Improved particulate matter simulation method based on high-resolution earth system mode

Abstract

The invention provides a particulate matter simulation improvement method based on a high-resolution earth system mode, which is characterized in that an aerosol thermodynamic model is coupled in an original aerosol module based on the high-resolution earth system mode so as to realize simulation of nitrate aerosol and the like. The nitric acid gas mass transfer coefficient calculation parameters are adjusted, the nitrate aerosol simulation deviation is reduced, and the particulate matter concentration simulation capacity is improved. By adding an aerosol thermodynamic model in an earth system mode in a coupling manner, a mode aerosol physical and chemical mechanism is enriched, simulation of nitrate aerosol is realized, and an important tool is provided for researching global aerosol distribution, change and environmental effect. Based on a high-resolution earth system mode, the aerosol simulation capability of the mode is improved, the mode simulation deviation is reduced, and the reliability of atmospheric pollution prediction is enhanced. And according to the absorption coefficient difference of the nitric acid gas in the mineral dust, adjusting the mass transfer coefficient of the nitric acid gas relative to dust particles, and correcting the underestimation of the mode to the nitrate aerosol.

Description

Technical Field

[0001] The present invention relates to the field of high performance computing technology, and in particular to an improved method for simulating particle matter based on a high-resolution earth system model. Background Art

[0002] With the development of supercomputers, simulation of high-resolution Earth system models has become possible. Recently, based on the domestic multi-core heterogeneous supercomputer platform, we have achieved stable operation of high-resolution (based on the common Earth system model CESM; the atmosphere and land surface resolution is about 25 kilometers) Earth system model atmospheric chemistry simulation, and improved the simulation accuracy of ozone (CN117669201 B). Compared with ozone, the composition and chemical mechanism of particulate matter are more complex, and the chemical mechanism of particulate matter simulation in the Earth system model is still imperfect. For example, the atmosphere module (CAM-chem) of the Earth system model has not yet considered the aerosol thermodynamic process, and it is impossible to simulate nitrate aerosols, which increases the uncertainty of aerosol concentrations and their climate effect assessments. Therefore, this patent couples the aerosol thermodynamic model in the Earth system model to improve the atmospheric chemical mechanism and enhance the aerosol simulation capability.

[0003] In addition, with the improvement of spatial resolution and the coupling of aerosol thermodynamic models, there are other problems in the model. On the one hand, the aerosol thermodynamic model realizes the gas-particle distribution process by calculating the dynamic mass transfer coefficients of meteorological species in particles of different particle size segments. 3 The gas absorption coefficient on the surface of dust particles is much lower than that of other particles and is treated specially. However, the absorption coefficient of nitric acid gas on dust particles is set to 1.1×10 -3 (The experimental range is 0.1×10 -3 to 0.21), the coefficient value is too low, which causes the model to underestimate the concentration level of nitrate aerosol to a certain extent. In addition, the enhanced dust emission caused by the increase in model resolution has aggravated the uncertainty of nitrate aerosol simulation. Therefore, on the basis of improving the model resolution and coupling thermodynamic model, this patent will continue to adjust the dust emission coefficient to improve the rationality of the simulation of dust emission in the high-resolution mode. Then correct the nitric acid gas absorption coefficient to optimize the nitrate aerosol simulation of the model. Summary of the invention

[0004] In order to make up for the deficiencies of the prior art, the present invention provides an improved method for simulating particulate matter and its components based on a high-resolution Earth system model. Based on the high-resolution Earth system model, an aerosol thermodynamic model is coupled to the original aerosol module to achieve the simulation of nitrate aerosols and the simulation improvement of other aerosols. The calculation parameters of the nitric acid gas mass transfer coefficient are adjusted to reduce the nitrate aerosol simulation deviation and improve the particulate matter concentration simulation capability.

[0005] The present invention is implemented by the following technical solution: an improved method for simulating particulate matter based on a high-resolution earth system model, specifically comprising the following steps: Step S1, coupling the aerosol thermodynamic model: the aerosol simulation in the Earth system model adopts the four-mode aerosol module MAM4, including four modes: Agen core membrane, accumulation mode, coarse mode and primary carbon; the aerosol thermodynamic model MOSAIC is coupled to the aerosol module MAM4, and the existing aerosol species include sulfate aerosol, black carbon aerosol, dust aerosol, sea salt aerosol, primary organic aerosol and secondary organic aerosol; on this basis, new species are added including nitrate NO 3 - 、Ammonium salt NH 4 + , sodium Na + , chlorine - Calcium 2+ 、Carbonate CO 3 2- Insert the relevant new species into the default parameter list (namelist) file, the aerosol basic parameter initial definition script (modal_aero_data.F90), the aerosol concentration calculation update file (sox_cldaero_mod.F90), and the sea salt and dust aerosol calculation scripts; Step S2, preparation of model simulation conditions: the input conditions in the model use high-resolution data, including anthropogenic emission inventory, biomass burning sources and meteorological forcing fields; the anthropogenic emission inventory uses the 0.1° Global Anthropogenic Emission Inventory (CAMS-GLOB-ANT) released by the Copernicus Monitoring Service (CAMS), the biomass burning source uses the 0.1° Fire Emissions Inventory (FINN) released by the National Center for Atmospheric Research (NCAR), and the climate forcing field uses the reanalysis data of the Global Land Actual Evapotranspiration Dataset (MERRA-2).

[0006] Step S3, dust emission flux adjustment: Dust emission is highly sensitive to model resolution. After improving the resolution, the dust emission factor needs to be used for targeted adjustment. After the adjustment, the simulated global dust aerosol optical thickness is relatively reasonable. The dust emission flux calculation formula is as follows: (1) in, cflx represents the dust emission flux, idust Indicates dust particles of a certain size range. ndust is the total number of dust particle size segments, dust_in represents the dust emission simulated by the land surface model, dust_scl is the dust emission distribution coefficient, soil_erod The soil erosion capacity, soil_erod_fact is the dust emission adjustment factor; Step S4: HNO 3 Gas key coefficient adjustment: For HNO in mode 3 The mass transfer coefficient in mineral dust is calculated as follows: (2) Absorption coefficient in mode ( γ ) is taken as 0.0011; Step S5: The model will output high-resolution aerosol, gas concentration and meteorological data of different time scales as needed. The scripts will be written based on NCL to batch process the output results and save them as NetCDF files. For aerosol species, the units need to be converted based on data including temperature and air pressure, and compared with the observed data. The scripts are designed to achieve simultaneous output and processing, and the results are saved in an external network attached storage (NAS) system. Step S6: Visualize the obtained aerosol, gas and meteorological data, and realize the visualization of the output results based on the NCL language; use the ESMF function of NCL to interpolate the output results and compare them with the observed data. The visualization scheme includes time series diagram, spatial distribution diagram and scatter diagram; Step S7, model evaluation: The meteorological observation data used for evaluation are ERA5 reanalysis data of the European Centre for Medium-Range Weather Forecasts, with a resolution of 0.25 degrees; PM 2.5 The data of the European Monitoring and Evaluation Programme (EMEP) and the Inter-agency Monitoring of the Protected Visual Environment (IMPROVE) were used for the PM 2.5 The concentration data comes from the China National Environmental Monitoring Center, and the particulate matter component data uses the China Atmospheric Composition Near-Real-Time Tracking Dataset (TAP) released by Tsinghua University. The observation results are interpolated to a 0.25 degree grid and compared with the model results and presented in graphical and tabular form.

[0007] As a preferred solution, the new species sodium Na in step S1 + , chlorine - The sum of the two aerosols represents sea salt aerosol, while dust is composed of 2% calcium Ca 2+ , 3% carbonate CO 3 2- and 95% of other inorganic substances not explicitly specified.

[0008] As a preferred solution, the dust emission adjustment factor in step S3 is 2.0.

[0009] As a preferred solution, the different time scales in step S5 include months, days, and hours.

[0010] Due to the adoption of the above technical solution, the present invention has the following beneficial effects compared with the prior art: (1) By coupling an aerosol thermodynamic model into the Earth system model, the physical and chemical mechanisms of the model aerosols are enriched and the simulation of nitrate aerosols is achieved, providing an important tool for studying the global aerosol distribution, changes and environmental effects.

[0011] (2) Based on the high-resolution Earth system model, the model's ability to simulate aerosols has been improved, the model simulation bias has been reduced, and the credibility of atmospheric pollution forecasts has been enhanced.

[0012] (3) Select reasonable dust emission adjustment factors to improve the rationality of the model's simulation of dust emissions.

[0013] (4) According to the difference in the absorption coefficient of nitric acid gas in mineral dust, the mass transfer coefficient of nitric acid gas with respect to dust particles is adjusted to correct the underestimation of nitrate aerosol in the model.

[0014] Additional aspects and advantages of the present invention will become apparent from the following description or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of the species composition of the model aerosol of the present invention; Figure 2 This invention is PM in China, the United States, and Europe 2.5 The simulation effect is shown in the form of a scatter plot. DETAILED DESCRIPTION

[0016] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0017] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0018] Combine the following Figure 1 to Figure 2 The improved method for simulating particulate matter based on a high-resolution earth system model according to an embodiment of the present invention is described in detail.

[0019] The present invention proposes an improved method for particulate matter simulation based on a high-resolution Earth system model. Based on high-resolution Earth system simulation, coupled aerosol thermodynamics model, enriched the chemical mechanism of particulate matter simulation, further corrected the dust emission factor, adjusted the nitric acid gas absorption coefficient, and improved the refined simulation of particulate matter and its components. Specifically, it includes the following steps: Step S1, coupling the aerosol thermodynamic model: The Earth system model lacks aerosol thermodynamic processes, which regulate the solid-gas distribution of aerosols, and is crucial for simulating aerosols generated by semi-volatile gases. The aerosol thermodynamic model is based on the principles of thermodynamics and phase equilibrium, taking into account diffusion, deposition, chemical processes, etc., and can achieve an approximate simulation of the thermodynamic dynamic distribution process of aerosols. For the thermodynamic model, this patent uses the MOSAIC (Model for Simulating Aerosol Interactions and Chemistry) model, which is maturely used in common atmospheric chemistry models such as WRF-Chem. The model uses the time-splitting Euler method with an adaptive step size to deal with the gas phase particle distribution problem, which effectively improves its own calculation efficiency while ensuring the accuracy of the simulation, and is suitable for global scale and higher resolution model simulations. The aerosol module in the Earth System Model uses the four-mode aerosol module MAM4, and couples the aerosol thermodynamic model MOSAIC to the aerosol module MAM4 in the Earth System Model. MAM4 includes four modes: Agen core membrane, accumulation mode, coarse mode, and primary carbon; the existing aerosol species include sulfate aerosol, black carbon aerosol, dust aerosol, sea salt aerosol, primary organic aerosol, and secondary organic aerosol. Figure 1 As shown in Figure 2, based on the existing aerosol species, new species including nitrate NO were added. 3 - 、Ammonium salt NH 4 + , sodium Na + , chlorine - Calcium 2+ 、Carbonate CO 3 2- To the default parameter list (namelist) file, the aerosol basic parameter initial definition script (modal_aero_data.F90), the aerosol concentration calculation update file (sox_cldaero_mod.F90), and the sea salt and dust aerosol calculation script. Nitrate NO 3 - Except for density, molecular weight, and hygroscopicity, other physical properties of the aerosol are set to be consistent with those of sulfate aerosol.

[0020] Step S2, preparation of model simulation conditions: The model simulation process in this patent adopts a higher spatial resolution, so the various input conditions in the model also adopt high-resolution data accordingly, which mainly include atmospheric pollutant emission inventory, meteorological forcing field, etc.; among them, the anthropogenic source emission inventory adopts the 0.1° Global Anthropogenic Source Emission Inventory (CAMS-GLOB-ANT) released by the Copernicus Monitoring Service (CAMS), the biomass combustion source adopts the 0.1° Fire Emission Inventory (FINN) released by the National Center for Atmospheric Research (NCAR) of the United States, and the climate forcing field adopts the reanalysis data of the Global Land Actual Evaporation Dataset (MERRA-2).

[0021] Step S3, dust emission flux adjustment: Dust emission is highly sensitive to model resolution. After improving the resolution, the dust emission factor needs to be used for targeted adjustment. After the adjustment, the simulated global dust aerosol optical thickness is relatively reasonable. The dust emission flux calculation formula is as follows: (1) in, cflx represents the dust emission flux, idust Indicates dust particles of a certain size range. ndust is the total number of dust particle size segments, dust_in represents the dust emission simulated by the land surface model, dust_scl is the dust emission distribution coefficient, soil_erod The soil erosion capacity, soil_erod_fact is the dust emission adjustment factor; increasing the model resolution often leads to an increase in dust emissions, and the adjustment factor should be increased accordingly (the low resolution value is set to 0.7) to make dust emissions reasonable. This patent has been tested and the dust emission adjustment factor has been corrected to 2.0, thereby optimizing the dust aerosol simulation results and improving the accuracy of the simulation results.

[0022] Step S4, mineral dust absorption factor adjustment: In the aerosol thermodynamic process, the absorption coefficient of semi-volatile gas on the surface of different particles ( γ ) are different, which leads to the calculation of the mass transfer coefficient of semi-volatile gas between gas / liquid phase and solid phase ( α ) are quite different. According to field observations, HNO 3 The absorption coefficient of gas on the surface of mineral dust is about 1-3 orders of magnitude lower than that of other particles, while HNO 3 Gas condensation is one of the important sources of nitrate aerosols and is crucial for accurate simulation of nitrate aerosols. 3 The mass transfer coefficient in mineral dust is calculated as follows: (2) According to the literature, the absorption coefficient of nitric acid gas on dust particles ranges from 0.1×10 -3 to 0.21, the absorption coefficient in the mode ( γ ) is taken at a relatively low level (0.0011). Based on actual observations, this patent will set up sensitivity tests, use different absorption coefficients (0.0011, 0.01 and 0.1) to simulate and evaluate the nitrate aerosol concentration, and finally select and adjust the appropriate absorption coefficient ( γ ) value, thus making the nitrate concentration relatively reasonable; Step S5: The model will output high-resolution aerosol, gas concentration and meteorological data at different time scales (month, day, hour) according to the needs. The script will be written based on NCL to batch process the output results and save them as NetCDF files. For aerosol species, it is necessary to convert their units based on data including temperature and air pressure to facilitate comparison with observation data. The script is designed to realize simultaneous output and processing, and the results are saved in an external network attached storage (NAS) system. Step S6: Visualize the obtained aerosol, gas and meteorological data. Based on the NCL language, a batch processing program is used to realize the visualization of the output results. The output results are interpolated using the ESMF function of NCL to facilitate comparison with the observed data. The visualization scheme includes time series diagrams, spatial distribution diagrams and scatter diagrams. Step S7, model evaluation: The meteorological observation data used for evaluation are ERA5 reanalysis data of the European Centre for Medium-Range Weather Forecasts, with a resolution of 0.25 degrees; PM 2.5 The data of the European Monitoring and Evaluation Programme (EMEP) and the Inter-agency Monitoring of the Protected Visual Environment (IMPROVE) were used for the PM 2.5 The concentration data comes from the China National Environmental Monitoring Center, and the particulate matter component data uses the China Atmospheric Composition Near-Real-Time Tracking Dataset (TAP) released by Tsinghua University. The observation results are interpolated to a 0.25 degree grid and compared with the model results and presented in graphical and tabular form.

[0023] like Figure 2 As shown, the seasonal average PM in Europe, the United States and China in summer 2019 2.5The correlation between the observation and simulation results is shown in the form of a scatter plot. The vertical axis is the simulation result, the horizontal axis is the observation result, and the dotted lines of different colors represent different test cases. Green represents the low-resolution unoptimized result, blue represents the low-resolution optimized result (coupled thermodynamic model, adjustment of dust emission and absorption coefficient), purple represents the high-resolution unoptimized result, and red represents the optimized result (coupled thermodynamic model, adjustment of dust emission and absorption coefficient). The average value of the observation and simulation has been marked in the upper left corner, and the correlation and slope results of different simulation results are also marked. Overall, through optimization measures such as coupling thermodynamic models, improving model resolution and adjusting parameters, the Earth System Model CESM has improved the PM2.5 over China and Europe. 2.5 The simulation effect has been greatly improved, but the improvement is relatively unobvious for areas that are relatively less affected by inorganic aerosols such as nitrates (such as the United States).

[0024] In the description of the present invention, the term "plurality" refers to two or more than two. Unless otherwise clearly defined, the orientation or positional relationship indicated by the terms "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation of the present invention; the terms "connection", "installation", "fixation", etc. should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0026] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An improved method for simulating particulate matter based on a high-resolution Earth system model, characterized in that , specifically including the following steps: Step S1, coupling aerosol thermodynamic model: aerosol simulation in the Earth system model uses the four-mode aerosol module MAM4, including four modes: Agen core membrane, accumulation mode, coarse mode and primary carbon; the aerosol thermodynamic model MOSAIC is coupled to the aerosol module MAM4, and the existing aerosol species include sulfate aerosol, black carbon aerosol, dust aerosol, sea salt aerosol, primary organic aerosol and secondary organic aerosol; on this basis, new species are added including nitrate NO3 - 、Ammonium salt NH4 + , sodium Na + , chlorine - Calcium 2+ 、Carbonate CO3 2- Insert the relevant new species into the default parameter list namelist file, the aerosol basic parameter initial definition script modal_aero_data.F90, the aerosol concentration calculation update file (sox_cldaero_mod.F90), and the sea salt and dust aerosol calculation scripts; Step S2, model simulation condition preparation: the input conditions in the model use high-resolution data, including anthropogenic emission inventory, biomass burning source and meteorological forcing field; the anthropogenic emission inventory uses the 0.1° global anthropogenic emission inventory CAMS-GLOB-ANT released by the Copernicus Observation Service CAMS, the biomass burning source uses the 0.1° fire emission inventory FINN released by the National Center for Atmospheric Research NCAR, and the climate forcing field uses the reanalysis data of the global land actual evapotranspiration dataset MERRA-2; Step S3, dust emission flux adjustment: Dust emission is highly sensitive to model resolution. After improving the resolution, the dust emission factor needs to be used for targeted adjustment. After the adjustment, the simulated global dust aerosol optical thickness is relatively reasonable. The dust emission flux calculation formula is as follows: （1） in, cflx represents the dust emission flux, idust Indicates dust particles of a certain size range. ndust is the total number of dust particle size segments, dust_in represents the dust emission simulated by the land surface model, dust_scl is the dust emission distribution coefficient, soil_erod The soil erosion capacity, soil_erod_fact is the dust emission adjustment factor; Step S4, HNO3 gas key coefficient adjustment: The mass transfer coefficient of HNO3 in mineral dust in the model is calculated as follows: （2） Absorption coefficient in mode γ The value of is 0.0011; Step S5: The model will output high-resolution aerosol, gas concentration and meteorological data of different time scales as needed. The script will be written based on NCL to batch process the output results and save them as NetCDF files. For aerosol species, it is necessary to convert their units based on data including temperature and air pressure and compare them with the observed data. The script is designed to realize simultaneous output and processing, and the results are saved in an external network attached storage NAS system. Step S6: Visualize the obtained aerosol, gas and meteorological data, and realize the visualization of the output results based on the NCL language; use the ESMF function of NCL to interpolate the output results and compare them with the observed data. The visualization scheme includes time series diagram, spatial distribution diagram and scatter diagram; Step S7, model evaluation: The meteorological observation data used for evaluation are ERA5 reanalysis data of the European Centre for Medium-Range Weather Forecasts, with a resolution of 0.25 degrees; PM 2.5 The data of PM and its components were respectively obtained from the European Monitoring and Evaluation Program (EMEP) and the Inter-Agency Monitoring of the Protected Visual Environment (IMPROVE). 2.5 The concentration data comes from the China National Environmental Monitoring Center, and the particulate matter component data uses the China Atmospheric Composition Near-Real-Time Tracking Dataset TAP released by Tsinghua University. The observation results are interpolated to a 0.25 degree grid and compared with the model results and presented in the form of graphs and tables.

2. The improved method for simulating particulate matter based on a high-resolution earth system model according to claim 1, characterized in that , the new species sodium Na in step S1 + , chlorine - The sum of the two aerosols represents sea salt aerosol, while dust is composed of 2% calcium Ca 2+ , 3% carbonate CO3 2- and 95% of other inorganic substances not explicitly specified.

3. The improved method for simulating particulate matter based on a high-resolution earth system model according to claim 1 is characterized in that , the dust emission adjustment factor is 2.

0.

4. The improved method for simulating particulate matter based on a high-resolution earth system model according to claim 3 is characterized in that , the absorption coefficient is corrected to 10 -2 .

5. The improved method for simulating particulate matter based on a high-resolution earth system model according to claim 1 is characterized in that ,The different time scales in the step S4 include months, days and hours.

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