Investigating the response of land-atmosphere interactions and feedbacks to heterogeneity imposed by irrigation

Anthropogenic modifications to the terrestrial water cycle, such as irrigation abstraction and application, can affect land-atmosphere interactions and local to regional weather. A necessary step in accurately representing such processes in coupled models is to define where, when, and how much irrigation occurs spatially. Traditionally, such information was defined using spatial maps of areas equipped for irrigation. However, recent advancements in irrigation mapping enabled by improved remote sensing and data processing technology have yielded higher resolution (in both time and space) irrigation information. This study uses a suite of offline and coupled simulations using NASAs Land Information System (LIS) and NASAs Unified Weather Research and Forecasting (NU-WRF) system to investigate the impact of irrigation induced heterogeneity of varying scales on land-atmosphere interactions in eastern Nebraska. In particular, the impacts of irrigation map resolution on land surface heterogeneity and subsequent impacts on land-atmosphere coupling are explored during the NSF-funded Great Plains Irrigation Experiment (GRAINEX) Field Campaign in 2018.