A package(a tool model) for program of predicting atmospheric chemical kinetics with sensitivity analysis is presented. The new direct method of calculating the first order sensitivity coefficients using sparse matri...A package(a tool model) for program of predicting atmospheric chemical kinetics with sensitivity analysis is presented. The new direct method of calculating the first order sensitivity coefficients using sparse matrix technology to chemical kinetics is included in the tool model, it is only necessary to triangularize the matrix related to the Jacobian matrix of the model equation. The Gear type procedure is used to integrate a model equation and its coupled auxiliary sensitivity coefficient equations. The FORTRAN subroutines of the model equation, the sensitivity coefficient equations, and their Jacobian analytical expressions are generated automatically from a chemical mechanism. The kinetic representation for the model equation and its sensitivity coefficient equations, and their Jacobian matrix is presented. Various FORTRAN subroutines in packages, such as SLODE, modified MA28, Gear package, with which the program runs in conjunction are recommended. The photo\|oxidation of dimethyl disulfide is used for illustration.展开更多
The comparison of five atmospheric chemical modeling schemes was presented from accuracy,efficiency and progamming in term of Carbon bond Mechanism IV of atmospheric chemical reactions. The major results were as fo...The comparison of five atmospheric chemical modeling schemes was presented from accuracy,efficiency and progamming in term of Carbon bond Mechanism IV of atmospheric chemical reactions. The major results were as follows. The classical Gear scheme can provide an accurate solution and it is easy for programming by a computer automatically. The sparse matrix Gear type scheme can also provide an accurate solution but much faster than classical Gear scheme. QSSA,EBI and hybrid schemes can run with much longer time step without sacrificing of accuracy, therefore, much efficiently. If analytical solution is obtained by EBI scheme the accuracy and efficiency are much better.展开更多
We integrated Enviro-HIRLAM(Environment-High Resolution Limited Area Model)meteorological output into FLEXPART(FLEXible PARTicle dispersion model).A FLEXPART simulation requires meteorological input from a numerical w...We integrated Enviro-HIRLAM(Environment-High Resolution Limited Area Model)meteorological output into FLEXPART(FLEXible PARTicle dispersion model).A FLEXPART simulation requires meteorological input from a numerical weather prediction(NWP)model.The publicly available version of FLEXPART can utilize either ECMWF(European Centre for Medium-range Weather Forecasts)Integrated Forecast System(IFS)forecast or reanalysis NWP data,or NCEP(U.S.National Center for Environmental Prediction)Global Forecast System(GFS)forecast or reanalysis NWP data.The primary benefits of using Enviro-HIRLAM are that it runs at a higher resolution and accounts for aerosol effects in meteorological fields.We compared backward trajectories gener-ated with FLEXPART using Enviro-HIRLAM(both with and without aerosol effects)to trajectories generated using NCEP GFS and ECMWF IFS meteorological inputs,for a case study of a heavy haze event which occurred in Beijing,China in November 2018.We found that results from FLEXPART were considerably different when using different meteorological inputs.When aerosol effects were included in the NWP,there was a small but noticeable differ-ence in calculated trajectories.Moreover,when looking at potential emission sensitivity instead of simply expressing trajectories as lines,additional information,which may have been missed when looking only at trajectories as lines,can be inferred.展开更多
文摘A package(a tool model) for program of predicting atmospheric chemical kinetics with sensitivity analysis is presented. The new direct method of calculating the first order sensitivity coefficients using sparse matrix technology to chemical kinetics is included in the tool model, it is only necessary to triangularize the matrix related to the Jacobian matrix of the model equation. The Gear type procedure is used to integrate a model equation and its coupled auxiliary sensitivity coefficient equations. The FORTRAN subroutines of the model equation, the sensitivity coefficient equations, and their Jacobian analytical expressions are generated automatically from a chemical mechanism. The kinetic representation for the model equation and its sensitivity coefficient equations, and their Jacobian matrix is presented. Various FORTRAN subroutines in packages, such as SLODE, modified MA28, Gear package, with which the program runs in conjunction are recommended. The photo\|oxidation of dimethyl disulfide is used for illustration.
文摘The comparison of five atmospheric chemical modeling schemes was presented from accuracy,efficiency and progamming in term of Carbon bond Mechanism IV of atmospheric chemical reactions. The major results were as follows. The classical Gear scheme can provide an accurate solution and it is easy for programming by a computer automatically. The sparse matrix Gear type scheme can also provide an accurate solution but much faster than classical Gear scheme. QSSA,EBI and hybrid schemes can run with much longer time step without sacrificing of accuracy, therefore, much efficiently. If analytical solution is obtained by EBI scheme the accuracy and efficiency are much better.
基金the Jenny and Antti Wihuri Foundation project,with the grant for“Air pollution cocktail in Gigacity”Funding was also received from the Research Council of Finland(formerly the Academy of Finland,AoF)project 311932 and applied towards this project+1 种基金Partially,funding included contribution from EU Horizon 2020 CRiceS project“Climate relevant interactions and feedbacks:the key role of sea ice and snow in the polar and global climate system”under grant agreement No 101003826and AoF project ACCC“The Atmosphere and Climate Competence Center”under grant agreement No 337549.
文摘We integrated Enviro-HIRLAM(Environment-High Resolution Limited Area Model)meteorological output into FLEXPART(FLEXible PARTicle dispersion model).A FLEXPART simulation requires meteorological input from a numerical weather prediction(NWP)model.The publicly available version of FLEXPART can utilize either ECMWF(European Centre for Medium-range Weather Forecasts)Integrated Forecast System(IFS)forecast or reanalysis NWP data,or NCEP(U.S.National Center for Environmental Prediction)Global Forecast System(GFS)forecast or reanalysis NWP data.The primary benefits of using Enviro-HIRLAM are that it runs at a higher resolution and accounts for aerosol effects in meteorological fields.We compared backward trajectories gener-ated with FLEXPART using Enviro-HIRLAM(both with and without aerosol effects)to trajectories generated using NCEP GFS and ECMWF IFS meteorological inputs,for a case study of a heavy haze event which occurred in Beijing,China in November 2018.We found that results from FLEXPART were considerably different when using different meteorological inputs.When aerosol effects were included in the NWP,there was a small but noticeable differ-ence in calculated trajectories.Moreover,when looking at potential emission sensitivity instead of simply expressing trajectories as lines,additional information,which may have been missed when looking only at trajectories as lines,can be inferred.