An Integrated Agriculture, Atmosphere, and Hydrology Modeling System for Ecosystem Assessments
Ran, L., Y. Yuan, E. Cooter, V. Benson, Jon Pleim, R. Wang, AND J. Williams. An Integrated Agriculture, Atmosphere, and Hydrology Modeling System for Ecosystem Assessments. Journal of Advances in Modeling Earth Systems. John Wiley & Sons, Inc., Hoboken, NJ, 11(12):4645-4668, (2019). https://doi.org/10.1029/2019MS001708
Human activities such as agricultural fertilization and fossil fuel combustion have introduced a massive amount of anthropogenic nitrogen (N) in reactive forms to the environment. As agricultural fertilization is the single largest anthropogenic N source, an integrated approach to understand the interactions among agriculture, atmosphere, and hydrology is essential in examining human-altered N cycling. We have developed an integrated modeling system with agriculture EPIC, atmosphere WRF/CMAQ, and hydrology SWAT. This integrated system is useful tool for scientists and policy-makers to answer many questions on cycling of water, carbon, and nutrients for sustaining the food production while protecting the environment.
We present a regional‐scale integrated modeling system (IMS) that includes Environmental Policy Integrated Climate (EPIC), Weather Research and Forecast (WRF), Community Multiscale Air Quality (CMAQ), and Soil and Water Assessment Tool (SWAT) models. The centerpiece of the IMS is the Fertilizer Emission Scenario Tool for CMAQ (FEST‐C), which includes a Java‐based interface and EPIC adapted to regional applications along with built‐in database and tools. The SWAT integration capability is a key enhanced feature in the current release of FEST‐C v1.4. For integrated modeling demonstration and evaluation, FEST‐C EPIC is simulated over three individual years with WRF/CMAQ weather and N deposition. Simulated yearly changes in water and N budgets along with yields for two major crops (corn grain and soybean) match those inferred from intuitive physical reasoning and survey data given different‐year weather conditions. Yearlong air quality simulations with an improved bidirectional ammonia flux modeling approach directly using EPIC‐simulated soil properties including NH3 content helps reduce biases of simulated gas‐phase NH3 and NH4+ wet deposition over the growing season. Integrated hydrology and water quality simulations applied to the Mississippi River Basin show that estimated monthly streamflow and dissolved N near the outlet to the Gulf of Mexico display similar seasonal patterns as observed. Limitations and issues in different parts of the integrated multimedia simulations are identified and discussed to target areas for future improvements.