scholarly journals Studies on the Climate Effects of Black Carbon Aerosols in China and Their Sensitivity to Particle Size and Optical Parameters

2018 ◽  
Vol 2018 ◽  
pp. 1-16 ◽  
Author(s):  
Xingxing Ma ◽  
Hongnian Liu ◽  
Xueyuan Wang ◽  
Zhen Peng
Keyword(s):  
Particle Size ◽  
South China ◽  
Radiative Forcing ◽  
North China ◽  
Central China ◽  
East China ◽  
Optical Parameters ◽  
Climate Effects ◽  
Clear Sky ◽  
Bc Aerosols

In this paper, based on the principle of Mie scattering, we calculated the optical parameters of BC aerosols at different scales and then applied the new optical parameters to simulate the BC aerosols concentration distribution, radiative forcing, and their climate effects. We also compared the results of optical parameters of BC aerosols with homogeneous scales and analyzed the effect on climate. Compared with the conventional uniform-scheme optical parameterization, the concentrations of the first mode of BC aerosols simulated with the optical parameters that were recalculated based on the particle size are significantly higher, while the concentrations of the other modes and the total of BC aerosols are lower. In the respective of statistics, the changes of column burdens of BC in four modes are 0.085, −0.095, −0.089, −0.054 mg/m2. The clear-sky TRF of BC are weakened in the value of 0.03 W/m2 averaged over the domain, while the all-sky TRF of BC are enhanced of  0.06 W/m2 in general. The warming effect of BC becomes weaker when using the new scheme by −0.04 K to −0.24 K. When using the new optical parameters scheme, the regional average surface concentrations of BC in four modes are 0.372, 0.264, 0.055 and 0.004 μg/m3, respectively. Especially, the first and the second mode account for as large as 53% and 38%. The surface concentration and column burden of total BC are 0.69 μg/m3 and 0.28 mg/m2 can be dropped. The regional average direct RFs of BC at the top of the atmosphere are 0.49 W/m2 under clear-sky and 0.36 W/m2 under all-sky averaged over the domain. Over most areas of central China, North China, and East China, BC may increase the temperature in a range of 0.05∼0.15 K, while over South China, BC shows cooling effect. In average, the precipitation variations caused by BC over East China, North China, South China, and Northeast China are −0.83, −0.05, −0.11, and −0.13 mm/d, respectively. As a whole, the variations of circulation, pressure, and temperature show a good correspondence.

scholarly journals Column aerosol optical properties and aerosol radiative forcing during a serious haze-fog month over North China Plain in 2013 based on ground-based sunphotometer measurements

2013 ◽  
Vol 13 (11) ◽  
pp. 29685-29720 ◽  
Author(s):  
H. Che ◽  
X. Xia ◽  
J. Zhu ◽  
Z. Li ◽  
O. Dubovic ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
North China Plain ◽  
North China ◽  
Optical Parameters ◽  
Aerosol Radiative Forcing ◽  
Coarse Mode ◽  
Fine Mode ◽  
Rural Sites ◽  
Urban Sites ◽  
Aerosol Radiative

Abstract. In January 2013, North China Plain experienced several serious haze events. Cimel sunphotometer measurements at seven sites over rural, suburban and urban regions of North China Plain from 1 to 30 January 2013 were used to further our understanding of spatial-temporal variation of aerosol optical parameters and aerosol radiative forcing (ARF). It was found that Aerosol Optical Depth at 500 nm (AOD500 nm) during non-pollution periods at all stations was lower than 0.30 and increased significantly to greater than 1.00 as pollution events developed. The Angstrom exponent (Alpha) was larger than 0.80 for all stations most of the time. AOD500 nm averages increased from north to south during both polluted and non-polluted periods on the three urban sites in Beijing. The fine mode AOD during pollution periods is about a factor of 2.5 times larger than that during the non-pollution period at urban sites but a factor of 5.0 at suburban and rural sites. The fine mode fraction of AOD675 nm was higher than 80% for all sites during January 2013. The absorption AOD675 nm at rural sites was only about 0.01 during pollution periods, while ~0.03–0.07 and 0.01–0.03 during pollution and non-pollution periods at other sites, respectively. Single scattering albedo varied between 0.87 and 0.95 during January 2013 over North China Plain. The size distribution showed an obvious tri-peak pattern during the most serious period. The fine mode effective radius in the pollution period was about 0.01–0.08 μm larger than during non-pollution periods, while the coarse mode radius in pollution periods was about 0.06–0.38 μm less than that during non-pollution periods. The total, fine and coarse mode particle volumes varied by about 0.06–0.34 μm3, 0.03–0.23 μm3, and 0.03–0.10 μm3, respectively, throughout January 2013. During the most intense period (1–16 January), aerosol radiative forcing (ARF) at the surface exceeded −50 W m−2, −180 W m−2, and −200 W m−2 at rural, suburban, and urban sites, respectively. The ARF readings at the top of the atmosphere were approximately −30 W m−2 in rural and −40–60 W m−2 in urban areas. Positive ARF at the top of the atmosphere at the Huimin suburban site was found to be different from others as a result of the high surface albedo due to snow cover.

scholarly journals Evaluation and Prediction of Wind Power Utilization Efficiency Based on Super-SBM and LSTM Models: A Case Study of 30 Provinces in China

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Chengyu Li ◽  
Qunwei Wang ◽  
Peng Zhou
Keyword(s):  
Wind Energy ◽  
Wind Power ◽  
South China ◽  
Regional Differences ◽  
Development Trend ◽  
Energy Resources ◽  
Utilization Efficiency ◽  
Central China ◽  
East China ◽  
Wind Energy Resources

Although China’s wind industry has made great progress in recent years, the wind abandonment phenomenon caused by the unbalanced development of regional wind power is still prominent. It is particularly important for the scientific development of wind power to accurately measure the utilization efficiency of wind power and understand its regional differences in China. This study establishes the improved super-efficiency slack-based measure (Super-SBM) model and long short-term memory (LSTM) network models, systematically and comprehensively measures and predicts the wind power utilization efficiency of 30 regions in China from 2013 to 2020, and explores regional differences in wind power utilization efficiency. Our results show the following: (1) China’s overall wind power utilization efficiency is relatively low but has been on a steady upward trend since 2013. (2) Regional differences are obvious, showing that the spatial distribution pattern of wind power utilization efficiency is greatest in Northeast China, followed by North China, East China, South China, Northwest China, and Central China. The “Three-North” region with abundant wind energy resources has relatively high wind power utilization efficiency and exhibits a good development trend. East China, South China, and Central China, where wind energy resources are relatively poor, have low wind power utilization efficiency, and their development trends are not stable and are more prone to change. (3) The utilization efficiency of wind power in coastal areas is generally better than that in inland areas. There are also differences among the thirty Chinese regions studied. Inner Mongolia and Shandong have achieved real efficiency in wind power utilization efficiency, with optimal allocation of input and output, and a good development trend. The other 28 regions have varying degrees of inefficiency, and there is still room for improvement.

Exploration of AGC Control Mode for North China-Central China-East China UHV Synchronous Power Grid

2013 ◽  
Vol 433-435 ◽  
pp. 1230-1236
Author(s):  
Jing Zhou ◽  
Ke Wang ◽  
Ya Ping Li ◽  
Dan Zeng
Keyword(s):  
North China ◽  
Frequency Control ◽  
Power Grid ◽  
Control Model ◽  
Active Power ◽  
Central China ◽  
Control Mode ◽  
East China ◽  
Centralized Control ◽  
The Future

With the continuous construction of ultra high voltage (UHV) power grid, East China-Central China North China will be interconnected via UHV lines to be a UHV synchronous grid in the future. Further expansion of the grid scale, the existing active power and frequency control mode has been unable to adapt to the new features. Based on the future structure of North China-Central China-East China synchronized power grid, the article built the whole network of the AGC control model using PSD-FDS full dynamic simulation program. By the simulation of examples, the problems of AGC control mode for UHV synchronous power grid has been pointed out visually. Finally, the paper presented an ideal AGC control mode called centralized control mode to deal with the new challenge.

scholarly journals Column aerosol optical properties and aerosol radiative forcing during a serious haze-fog month over North China Plain in 2013 based on ground-based sunphotometer measurements

2014 ◽  
Vol 14 (4) ◽  
pp. 2125-2138 ◽  
Author(s):  
H. Che ◽  
X. Xia ◽  
J. Zhu ◽  
Z. Li ◽  
O. Dubovik ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
North China Plain ◽  
North China ◽  
Optical Parameters ◽  
Aerosol Radiative Forcing ◽  
Coarse Mode ◽  
Fine Mode ◽  
Rural Sites ◽  
Urban Sites ◽  
Aerosol Radiative

Abstract. In January 2013, North China Plain experienced several serious haze events. Cimel sunphotometer measurements at seven sites over rural, suburban and urban regions of North China Plain from 1 to 30 January 2013 were used to further our understanding of spatial-temporal variation of aerosol optical parameters and aerosol radiative forcing (ARF). It was found that Aerosol Optical Depth at 500 nm (AOD500 nm) during non-pollution periods at all stations was lower than 0.30 and increased significantly to greater than 1.00 as pollution events developed. The Angstrom exponent (Alpha) was larger than 0.80 for all stations most of the time. AOD500 nm averages increased from north to south during both polluted and non-polluted periods on the three urban sites in Beijing. The fine mode AOD during pollution periods is about a factor of 2.5 times larger than that during the non-pollution period at urban sites but a factor of 5.0 at suburban and rural sites. The fine mode fraction of AOD675 nm was higher than 80% for all sites during January 2013. The absorption AOD675 nm at rural sites was only about 0.01 during pollution periods, while ~0.03–0.07 and 0.01–0.03 during pollution and non-pollution periods at other sites, respectively. Single scattering albedo varied between 0.87 and 0.95 during January 2013 over North China Plain. The size distribution showed an obvious tri-peak pattern during the most serious period. The fine mode effective radius in the pollution period was about 0.01–0.08 μm larger than during non-pollution periods, while the coarse mode radius in pollution periods was about 0.06–0.38 μm less than that during non-pollution periods. The total, fine and coarse mode particle volumes varied by about 0.06–0.34 μm3, 0.03–0.23 μm3, and 0.03–0.10 μm3, respectively, throughout January 2013. During the most intense period (1–16 January), ARF at the surface exceeded −50 W m−2, −180 W m−2, and −200 W m−2 at rural, suburban, and urban sites, respectively. The ARF readings at the top of the atmosphere were approximately −30 W m−2 in rural and −40–60 W m−2 in urban areas. Positive ARF at the top of the atmosphere at the Huimin suburban site was found to be different from others as a result of the high surface albedo due to snow cover.

scholarly journals Diverse response of surface ozone to COVID-19 lockdown in China

2021 ◽  
Author(s):  
Yiming Liu ◽  
Tao Wang ◽  
Trissevgeni Stavrakou ◽  
Nellie Elguindi ◽  
Thierno Doumbia ◽  
...  
Keyword(s):  
South China ◽  
Emission Reduction ◽  
North China ◽  
Surface Ozone ◽  
Cloud Fraction ◽  
Central China ◽  
Lower Atmosphere ◽  
Boundary Layer Height ◽  
Volatile Organic ◽  
Complex Dependence

<p>Ozone (O<sub>3</sub>) is a key oxidant and pollutant in the lower atmosphere. Significant increases in surface O<sub>3</sub> have been reported in many cities during the COVID-19 lockdown. Here we conduct comprehensive observation and modeling analyses of surface O<sub>3</sub> across China for periods before and during the lockdown. We find that daytime O<sub>3</sub> decreased in the subtropical south, in contrast to increases in most other regions. Meteorological changes and emission reductions both contributed to the O<sub>3</sub> changes, with a larger impact from the former especially in central China. The southward-shifted wind with increased temperature, enhanced planetary boundary layer height, decreased cloud fraction and precipitation favored the O<sub>3</sub> increase in north and central China, while the northward-shifted wind with decreased temperature and then biogenic volatile organic compounds (VOCs) emissions, increased cloud fraction and precipitation reduced O<sub>3</sub> in south China. As for the emission reduction, the drop in nitrogen oxide (NO<sub>x</sub>) emission contributed to O<sub>3</sub> increases in populated regions, whereas the reduction in VOCs contributed to O<sub>3</sub> decreases across the country. Due to a decreasing level of NO<sub>x</sub> saturation from north to south, the emission reduction in NO<sub>x</sub> (46%) and VOC (32%) contributed to net O<sub>3</sub> increases in north China; the opposite effects of NO<sub>x</sub> decrease (49%) and VOC decrease (24%) balanced out in central China, whereas the comparable decreases (45-55%) in the two precursors contributed to net O<sub>3</sub> declines in south China. Our study highlights the complex dependence of O<sub>3</sub> on its precursors and the importance of meteorology in the short-term O<sub>3</sub> variability.</p>

Some Aspects of Chinese Religious Practices and Customs in Singapore and Malaysia

1981 ◽  
Vol 12 (1) ◽  
pp. 133-141 ◽  
Author(s):  
Tadao Sakai
Keyword(s):  
Southeast Asia ◽  
South China ◽  
Religious Beliefs ◽  
Chinese Culture ◽  
North China ◽  
The Other ◽  
Central China ◽  
Asian Context ◽  
The One ◽  
The Relationship

This paper is a summary of my recent studies on the Taoist creed and common Chinese religious beliefs, in particular the religious customs of poeh (the practice of seeking divination) and the worship of the local god of the soil. While a number of papers have been published by scholars from the Singapore-Malaysia region, their findings have been somewhat limited in scope because they were confined to the Southeast Asian context. My study will be broader in scope. It will cover the relationship between the Chinese culture of China itself and that of Southeast Asia. In other words, this paper will give (1) a comparison between the cultural styles of North China, South, and Central China, (2) a study of Chinese culture in Southeast Asia viewed as an extension of the culture of South China, especially the provinces of Fukien and Kwangtung, and (3) a summary of my research on the conflict between Chinese culture in China on the one hand and that of the Singapore-Malaysia region on the other.

scholarly journals Diurnal Evolution and Structure of Long-Lived Mesoscale Convective Vortices along the Mei-Yu Front over the East China Plains

2018 ◽  
Vol 75 (3) ◽  
pp. 1005-1025 ◽  
Author(s):  
Yuanchun Zhang ◽  
Fuqing Zhang ◽  
Christopher A. Davis ◽  
Jianhua Sun
Keyword(s):  
Radiative Forcing ◽  
Central China ◽  
East China ◽  
Maturity Stage ◽  
Mountain Ranges ◽  
Low Level ◽  
Mesoscale Convective ◽  
Upper Level ◽  
Stage 1 ◽  
Convective Vortices

Abstract The structure and diurnal evolution of long-lived, eastward-propagating mesoscale convective vortices (MCVs) along typical summertime mei-yu fronts over the east China plains are investigated through composite analysis of a 30-day semi-idealized simulation. The simulation uses lateral boundary conditions that vary only diurnally in time using analyses of recurring MCV events during 1–10 July 2007. Hence, the behavior of convection and vorticity follows a closely repeating diurnal cycle for each day during the simulation. Assisted by the eastward extension of enhanced vorticity anomalies from the Sichuan basin, the incipient MCV forms in the morning hours over the immediate lee (east) of the central China mountain ranges (stage 1). From local afternoon to early evening, as the MCV moves over the plains, convection weakens in the daytime downward branch of the mountain–plains solenoid. This allows the upper-level and lower-level portions of the vortex to partially decouple, and for convection to shift to the east-southeast side of the surface vortex (stage 2). Immediately after sunset, convection reinvigorates above the low-level MCV center as a result of moistening and destabilization from a combination of radiative forcing and an intensified low-level jet. This intensifies the MCV to maturity (stage 3). The mature MCV eventually evolves into an occluding subsynoptic cyclone with strong convection across all sectors of the low-level vorticity center during the subsequent day’s morning hours along the east China coastal plains before it moves offshore (stage 4).

Seasonal Evolution of Anomalous Rainband over East China Regulated by Sea Surface Temperature Anomalies in the Northern Hemisphere

2021 ◽  
pp. 1-44
Author(s):  
Boqi Liu ◽  
Congwen Zhu ◽  
Ning Jiang ◽  
Li Guo
Keyword(s):  
South China ◽  
North China ◽  
Sudden Change ◽  
Migration Pattern ◽  
Sea Surface ◽  
East China ◽  
Seasonal Evolution ◽  
The North ◽  
Change Pattern ◽  
Sea Surface Temperature Anomalies

AbstractSeasonal evolution of rainband over East China is evident and shows remarkable year-to-year variations. The present study identified two dominant interannual modes of the seasonal evolution of rainband over East China from 1981 to 2018: (1) the sudden change pattern, in which the anomalous rainfall changes abruptly from boreal spring to summer, especially over South China; and (2) the northward migration pattern, which shows a gradual poleward migration of the anomalous rainband over East China with the East Asian summer monsoon (EASM). Both of them are regulated by the sea surface temperature anomalies (SSTAs) in the Northern Hemisphere from spring to summer. In the sudden change pattern, the SSTAs in the Pacific modulate spring rainfall over South China via the ENSO–EASM teleconnection. By contrast, the North Atlantic SSTAs change the mid-latitude wave train and modify summer rainfall over South and North China, in conjunction with the anomalous tropical circulation due to the Indian SSTAs. In the northward migration pattern, the North Pacific SSTAs alter spring rainfall over South China by varying the low-level western North Pacific subtropical high and the zonal land–sea thermal contrast over East Asia. Afterward, the ENSO-like SSTAs induce a Pacific–Japan teleconnection and shift the anomalous rainband northward to the Yangtze-Huai River and North China in summer. The seasonal switch of the SSTAs regulating these two modes is physically linked from boreal spring to summer. This mechanism provides potential seasonal predictability of the seasonal evolution of the anomalous rainband over East China.

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