A looming question for society is the effect of climate change on crops and, in turn, the effects of agricultural land use and management on climate. To help researchers address such issues, Sam Levis, part of Gordon Bonan's team of researchers in the Terrestrial Science Section (ESSL / CGD), is coupling a crop model to the land component (CLM) of the NCAR-based Community Climate System Model.
The new model will simulate different leaf areas and yields for wheat, corn, and other crops in response to temperature and soil moisture scenarios. In a proof-of-concept simulation, Levis demonstrated a correlation between higher precipitation levels and greater leaf area for a variety of crops in the Midwest.
His next step is to link the crop model to CLM’s carbon-nitrogen cycling model in order to simulate biogeochemical effects of land use and management on the climate system. The goal is to add the crop simulations to the CCSM's land component in about a year.
CLM Model Components: Dynamic Vegetation
Projects
There are two main projects related to dynamic vegetation. Peter Thornton is leading an effort to add the carbon and nitrogen cycles to the Community Land Model. This uses carbon and nitrogen parameterizations of the BIOME-BGC model. Vegetation structure (e.g., leaf area index, carbon pools) changes over time, but community composition is prescribed. Gordon Bonan and Sam Levis are leading an effort to allow for dynamic community composition. The current implementation of dynamic vegetation uses many ideas formulated in the Lund-Potsdam-Jena dynamic global vegetation model. [read more]
