Grantee Research Project Results
1997 Progress Report: Development and Application of an Air Quality Modeling System with Integrated Meteorology, Chemistry, and Emissions
EPA Grant Number: R825388Title: Development and Application of an Air Quality Modeling System with Integrated Meteorology, Chemistry, and Emissions
Investigators: Xiu, Aijun , Alapaty, Kiran , Coats, Carlie J. , Mathur, Rohit
Current Investigators: Xiu, Aijun , Mathur, Rohit , Hanna, Adel , Coats, Carlie J.
Institution: MCNC / North Carolina Supercomputing Center
EPA Project Officer: Hahn, Intaek
Project Period: October 1, 1996 through September 30, 1999
Project Period Covered by this Report: October 1, 1996 through September 30, 1997
Project Amount: $372,830
RFA: Exploratory Research - Air Engineering (1996) RFA Text | Recipients Lists
Research Category: Land and Waste Management , Air , Safer Chemicals
Objective:
To develop a fully-integrated, physically and numerically consistent, regional-scale coupled atmospheric dynamics and chemistry modeling system.Progress Summary:
The research performed in the first year of the project has focused on three major aspects: (1) A detailed review of the MM5 system and identification of portions of the code that would require modification to aid the introduction of tracer species in the model; (2) Initiation of design and development of an interface between emissions processing model and the integrated model; and (3) Implementation and initial testing of tracer transport within the MM5 modeling system.
Accomplishments and Research Results:
1. The MM5 System: Review and acquisition
Recently, National Center for Atmospheric Research (NCAR) released the version 2 of the MM5 modeling system. Compared to its predecessors, the latest version is more robust and has additional options for representation of various physical processes. At the onset of this project we made a decision to use this version of MM5 as the base for the integrated model. We acquired from NCAR the code for MM5 Version 2 (MM5V2) and completed the installation of the system on the Cray T90 at North Carolina Supercomputing Center (NCSC). To facilitate an organized way of specifying input parameters that control various physical and dynamical processes, we have developed a scripting language code. This script allows a user to change or modify MM5V2 parameters easily and also provides a cross check for consistency among the chosen input parameters. This scripting code was successfully tested for its functionality on the Cray T90. A test run was successfully completed for a 48 hour simulation. In addition, the research work with the land-surface model (Pleim and Xiu, 1995) in MM5 under a separate EPA funded cooperative agreement has been continued. This work forms the foundation for incorporating biogenic emission and dry deposition processes into MM5 since the land-surface model provides the essential information such as sensible heat and latent heat fluxes, stomata resistance, and surface temperature. Results from this work were presented in the MM5 User's Workshop.
Considerable effort was also devoted to the review of the MM5 system to aid in identification of portions of the code that would require modification for introduction of tracers in the system. In particular, attention was devoted towards identifying internal variables that would be required for driving the tracer transport and chemistry calculations. These aspects are further discussed subsequently.
2. Design and Development of Emissions Interface
The emissions processing module requires various meteorological variables as input. The emissions processing module to be used in this work is the Sparse Matrix Operator Kernel Emissions (SMOKE) model developed at NCSC. The model has been carefully designed to circumvent several of the computational bottlenecks of other emissions processing systems. In order to couple the emissions processing within the integrated modeling system, we investigated two possible approaches: (a) inclusion of the entire emissions processing module within the integrated system; and (b) development of an appropriate interface that would facilitate the transfer of requisite meteorological variables to the emissions processor and provide the processed emissions to the integrated model. Analysis indicated that including the functionality of the SMOKE emissions model directly into a monolithic executable for the integrated meteorology/air quality model would add more than 120 megawords to the size of the executable. The resulting executable would not be feasible to run on NCSC's Cray T-90. The project will instead take advantage of the new Model-Coupling Mode of the Models-3/EDSS Input/Output Applications Programming Interface (I/O API), which has been developed at NCSC as part of the "Practical Parallel" cooperative agreement with EPA, to couple SMOKE running on a large-memory workstation server with the rest of the integrated model running on the T-90. Note that I/O API Model-Coupling Mode has been completely implemented and tested by the Practical Parallel Project.
Since the MM5 sequential file output is incapable of the coordination required for model coupling, we have constructed an MM5-I/O API module which directly generates I/O API files (or coupling-channels) from MM5 without requiring the existing interface program, the Meteorology Chemistry Interface Processor (MCIP). The development and implementation of this module has been leveraged through other existing projects within our group such as the Practical Parallel project and the Hydrology-Meteorology Coupling project.
3. Implementation and initial testing of tracer transport
As a first step towards the inclusion of detailed treatment of chemical tracers in the MM5, we incorporated tracer advection within the MM5. The advection scheme chosen for this initial implementation is the Smolarkiewicz scheme. A central objective of this phase of the study is to implement tracer advection in a consistent manner such that tracer mass-conservation is strictly obeyed in the model. A variety of test cases have been simulated with this initial version of the model to test mass-conservation of 3-D tracer advection. These test cases involve the transport of a spatially uniform mixing ratio field, with specified boundary conditions, and the transport of an initial instantaneous source. For a truly conservative system, the advection should retain the uniform mixing ratio field in the first test. In the second test, the total mass within the domain should be conserved as long as the initial puff is within the modeling domain. Based on these two tests, we are evaluating the conservative properties of the tracer advection code. We have also devoted some effort towards modifying the chemistry module used in our off -line chemistry/transport model to make it compatible for incorporation in the integrated model.
In a parallel effort we have also collaborated with Dr. P.Kasibhatla (Duke University) and Ms. U.Shankar (MCNC-NCSC) who are investigating similar activities in the Regional Climate Model (RegCM2), under a NASA funded project. Given the similarity between the MM5 and RegCM2 systems, these collaborative efforts have provided significant leverage to this initial task. In this work, the tracer was advected using the same advection scheme as that used for cloud water in the RegCM2. In addition, the Radon222-Pb210 system was also included in the model to investigate the transport characteristics. Initial results from this study were presented at annual meeting of the American Association for Aerosol Research.
Dr. Georg Grell at the Fraunhofer Institute for Atmospheric Environmental Research in Germany is leading an effort to include the treatment of chemical tracers as represented in the Regional Acid Deposition Model, within the MM5V2. Dr. Grell visited with our team in September 1997 and we have established collaborative effort with his team to share development on the integrated model. We have also received a copy of the code developed by his team and are performing initial testing of the transport scheme in their model.
Reference
Pleim, J.E. and A.Xiu, 1995: Development and testing of a surface flux and planetary boundary layer model with explicit soil moisture parameterization for application in mesoscale models. Journal of Applied Meteorology, Vol. 34, pp16-32.
Future Activities:
We will complete our testing of tracer advection in MM5 and the mass conservation analysis. We will complete the testing of the MM5-I/O API module to facilitate the transfer of appropriate meteorological inputs to the emissions processing module and the chemistry transport module. Subsequent to this testing we will initiate the integration of other process modules (chemistry, turbulent mixing, cloud transport and aqueous chemistry) into MM5. At each step of the process integration we will perform test simulations geared towards isolating any possible errors that may have been introduced in the integration process. Once all the chemistry/transport modules are integrated within the MM5 we will initiate comparative studies of the integrated model with off-line calculations for a selected test episode for the summer of 1995. We anticipate presenting the results of these comparisons at a technical meeting and documenting them in form of a journal article.
Financial and Administrative Information:
We started this project a little later than the official starting date since much background research had to be done at the initiation of the project. Further, we decided to use the latest version of MM5 as a base for the integrated model and some delay was also encountered in acquiring MM5V2 from NCAR and in its subsequent installation and testing on the CRAY T90 at NCSC. In addition, since some of the initial development performed for this project has been leveraged on other existing project within our group, only 35% of the targeted budget for the first year was expended. We anticipate that for the second year our budget will be on target.
Journal Articles:
No journal articles submitted with this report: View all 8 publications for this projectSupplemental Keywords:
atmospheric, quantitative, air pollution, ozone, modeling system, aerosol, RFA, Scientific Discipline, Air, particulate matter, air toxics, Environmental Chemistry, Environmental Monitoring, tropospheric ozone, Engineering, meteorology, air quality models, ambient air, emission-based modeling, ozone, chemical composition, air pollution models, air quality data, atmospheric aerosols, atmospheric aerosol particles, atmospheric chemistry, engineering modelsProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.