The North China Plain ◽  
The Mean

Abstract. The largest uncertainty in the estimation of climate forcing stems from atmospheric aerosols. In early spring and summer of 2009, two periods of in-situ measurements on aerosol physical and chemical properties were conducted within the HaChi (Haze in China) project at Wuqing, a town between Beijing and Tianjin in the North China Plain (NCP). Aerosol optical properties, including the scattering coefficient (σsp), the hemispheric back scattering coefficient (σbsp), the absorption coefficient (σap), as well as the single scattering albedo (ω), are presented. The diurnal and seasonal variations are analyzed together with meteorology and satellite data. The mean values of σsp, 550 nm of the dry aerosol in spring and summer are 280±253 and 379±251 Mm−1, respectively. The average σap for the two periods is respectively 47±38 and 43±27 Mm−1. The mean values of ω at the wavelength of 637 nm are 0.82±0.05 and 0.86±0.05 for spring and summer, respectively. The relative high levels of σsp and σbsp are representative of the regional aerosol pollution in the NCP. Pronounced diurnal cycle of $σsp, σap and ω are found, mainly influenced by the evolution of boundary layer and the accumulation of local emissions during nighttime. The pollutants transported from the southwest of the NCP are more significant than that from the two megacities, Beijing and Tianjin, in both spring and summer. An optical closure experiment is conducted to better understand the uncertainties of the measurements. Good correlations (R>0.98) are found between the values measured by the nephelometer and the values calculated with a modified Mie model. The Monte Carlo simulation shows an uncertainty of about 30 % for the calculations. Considering all possible uncertainties of measurements, calculated σsp and σbsp agree well with the measured values, indicating a stable performance of instruments and thus reliable aerosol optical data.

scholarly journals Aerosol optical properties in the North China Plain during HaChi campaign: an in-situ optical closure study

2011 ◽  
Vol 11 (3) ◽  
pp. 9567-9605 ◽  
Author(s):  
N. Ma ◽  
C. S. Zhao ◽  
A. Nowak ◽  
T. Müller ◽  
S. Pfeifer ◽  
...  
Keyword(s):  
Optical Properties ◽  
North China Plain ◽  
North China ◽  
Aerosol Optical Properties ◽  
Mean Values ◽  
The North ◽  
The North China Plain ◽  
The Mean ◽  
Local Emissions

Abstract. The largest uncertainty in the estimation of radiative forcings on climate stems from atmospheric aerosols. In winter and summer of 2009, two periods of in-situ measurements on aerosol physical and chemical properties were conducted within the HaChi project at Wuqing, a town between Beijing and Tianjin in the North China Plain (NCP). Aerosol optical properties including scattering coefficient (σsp), hemispheric back scattering coefficient (σbsp), absorption coefficient (σap, as well as single scattering albedo (ω) are presented. The characteristics of diurnal and seasonal variations are analyzed together with the meteorological and satellite data. The mean values of σsp, 550 nm of the dry aerosol in winter and summer are 280 ± 253 and 379 ± 251 Mm−1, respectively. The average σap for the two periods are respectively 47 ± 38 and 43 ± 27 Mm−1. The mean values of ω are 0.83 ± 0.05 and 0.87 ± 0.05 for winter and summer, respectively. The relative high levels of σsp and σbsp are representative of the regional polluted aerosol of the North China Plain. Pronounced diurnal cycle of σsp, σap and ω are found, mainly influenced by the evolution of boundary layer and accumulation of local emissions during night-time. Regional transport of pollutants from southwest in the NCP is significant both in winter and summer, while high values of σsp and σap correlate with calm winds in winter, which indicating the significant contribution of local emissions. An optical closure experiment is conducted to better understand uncertainties of the measurements. Good correlations (R>0.98) are found between values measured by nephelometer and values calculated with a modified Mie model. Monte Carlo simulations show an uncertainty of about 30% for the calculations. Considering all possible uncertainties of measurements, calculated σsp and σbsp agree well with measured values, indicating a stable performance of instruments and thus a reliable aerosol optical data.

Can Contingent Valuation be Used to Measure the in Situ Value of Groundwater on the North China Plain?

2006 ◽  
Vol 21 (10) ◽  
pp. 1735-1749 ◽  
Author(s):  
Yongping Wei ◽  
Brian Davidson ◽  
Deli Chen ◽  
Robert White ◽  
Baoguo Li ◽  
...  
Keyword(s):  
Contingent Valuation ◽  
North China Plain ◽  
North China ◽  
The North ◽  
The North China Plain

Simulating in situ ammonia volatilization losses in the North China Plain using a dynamic soil-crop model

2016 ◽  
Vol 179 (2) ◽  
pp. 270-285 ◽  
Author(s):  
Anna Michalczyk ◽  
Kurt Christian Kersebaum ◽  
Lisa Heimann ◽  
Marco Roelcke ◽  
Qin-Ping Sun ◽  
...  
Keyword(s):  
North China Plain ◽  
North China ◽  
Ammonia Volatilization ◽  
Crop Model ◽  
The North ◽  
The North China Plain

scholarly journals Analysis of the formation of fog and haze in North China Plain (NCP)

2011 ◽  
Vol 11 (4) ◽  
pp. 11911-11937 ◽  
Author(s):  
J. Quan ◽  
Q. Zhang ◽  
H. He ◽  
J. Liu ◽  
M. Huang ◽  
...  
Keyword(s):  
North China Plain ◽  
North China ◽  
Aerosol Particles ◽  
Rapid Changes ◽  
Low Visibility ◽  
Aerosol Number Concentration ◽  
The Impact ◽  
The Relationship

Abstract. North China Plain (NCP) is one of the most populated and polluted regions in China. During the recent years, haze and fog occur frequently and cause severely low visibility in this region. In order to better understand the impact of aerosol particles on the formation of haze and fog, a long-term record of haze and fog occurrences in the past 56 years (from 1954–2009) over NCP is analyzed. The results show that there are rapid changes in the occurrences of haze and fog over NCP. The occurrences of haze and fog were low during 1970–1980, and reached a maximum during 1981–1998. After 1999, the occurrences of haze and fog slightly decreased. There was a nonlinear relationship between the occurrences of haze and fog. When the occurrence of haze was lower than 40 days yr−1, the occurrence of fog was strongly proportional to the occurrence of haze. However, when the occurrence of haze was high (larger than 75 days yr−1), the occurrence of fog was not sensitive to the occurrence of haze. In order to better understand the relationship between the occurrences of haze and fog as well as the effect of aerosol particles on the formation of haze and fog, an in-situ field experiment was conducted during a period with a mixed occurrence of haze and fog. The analysis of the experiment suggests that there were considerably high aerosol concentrations during the measurement period, with an averaged aerosol number concentration of 24 000 cm−3. The measurement also shows that a large amount of aerosol particles can act as condensation nuclei to enhance the formation of fog droplets. As a result, a large amount of fog droplets (>1000 cm−3) with small size in radius (5–6 μm) were observed during the fog period, resulting in extremely low visibility (less than 100 m).

Sign in / Sign up

Export Citation Format

Share Document