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Fuqing Zhang - One of the best experts on this subject based on the ideXlab platform.

  • influence of monsoonal wind speed and moisture content on intensity and Diurnal Variations of the mei yu season coastal rainfall over south china
    Journal of the Atmospheric Sciences, 2017
    Co-Authors: Xingchao Chen, Fuqing Zhang, Kun Zhao
    Abstract:

    AbstractConvection-permitting numerical experiments using the Weather Research and Forecasting (WRF) Model are performed to explore the influence of monsoonal onshore wind speed and moisture content on the intensity and Diurnal Variations of coastal rainfall over south China during the mei-yu seasons. The focus of the analyses is on a pair of 10-day WRF simulations with Diurnally cyclic-in-time lateral boundary conditions averaged over the high versus low onshore wind speed days of the 2007–09 mei-yu seasons. Despite differences in the rainfall intensity, the spatial distributions and Diurnal Variations of rainfall in both simulations verified qualitatively well against the mean estimates derived from ground-based radar observations, averaged respectively over either the high-wind or low-wind days.Sensitivity experiments show that the pattern of coastal rainfall spatial distribution is mostly controlled by the ambient onshore wind speed. During the high-wind days, strong coastal rainfall is concentrated a...

  • impacts of mountain plains solenoid on Diurnal Variations of rainfalls along the mei yu front over the east china plains
    Monthly Weather Review, 2012
    Co-Authors: Jianhua Sun, Fuqing Zhang
    Abstract:

    AbstractConvection-permitting numerical experiments using the Weather Research and Forecasting (WRF) model are performed to examine the impact of a thermally driven mountain–plains solenoid (MPS) on the Diurnal Variations of precipitation and mesoscale convective vortices along the mei-yu front over the east China plains during 1–10 July 2007. The focus of the analyses is a 10-day simulation that used the 10-day average of the global analysis at 0000 UTC as the initial condition and the 10-day averages every 6 h as lateral boundary conditions (with Diurnal Variations only). Despite differences in the rainfall intensity and location, this idealized experiment successfully simulated the observed Diurnal variation and eastward propagation of rainfall and mesoscale convective vortices along the mei-yu front. It was found that the upward branch of the MPS, along with the attendant nocturnal low-level jet, is primarily responsible for the midnight-to-early-morning rainfall enhancement along the mei-yu front. Th...

  • Diurnal Variations of warm season precipitation east of the tibetan plateau over china
    Monthly Weather Review, 2011
    Co-Authors: Xinghua Bao, Fuqing Zhang, Jianhua Sun
    Abstract:

    AbstractThis study explores the Diurnal Variations of the warm-season precipitation to the east of the Tibetan Plateau over China using the high-resolution NOAA/Climate Prediction Center morphing technique (CMORPH) precipitation data and the Global Forecast System (GFS) gridded analyses during mid-May to mid-August of 2003–09. Complementary to the past studies using satellite or surface observations, it is found that there are strong Diurnal Variations in the summertime precipitation over the focus domain to the east of the Tibetan Plateau. These Diurnal precipitation cycles are strongly associated with several thermally driven regional mountain–plains solenoids due to the differential heating between the Tibetan Plateau, the highlands, the plains, and the ocean. The Diurnal cycles differ substantially from region to region and during the three different month-long periods: the pre-mei-yu period (15 May–15 June), the mei-yu period (15 June–15 July), and the post-mei-yu period (15 July–15 August).In partic...

  • Diurnal Variations of warm season precipitation over northern china
    Monthly Weather Review, 2010
    Co-Authors: Fuqing Zhang
    Abstract:

    Abstract This study examines the Diurnal Variations of the warm-season precipitation over northern China using the high-resolution precipitation products obtained from the Climate Prediction Center’s morphing technique (CMORPH) during May–August of 2003–09. The areas of focus are the Yanshan–Taihangshan Mountain ranges along the east peripheries of the Loess and Inner Mongolian Plateaus and the adjacent North China Plains. It is found that the averaged peak in local precipitation begins early in the afternoon near the top of the mountain ranges and propagates downslope and southeastward at a speed of ∼13 m s−1. The peak reaches the central North China Plains around midnight and the early morning hours resulting in a broad area of nocturnal precipitation maxima over the plains. The Diurnal precipitation peak (minimum) is closely collocated with the upward (downward) branch of a mountain–plains solenoid (MPS) circulation. Both the MPS and a low-level southwesterly nocturnal jet are likely to be jointly resp...

Jianhua Sun - One of the best experts on this subject based on the ideXlab platform.

  • impacts of mountain plains solenoid on Diurnal Variations of rainfalls along the mei yu front over the east china plains
    Monthly Weather Review, 2012
    Co-Authors: Jianhua Sun, Fuqing Zhang
    Abstract:

    AbstractConvection-permitting numerical experiments using the Weather Research and Forecasting (WRF) model are performed to examine the impact of a thermally driven mountain–plains solenoid (MPS) on the Diurnal Variations of precipitation and mesoscale convective vortices along the mei-yu front over the east China plains during 1–10 July 2007. The focus of the analyses is a 10-day simulation that used the 10-day average of the global analysis at 0000 UTC as the initial condition and the 10-day averages every 6 h as lateral boundary conditions (with Diurnal Variations only). Despite differences in the rainfall intensity and location, this idealized experiment successfully simulated the observed Diurnal variation and eastward propagation of rainfall and mesoscale convective vortices along the mei-yu front. It was found that the upward branch of the MPS, along with the attendant nocturnal low-level jet, is primarily responsible for the midnight-to-early-morning rainfall enhancement along the mei-yu front. Th...

  • Diurnal Variations of warm season precipitation east of the tibetan plateau over china
    Monthly Weather Review, 2011
    Co-Authors: Xinghua Bao, Fuqing Zhang, Jianhua Sun
    Abstract:

    AbstractThis study explores the Diurnal Variations of the warm-season precipitation to the east of the Tibetan Plateau over China using the high-resolution NOAA/Climate Prediction Center morphing technique (CMORPH) precipitation data and the Global Forecast System (GFS) gridded analyses during mid-May to mid-August of 2003–09. Complementary to the past studies using satellite or surface observations, it is found that there are strong Diurnal Variations in the summertime precipitation over the focus domain to the east of the Tibetan Plateau. These Diurnal precipitation cycles are strongly associated with several thermally driven regional mountain–plains solenoids due to the differential heating between the Tibetan Plateau, the highlands, the plains, and the ocean. The Diurnal cycles differ substantially from region to region and during the three different month-long periods: the pre-mei-yu period (15 May–15 June), the mei-yu period (15 June–15 July), and the post-mei-yu period (15 July–15 August).In partic...

Chunsheng Zhao - One of the best experts on this subject based on the ideXlab platform.

  • Diurnal Variations of aerosol optical properties in the north china plain and their influences on the estimates of direct aerosol radiative effect
    Atmospheric Chemistry and Physics, 2015
    Co-Authors: Ye Kuang, Chunsheng Zhao
    Abstract:

    Abstract. In this paper, the Diurnal Variations of aerosol optical properties and their influences on the estimation of daily average direct aerosol radiative effect (DARE) in the North China Plain (NCP) are investigated based on in situ measurements from Haze in China campaign. For ambient aerosol, the Diurnal patterns of single scattering albedo (SSA) and asymmetry factor (g) in the NCP are both highest at dawn and lowest in the late afternoon, and quite different from those of dry-state aerosol. The relative humidity (RH) is the dominant factor which determines the Diurnal pattern of SSA and g for ambient aerosol. Basing on the calculated SSA and g, several cases are designed to investigate the impacts of the Diurnal changes of aerosol optical properties on DARE. The results demonstrate that the Diurnal changes of SSA and g in the NCP have significant influences on the estimation of DARE at the top of the atmosphere (TOA). If the full temporal coverage of aerosol optical depth (AOD), SSA and g are available, an accurate estimation of daily average DARE can be achieved by using the daily averages of AOD, SSA and g. However, due to the lack of full temporal coverage data sets of SSA and g, their daily averages are usually not available. Basing on the results of designed cases, if the RH plays a dominant role in the Diurnal Variations of SSA and g, we suggest that using both SSA and g averaged over early morning and late afternoon as inputs for radiative transfer model to improve the accurate estimation of DARE. If the temporal samplings of SSA or g are too few to adopt this method, either averaged over early morning or late afternoon of both SSA and g can be used to improve the estimation of DARE at the TOA.

  • hygroscopic properties of aerosol particles at high relative humidity and their Diurnal Variations in the north china plain
    Atmospheric Chemistry and Physics, 2011
    Co-Authors: Chunsheng Zhao, T Gobel, E Hallbauer, A Nowak, Wanyun Xu, Z Z Deng, K Mildenberger, S Henning, F Stratmann, A Wiedensohler
    Abstract:

    The hygroscopic properties of submicron aerosol particles were determined at a suburban site (Wuqing) in the North China Plain among a cluster of cities during the period 17 July to 12 August, 2009. A High Humidity Tandem Dif- ferential Mobility Analyser (HH-TDMA) instrument was ap- plied to measure the hygroscopic growth factor (GF) at 90%, 95% and 98.5% relative humidity (RH) for particles with dry diameters between 50 and 250 nm. The probability distribu- tion of GF (GF-PDF) averaged over the period shows a dis- tinct bimodal pattern, namely, a dominant more-hygroscopic (MH) group and a smaller nearly-hydrophobic (NH) group. The MH group particles were highly hygroscopic, and their GF was relatively constant during the period with average values of 1.54± 0.02, 1.81± 0.04 and 2.45± 0.07 at 90%, 95% and 98.5% RH (D0 = 100 nm), respectively. The NH group particles grew very slightly when exposed to high RH, with GF values of 1.08± 0.02, 1.13± 0.06 and 1.24± 0.13 respectively at 90%, 95% and 98.5% RH (D0 = 100 nm). The hygroscopic growth behaviours at different RHs were well represented by a single-parameter K ¨ ohler model. Thus, the calculation of GF as a function of RH and dry diameter could be facilitated by an empirical parameterization of as function of dry diameter. A strong Diurnal pattern in number fraction of different hygroscopic groups was observed. The average number fraction of NH particles during the day was about 8%, while during the nighttime fractions up to 20% were reached. Correspondingly, the state of mixing in terms of water uptake varied significantly during a day. Simula- tions using a particle-resolved aerosol box model (PartMC- MOSAIC) suggest that the Diurnal Variations of aerosol hy- groscopicity and mixing state were mainly caused by the evo- lution of the atmospheric mixing layer. The shallow noctur- nal boundary layer during the night facilitated the accumu-

  • hygroscopic properties of aerosol particles at high relative humidity and their Diurnal Variations in the north china plain
    Atmospheric Chemistry and Physics, 2011
    Co-Authors: Pengfei Liu, Chunsheng Zhao, T Gobel, E Hallbauer, A Nowak, K Mildenberger, S Henning, Liang Ran, Zhaoze Deng, F Stratmann
    Abstract:

    Abstract. The hygroscopic properties of submicron aerosol particles were determined at a suburban site (Wuqing) in the North China Plain among a cluster of cities during the period 17 July to 12 August, 2009. A High Humidity Tandem Differential Mobility Analyser (HH-TDMA) instrument was applied to measure the hygroscopic growth factor (GF) at 90%, 95% and 98.5% relative humidity (RH) for particles with dry diameters between 50 and 250 nm. The probability distribution of GF (GF-PDF) averaged over the period shows a distinct bimodal pattern, namely, a dominant more-hygroscopic (MH) group and a smaller nearly-hydrophobic (NH) group. The MH group particles were highly hygroscopic, and their GF was relatively constant during the period with average values of 1.54 ± 0.02, 1.81 ± 0.04 and 2.45 ± 0.07 at 90%, 95% and 98.5% RH (D0 = 100 nm), respectively. The NH group particles grew very slightly when exposed to high RH, with GF values of 1.08 ± 0.02, 1.13 ± 0.06 and 1.24 ± 0.13 respectively at 90%, 95% and 98.5% RH (D0 = 100 nm). The hygroscopic growth behaviours at different RHs were well represented by a single-parameter Kohler model. Thus, the calculation of GF as a function of RH and dry diameter could be facilitated by an empirical parameterization of κ as function of dry diameter. A strong Diurnal pattern in number fraction of different hygroscopic groups was observed. The average number fraction of NH particles during the day was about 8%, while during the nighttime fractions up to 20% were reached. Correspondingly, the state of mixing in terms of water uptake varied significantly during a day. Simulations using a particle-resolved aerosol box model (PartMC-MOSAIC) suggest that the Diurnal Variations of aerosol hygroscopicity and mixing state were mainly caused by the evolution of the atmospheric mixing layer. The shallow nocturnal boundary layer during the night facilitated the accumulation of freshly emitted carbonaceous particles (mainly hydrophobic) near the surface while in the morning turbulence entrained the more aged and more hygroscopic particles from aloft and diluted the NH particles near the surface resulting in a decrease in the fraction of NH particles.

F Stratmann - One of the best experts on this subject based on the ideXlab platform.

  • hygroscopic properties of aerosol particles at high relative humidity and their Diurnal Variations in the north china plain
    Atmospheric Chemistry and Physics, 2011
    Co-Authors: Chunsheng Zhao, T Gobel, E Hallbauer, A Nowak, Wanyun Xu, Z Z Deng, K Mildenberger, S Henning, F Stratmann, A Wiedensohler
    Abstract:

    The hygroscopic properties of submicron aerosol particles were determined at a suburban site (Wuqing) in the North China Plain among a cluster of cities during the period 17 July to 12 August, 2009. A High Humidity Tandem Dif- ferential Mobility Analyser (HH-TDMA) instrument was ap- plied to measure the hygroscopic growth factor (GF) at 90%, 95% and 98.5% relative humidity (RH) for particles with dry diameters between 50 and 250 nm. The probability distribu- tion of GF (GF-PDF) averaged over the period shows a dis- tinct bimodal pattern, namely, a dominant more-hygroscopic (MH) group and a smaller nearly-hydrophobic (NH) group. The MH group particles were highly hygroscopic, and their GF was relatively constant during the period with average values of 1.54± 0.02, 1.81± 0.04 and 2.45± 0.07 at 90%, 95% and 98.5% RH (D0 = 100 nm), respectively. The NH group particles grew very slightly when exposed to high RH, with GF values of 1.08± 0.02, 1.13± 0.06 and 1.24± 0.13 respectively at 90%, 95% and 98.5% RH (D0 = 100 nm). The hygroscopic growth behaviours at different RHs were well represented by a single-parameter K ¨ ohler model. Thus, the calculation of GF as a function of RH and dry diameter could be facilitated by an empirical parameterization of as function of dry diameter. A strong Diurnal pattern in number fraction of different hygroscopic groups was observed. The average number fraction of NH particles during the day was about 8%, while during the nighttime fractions up to 20% were reached. Correspondingly, the state of mixing in terms of water uptake varied significantly during a day. Simula- tions using a particle-resolved aerosol box model (PartMC- MOSAIC) suggest that the Diurnal Variations of aerosol hy- groscopicity and mixing state were mainly caused by the evo- lution of the atmospheric mixing layer. The shallow noctur- nal boundary layer during the night facilitated the accumu-

  • hygroscopic properties of aerosol particles at high relative humidity and their Diurnal Variations in the north china plain
    Atmospheric Chemistry and Physics, 2011
    Co-Authors: Pengfei Liu, Chunsheng Zhao, T Gobel, E Hallbauer, A Nowak, K Mildenberger, S Henning, Liang Ran, Zhaoze Deng, F Stratmann
    Abstract:

    Abstract. The hygroscopic properties of submicron aerosol particles were determined at a suburban site (Wuqing) in the North China Plain among a cluster of cities during the period 17 July to 12 August, 2009. A High Humidity Tandem Differential Mobility Analyser (HH-TDMA) instrument was applied to measure the hygroscopic growth factor (GF) at 90%, 95% and 98.5% relative humidity (RH) for particles with dry diameters between 50 and 250 nm. The probability distribution of GF (GF-PDF) averaged over the period shows a distinct bimodal pattern, namely, a dominant more-hygroscopic (MH) group and a smaller nearly-hydrophobic (NH) group. The MH group particles were highly hygroscopic, and their GF was relatively constant during the period with average values of 1.54 ± 0.02, 1.81 ± 0.04 and 2.45 ± 0.07 at 90%, 95% and 98.5% RH (D0 = 100 nm), respectively. The NH group particles grew very slightly when exposed to high RH, with GF values of 1.08 ± 0.02, 1.13 ± 0.06 and 1.24 ± 0.13 respectively at 90%, 95% and 98.5% RH (D0 = 100 nm). The hygroscopic growth behaviours at different RHs were well represented by a single-parameter Kohler model. Thus, the calculation of GF as a function of RH and dry diameter could be facilitated by an empirical parameterization of κ as function of dry diameter. A strong Diurnal pattern in number fraction of different hygroscopic groups was observed. The average number fraction of NH particles during the day was about 8%, while during the nighttime fractions up to 20% were reached. Correspondingly, the state of mixing in terms of water uptake varied significantly during a day. Simulations using a particle-resolved aerosol box model (PartMC-MOSAIC) suggest that the Diurnal Variations of aerosol hygroscopicity and mixing state were mainly caused by the evolution of the atmospheric mixing layer. The shallow nocturnal boundary layer during the night facilitated the accumulation of freshly emitted carbonaceous particles (mainly hydrophobic) near the surface while in the morning turbulence entrained the more aged and more hygroscopic particles from aloft and diluted the NH particles near the surface resulting in a decrease in the fraction of NH particles.

Gabriele E. Schaumann - One of the best experts on this subject based on the ideXlab platform.

  • Diurnal Variations of air soil exchange of semivolatile organic compounds pahs pcbs ocps and pbdes in a central european receptor area
    Environmental Science & Technology, 2016
    Co-Authors: Céline Degrendele, Ondřej Audy, Jakub Hofman, Marie D. Mulder, Jiři Kucerik, Petr Kukucka, Petra Přibylova, Roman Prokes, Milan Saňka, Gabriele E. Schaumann
    Abstract:

    Concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) in air and soil, their fugacities, and the experimental soil-air partitioning coefficient (KSA) were determined at two background sites in the Gt. Hungarian Plain in August 2013. The concentrations of the semivolatile organic compounds (SOCs) in the soil were not correlated with the organic carbon content but with two indirect parameters of mineralization and aromaticity, suggesting that soil organic matter quality is an important parameter affecting the sorption of SOCs onto soils. Predictions based on the assumption that absorption is the dominant process were in good agreement with the measurements for PAHs, OCPs, and the low chlorinated PCBs. In general, soils were found to be a source of PAHs, high chlorinated PCBs, the majority of OCPs and PBDEs, and a sink for the low chlorinated PCBs and γ-hexachlorocyclohexane. Diurnal Variations...

  • Diurnal Variations of Air-Soil Exchange of Semivolatile Organic Compounds (PAHs, PCBs, OCPs, and PBDEs) in a Central European Receptor Area
    2016
    Co-Authors: Céline Degrendele, Ondřej Audy, Jakub Hofman, Jiři Kučerik, Petr Kukučka, Marie D. Mulder, Petra Přibylová, Roman Prokeš, Milan Šáňka, Gabriele E. Schaumann
    Abstract:

    Concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) in air and soil, their fugacities, and the experimental soil-air partitioning coefficient (KSA) were determined at two background sites in the Gt. Hungarian Plain in August 2013. The concentrations of the semivolatile organic compounds (SOCs) in the soil were not correlated with the organic carbon content but with two indirect parameters of mineralization and aromaticity, suggesting that soil organic matter quality is an important parameter affecting the sorption of SOCs onto soils. Predictions based on the assumption that absorption is the dominant process were in good agreement with the measurements for PAHs, OCPs, and the low chlorinated PCBs. In general, soils were found to be a source of PAHs, high chlorinated PCBs, the majority of OCPs and PBDEs, and a sink for the low chlorinated PCBs and γ-hexachlorocyclohexane. Diurnal Variations in the direction of the soil-air exchange were found for two compounds (i.e., pentachlorobenzene and p,p′-dichlorodiphenyldichloroethane), with volatilization during the day and deposition in the night. The concentrations of most SOCs in the near-ground atmosphere were dominated by revolatilization from the soil