1. FEST-C for Bi-directional CMAQ: Update Ellen Cooter U.S. EPA, National Exposure Research Lab, Research Triangle Park, NC Verel Benson Benson Consulting, Columbia, MO Limei Ran Institute for the Environment, University of North Carolina, Chapel Hill, NC 19 September, 2013

2. Outline Drivers Implementation of the linked agricultural management and air quality system Agricultural management model overview A tool to generate fertilizer input information for gridded air quality models Model performance improvement Applications

3. 3 Research Drivers Increases during the last several decades in regional-to-global air, land and water nitrogen (N) inputs pose a growing threat to human health and ecosystem sustainability. Policy actions that address this threat demand improved characterization of all aspects of the N-cycle, including air quality.

4. Areas in need of improved treatment include: Characterization of nitrogen species such as NH 3 that exhibit bi-directional air-surface exchange. More complete integration of agricultural practices and meteorologically-driven emissions to reduce NH 3 and inorganic PM 2.5 concentration and deposition uncertainty. Development of the capacity to explore options that support joint air, land and water environmental outcomes to protect human health and ecosystems (i.e., MDST3).

5. All three of these areas are addressed through the linked EPIC/Bi-directional CMAQ or BIDI system, whose focus is improving estimates of soil ammonia emissions

6. Soil emissions can be important ~85% of ammonia emissions come from agriculture and ~ 75% of agricultural emissions come from livestock production. Livestock operations are primarily NH 3 emitters (unidirectional), so flux is estimated relatively easily as a function of livestock numbers and meteorology. Crop soil flux is often bidirectional (emissions and deposition) and is a complex function of farm management, weather, ambient atmospheric and soil concentrations. Sensitivity studies of bi-directional CMAQ suggest that soil emission potential (Γ s ), a function of fertilizer application rate, depth, atmospheric deposition and nitrification rate, is an important source of NH 3 emission uncertainty (Dennis, et al., 2013). Therefore, is it important to use the best estimates of fertilizer nitrification and application rate and depth as possible.

7. Implementation in Bidirectional CMAQ Cooter et al. (2012)

8. Simulates C, N, P biogeochemistry for spatial scales ranging from a single field site to global gridded domains at a daily time step Addresses natural as well as intensively managed terrestrial systems Widely used and internationally vetted The Environmental Policy Integrated Climate (EPIC) model

10. How do you get the initial soil ammonium and pH conditions and the daily fertilizer application and depth to run BIDI?

11. The FEST-C User Interface – facilitates user-generated CMAQ-ready fertilizer input for any gridded domain, grid cell resolution and weather year by creating and running executable scripts.

12. Open Scenario New Scenario Copy Scenario Save Scenario Delete Scenario Exit Scenario Scenario creation requires minimal inputs

13. BELD Data Generation creates a BELD landuse coverage matching the domain and grid resolution of the scenario.

14. WRF/CMAQ to EPIC inputs metcro2D and an initial atmospheric deposition estimate as zero, an EPIC default value of.8 ppm or from a previous CMAQ run. GEOSChem weather must be processed externally.

15. User can select one, several or all crops Multiple weather year simulations require only the new weather data and this step be re-run.

16. FEST-C Input to CMAQ

17. The system does a reasonable job reproducing regional patterns of reported agricultural fertilizer purchases and use EPIC Application Fertilizer Sales Gronberg and Spahr (2012)

18. Agricultural management information can be produced for various CMAQ domains to address questions of spatial scale

19. …and for extended periods of time. Nitrate fertilizer annual variability can be large and its simulation is critical to the estimation of ecosystem services such as clean water. EPIC facilitates integration across air, land and water media by using WRF driving weather to provide consistent farm management and biogeochemcial inputs to other linked models. There is little annual variability in NH 3 fertilizer applications in the U.S. because farmers lack a priori weather and market information at application time.

20. The importance of interannual variability for NH 3 emissions lies in met-driven application timing. 2003 2006

21. The integration of agricultural land management information with a bi-directional regional air quality modeling approach improves estimates of atmospheric deposition and particulate matter. Speciation Trends Network NO 3 - comparison (Bash et al., 2013)

22. Future Coupled Air Quality/Agricultural N Applications for Human and Ecosystem Health Biofuels (ongoing) Goal: Assess air quality and ecosystem service responses to land use and land management change associated with biofuel production Gulf of Mexico Hypoxia (GOM) (ongoing) Goal: Reduce the GOM hypoxic zone extent through identification of alternative land use/land management options that could moderate nutrient loadings to the Mississippi watershed (include additional water model linkage). Agricultural soil N 2 O emissions(ongoing) Goal: Develop a better understanding of regional N 2 O emissions from agricultural soils, improve N 2 O emission inventories and identify potential mitigation strategies. Climate Change (planned) Goal: Explore joint air quality, water quantity and water quality implications of future climate change.

23. Public release of the interface will happen at CMAS FEST-C currently supports both NCC and UNC computer systems. There will be a poster and a terminal set up for folks to try out the interface at CMAS There will be a web page on the CMAS site for FEST-C that includes download and installation instructions and system documentation.

24. Questions? Ellen Cooter U.S. EPA, National Exposure Research Lab, Research Triangle Park, NC