The variations of sulfate formation and optical coefficients during SO2 heterogeneous reactions on hematite surface under different SO2 concentrations were examined using in situ diffuse reflectance infrared Fourier t...The variations of sulfate formation and optical coefficients during SO2 heterogeneous reactions on hematite surface under different SO2 concentrations were examined using in situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） and ion chromatograph （IC）. Laboratory experiments revealed that within ambient SO2 of 0.51-18.6 ppmv, sulfate product, producing velocity, absorption and backward scattering coefficients showed an increasing trend with SO2 concentration. Under given SO2 concentration, the velocity of sulfate producing performed an evolution of initial increasing, midterm decreasing and final stabilizing. The reactive uptake and Brunaner-Emmett-Teller （BET） uptake coefficients of heterogeneous reactions rose with SOz and exhibited high reactivities. Considering global warming, this result is important for the knowledge of heterogeneous reactions of SO2 on mineral particle surface in the atmosphere and the assessment of their impacts on radiative forcing.展开更多
On the basis of the conceptual model,the development of wintertime stratocumulus cloud has been sim- ulated by using a planetary boundary layer/cloud physics model.The main characteristics of the cloud struc- ture and...On the basis of the conceptual model,the development of wintertime stratocumulus cloud has been sim- ulated by using a planetary boundary layer/cloud physics model.The main characteristics of the cloud struc- ture and evolution obtained from the simulation are consistent with those from observations.By analyzing the modeled results,some details of the cloud structures and microphysics processes are discussed.展开更多
A 2m^3 isothermal cloud chamber mainly for ice nucleation research is described in this paper.Its structure, attached instruments and experimental procedures are also presented.The experiments of determining the ice n...A 2m^3 isothermal cloud chamber mainly for ice nucleation research is described in this paper.Its structure, attached instruments and experimental procedures are also presented.The experiments of determining the ice nuclei effectiveness for the Agl-containing aerosols produced by three formulations have been conducted and the results have been compared with those of the CSU 960-liter isothermal cloud chamber.All experimental results show that the chamber has advantages of stable performance and reproducibility.It would be expected to become a useful experimental facility for ice nucleation research.展开更多
We introduced the two-parameter stratiform cloud model of Hu and Yan (1986) into the mesoscale model ofAnthes et al. (1987), and reprogramed the latter, then constructed a three-dimensional stratiform cloud system mod...We introduced the two-parameter stratiform cloud model of Hu and Yan (1986) into the mesoscale model ofAnthes et al. (1987), and reprogramed the latter, then constructed a three-dimensional stratiform cloud system modelwhich includes three phases of water and detailed cloud physical processes. For the stability and accuracy of calculationin a larger time step, we accepted a set of hybrid-schemes for all and the time split scheme for some of the cloud physicalprocesses, and proposed a parameterized method which calculates different types of phase change processessimultaneously, and designed the falling schemes of particles following the Lagrangian method.We used a dry model, a cumulus parameterization model, a two-phase explicit scheme model, and the model pres-ented here to simulate two low-level mesoscale vortices, compared and analysed the simulating capability of these mod-els. The results show that in simulation of the circulation structure of meso-vortex, the structure of cloud system, andsurface precipitation, the model presented here is more reasonable and closer to the observations than other models.展开更多
基金supported by the National Natural Science Foundation of China (No. 40533017, 20377008,40605001)the National Key Technology R&D Program(No. 2006BAC12B001)the State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC-KF-2006-05) of China
文摘The variations of sulfate formation and optical coefficients during SO2 heterogeneous reactions on hematite surface under different SO2 concentrations were examined using in situ diffuse reflectance infrared Fourier transform spectroscopy （DRIFTS） and ion chromatograph （IC）. Laboratory experiments revealed that within ambient SO2 of 0.51-18.6 ppmv, sulfate product, producing velocity, absorption and backward scattering coefficients showed an increasing trend with SO2 concentration. Under given SO2 concentration, the velocity of sulfate producing performed an evolution of initial increasing, midterm decreasing and final stabilizing. The reactive uptake and Brunaner-Emmett-Teller （BET） uptake coefficients of heterogeneous reactions rose with SOz and exhibited high reactivities. Considering global warming, this result is important for the knowledge of heterogeneous reactions of SO2 on mineral particle surface in the atmosphere and the assessment of their impacts on radiative forcing.
文摘On the basis of the conceptual model,the development of wintertime stratocumulus cloud has been sim- ulated by using a planetary boundary layer/cloud physics model.The main characteristics of the cloud struc- ture and evolution obtained from the simulation are consistent with those from observations.By analyzing the modeled results,some details of the cloud structures and microphysics processes are discussed.
文摘A 2m^3 isothermal cloud chamber mainly for ice nucleation research is described in this paper.Its structure, attached instruments and experimental procedures are also presented.The experiments of determining the ice nuclei effectiveness for the Agl-containing aerosols produced by three formulations have been conducted and the results have been compared with those of the CSU 960-liter isothermal cloud chamber.All experimental results show that the chamber has advantages of stable performance and reproducibility.It would be expected to become a useful experimental facility for ice nucleation research.
文摘We introduced the two-parameter stratiform cloud model of Hu and Yan (1986) into the mesoscale model ofAnthes et al. (1987), and reprogramed the latter, then constructed a three-dimensional stratiform cloud system modelwhich includes three phases of water and detailed cloud physical processes. For the stability and accuracy of calculationin a larger time step, we accepted a set of hybrid-schemes for all and the time split scheme for some of the cloud physicalprocesses, and proposed a parameterized method which calculates different types of phase change processessimultaneously, and designed the falling schemes of particles following the Lagrangian method.We used a dry model, a cumulus parameterization model, a two-phase explicit scheme model, and the model pres-ented here to simulate two low-level mesoscale vortices, compared and analysed the simulating capability of these mod-els. The results show that in simulation of the circulation structure of meso-vortex, the structure of cloud system, andsurface precipitation, the model presented here is more reasonable and closer to the observations than other models.
