With the launch of the first civilian early-morning orbit satellite Fengyun-3E(FY-3E),higher demands are placed on the accuracy of radiative transfer simulations for hyperspectral infrared data.Therefore,several key i...With the launch of the first civilian early-morning orbit satellite Fengyun-3E(FY-3E),higher demands are placed on the accuracy of radiative transfer simulations for hyperspectral infrared data.Therefore,several key issues are investigated in the paper.First,the accuracy of the fast atmospheric transmittance model implemented in the Advanced Research and Modeling System(ARMS)has been evaluated with both the line-by-line radiative transfer model(LBLRTM)and the actual satellite observations.The results indicate that the biases are generally less than 0.25 K when compared to the LBLRTM,while below 1.0 K for the majority of the channels when compared to the observations.However,during both comparisons,significant biases are observed in certain channels.The accuracy of Hyperspectral Infrared Atmospheric Sounder-II(HIRAS-II)onboard FY-3E is comparable to,and even superior to that of the Cross-track Infrared Sounder(CrIS)onboard NOAA-20.Furthermore,apodization is a crucial step in the processing of hyperspectral data in that the apodization function is utilized as the instrument channel spectral response function to produce the satellite channel-averaged transmittance.To further explore the difference between the apodized and unapodized simulations,Sinc function is adopted in the fast transmittance model.It is found that the use of Sinc function can make the simulations fit the original satellite observations better.When simulating with apodized observations,the use of Sinc function exhibits larger deviations compared to the Hamming function.Moreover,a correction module is applied to minimize the impact of Non-Local Thermodynamic Equilibrium(NLTE)in the shortwave infrared band.It is verified that the implementation of the NLTE correction model leads to a significant reduction in the bias between the simulation and observation for this band.展开更多
According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spe...According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spectral shift of the electronic absorption spectra is deduced. Furthermore, the lowest transition of p-nitroaniline (pNA) in water is investigated by time-dependent density functional theory method. In addition, the details of excited state properties of pNA are discussed. Using our novel expression of the spectral shift, the value of -0.99 eV is obtained for π→π^* transition in water, which is in good agreement with the available experimental result of -0.98 eV.展开更多
To surmount the deficiency in studying the multiple equilibrium states in the atmosphere motion with highly truncated spectral method, the trigonometric functions for describing the proto-typical 500 hPa height fields...To surmount the deficiency in studying the multiple equilibrium states in the atmosphere motion with highly truncated spectral method, the trigonometric functions for describing the proto-typical 500 hPa height fields and the outgoing long wave radiation (OLR) fields are retrieved re-spectively for the northward bias and the southward bias years of the western Pacific subtropical high with corresponding observational data and the optimum subset retrieval method for four fac-tors. Then the evolution mechanism of the western Pacific subtropical high is studied by means of multiple equilibrium state theory. The results show that the cause of inducing the abnormal location of the western Pacific subtropical high is differences in the early external thermal forcing, which evoke different waveforms in atmosphere. If the early meridional and zonal external thermal forcing differences are stronger, there are wave-mean flow and wave-wave interactions between the response waveforms in atmosphere. In such a case, the western Pacific subtropical high shifts northward obviously. On the contrary, when the early meridional and zonal external thermal forcing differences are weaker, there is no wave-mean flow interaction between the response waveforms in atmosphere, and accordingly the position of the western Pacific subtropical high oscillates with the external thermal forcing oscillation, and is on the south of normal.展开更多
Based on the constrained equilibrium state theory,the nonequilibrium solvation energy is derived in the framework of the continuum model.The formula for spectral shift and vertical ionization energy are deduced for a ...Based on the constrained equilibrium state theory,the nonequilibrium solvation energy is derived in the framework of the continuum model.The formula for spectral shift and vertical ionization energy are deduced for a single sphere cavity with the point charge assumption.The new model is adopted to investigate the vertical ionization for halogen atomic and molecular anions X(X = Cl,Br,I,Cl2,Br2,I2) in aqueous solution.According to the calculation using the CCSD-t/aug-cc-pVQZ method in vacuum,our final estimated vertical ionization energies in solution are very close to the experimental observations,while the traditional nonequilibrium solvation theory overestimates these vertical ionization energies.展开更多
The multiple atmospheric equilibria are studied by using a barotropic vorticity equation with thermal forcing and dissipative effects. Different low-spectral models are used to discuss the variations of theequilibrium...The multiple atmospheric equilibria are studied by using a barotropic vorticity equation with thermal forcing and dissipative effects. Different low-spectral models are used to discuss the variations of theequilibrium states, with the results that the multiple features of equilibrium states depend heavily on thetruncations of the spectra, and the low-spectral model has obvious shortcomings in solving non-linear equations,suggesting that one has to be very Careful to employ highly truncated low-spectral model in approximating partial differential equations.展开更多
In this paper,a research on the problem of multiple solutions of the three-coefficient low-spectrum model for the quasi-geostrophic ocean current equation with forcing and dissipation terms is carried out.The state of...In this paper,a research on the problem of multiple solutions of the three-coefficient low-spectrum model for the quasi-geostrophic ocean current equation with forcing and dissipation terms is carried out.The state of the ocean current under wind conditions such as those of typhoon is discussed carefully and the rela- tions between the multiple solutions and the coefficients R and ε are analyzed.It is seen that in an approxi- mate triangular region with the Rossby-coefficient R less than 0.5,and the friction-coefficient ε less than 0.22, there exist three equifibrium solutions,among which two are stable and one is unstable.For the former,the coefficient A or B in the expansion is rather large,while for the latter,A or B is relatively small.They respectively imply how much the ocean energy is fed back from the wind stress and the solution with a large A is much more stable than that with a larger B.展开更多
基金Supported by the Startup Project of Donghai Laboratory(DH-2023QD0002)National Key Research and Development Program of China(2021YFB3900400)Hunan Provincial Natural Science Foundation of China(2021JC0009)。
文摘With the launch of the first civilian early-morning orbit satellite Fengyun-3E(FY-3E),higher demands are placed on the accuracy of radiative transfer simulations for hyperspectral infrared data.Therefore,several key issues are investigated in the paper.First,the accuracy of the fast atmospheric transmittance model implemented in the Advanced Research and Modeling System(ARMS)has been evaluated with both the line-by-line radiative transfer model(LBLRTM)and the actual satellite observations.The results indicate that the biases are generally less than 0.25 K when compared to the LBLRTM,while below 1.0 K for the majority of the channels when compared to the observations.However,during both comparisons,significant biases are observed in certain channels.The accuracy of Hyperspectral Infrared Atmospheric Sounder-II(HIRAS-II)onboard FY-3E is comparable to,and even superior to that of the Cross-track Infrared Sounder(CrIS)onboard NOAA-20.Furthermore,apodization is a crucial step in the processing of hyperspectral data in that the apodization function is utilized as the instrument channel spectral response function to produce the satellite channel-averaged transmittance.To further explore the difference between the apodized and unapodized simulations,Sinc function is adopted in the fast transmittance model.It is found that the use of Sinc function can make the simulations fit the original satellite observations better.When simulating with apodized observations,the use of Sinc function exhibits larger deviations compared to the Hamming function.Moreover,a correction module is applied to minimize the impact of Non-Local Thermodynamic Equilibrium(NLTE)in the shortwave infrared band.It is verified that the implementation of the NLTE correction model leads to a significant reduction in the bias between the simulation and observation for this band.
基金ACKNOWLEDGMENTS This work was supported Science Foundation of China by the National Natural (No.91016002).
文摘According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spectral shift of the electronic absorption spectra is deduced. Furthermore, the lowest transition of p-nitroaniline (pNA) in water is investigated by time-dependent density functional theory method. In addition, the details of excited state properties of pNA are discussed. Using our novel expression of the spectral shift, the value of -0.99 eV is obtained for π→π^* transition in water, which is in good agreement with the available experimental result of -0.98 eV.
基金This work was supported by the National Key Program for Developing Basic Research (Grant No. 1998040900) and the National Natural Science Foundation of China (Grant No. D49965001).
文摘To surmount the deficiency in studying the multiple equilibrium states in the atmosphere motion with highly truncated spectral method, the trigonometric functions for describing the proto-typical 500 hPa height fields and the outgoing long wave radiation (OLR) fields are retrieved re-spectively for the northward bias and the southward bias years of the western Pacific subtropical high with corresponding observational data and the optimum subset retrieval method for four fac-tors. Then the evolution mechanism of the western Pacific subtropical high is studied by means of multiple equilibrium state theory. The results show that the cause of inducing the abnormal location of the western Pacific subtropical high is differences in the early external thermal forcing, which evoke different waveforms in atmosphere. If the early meridional and zonal external thermal forcing differences are stronger, there are wave-mean flow and wave-wave interactions between the response waveforms in atmosphere. In such a case, the western Pacific subtropical high shifts northward obviously. On the contrary, when the early meridional and zonal external thermal forcing differences are weaker, there is no wave-mean flow interaction between the response waveforms in atmosphere, and accordingly the position of the western Pacific subtropical high oscillates with the external thermal forcing oscillation, and is on the south of normal.
基金supported by the National Natural Science Foundation of China (20873087 and 20903067)
文摘Based on the constrained equilibrium state theory,the nonequilibrium solvation energy is derived in the framework of the continuum model.The formula for spectral shift and vertical ionization energy are deduced for a single sphere cavity with the point charge assumption.The new model is adopted to investigate the vertical ionization for halogen atomic and molecular anions X(X = Cl,Br,I,Cl2,Br2,I2) in aqueous solution.According to the calculation using the CCSD-t/aug-cc-pVQZ method in vacuum,our final estimated vertical ionization energies in solution are very close to the experimental observations,while the traditional nonequilibrium solvation theory overestimates these vertical ionization energies.
文摘The multiple atmospheric equilibria are studied by using a barotropic vorticity equation with thermal forcing and dissipative effects. Different low-spectral models are used to discuss the variations of theequilibrium states, with the results that the multiple features of equilibrium states depend heavily on thetruncations of the spectra, and the low-spectral model has obvious shortcomings in solving non-linear equations,suggesting that one has to be very Careful to employ highly truncated low-spectral model in approximating partial differential equations.
基金The project partly supported by the national project of 75-76-01-03“Study on numerical prediction of the South China Sea current”
文摘In this paper,a research on the problem of multiple solutions of the three-coefficient low-spectrum model for the quasi-geostrophic ocean current equation with forcing and dissipation terms is carried out.The state of the ocean current under wind conditions such as those of typhoon is discussed carefully and the rela- tions between the multiple solutions and the coefficients R and ε are analyzed.It is seen that in an approxi- mate triangular region with the Rossby-coefficient R less than 0.5,and the friction-coefficient ε less than 0.22, there exist three equifibrium solutions,among which two are stable and one is unstable.For the former,the coefficient A or B in the expansion is rather large,while for the latter,A or B is relatively small.They respectively imply how much the ocean energy is fed back from the wind stress and the solution with a large A is much more stable than that with a larger B.