Evaluation of Climate Change On N2Ο Emissions in Agroecosystems.

Understanding the effects of climate change on nitrous oxide (N₂O) emissions in agroecosystems is important because agricultural soil management activities, such as fertilizer application and other cropping practices is a major contributor of N₂O emissions in the United States. Climate change impacts involve developing plausible future climate scenarios to be used in a process based N₂O model at the regional level. The objective of this study was to analyze future climate scenarios of daily precipitation, maximum and minimum temperatures, and N₂O to evaluate potential effects of climate change on N₂O emissions from corn fields across Kansas. Change Factor Methodology (CFM) was used to derive plausible future scenarios of precipitation and temperatures from Regional Climate Models (RCM). The daily simulations from multiple RCMs were obtained from North American Regional Climate Change Assessment Program (NARCCAP) for grid box closest to the centroid of 23 weather stations in Kansas for baseline (20C3M, 1968-2000) and future (A2, 2038-2070) time periods. The Denitrification and Decomposition (DNDC) model was used to simulate N₂O emissions. Preliminary results indicated an increase in temperatures across the state and the rate of increase varied among the stations. In the case of precipitation, there was variability in the rate and direction of change across the state. As a result of changes in climate,  N₂O emissions predicted from the DNDC model was highly variable due to changes in climate and agricultural management practices.