Implementation and Evaluation of Irrigation Techniques in the Community Land Model

作者：Yi Yao, Inne Vanderkelen, Danica Lombardozzi, Sean Swenson, David M. Lawrence, Jonas Jägermeyr, Luke Grant, Wim Thiery · 发表于：Journal of Advances in Modeling Earth Systems · 年份：2022 · DOI：10.1029/2022ms003074 · 被引用次数：49 · 研究领域：Water-Energy-Food Nexus Studies、Water resources management and optimization、Plant Water Relations and Carbon Dynamics

Abstract Several previous studies have highlighted the irrigation‐induced impacts on the global and regional water cycle, energy budget, and near‐surface climate. While land models are widely used to address this question, the implementations of irrigation in these models vary in complexity. Here, we expand the representation of irrigation in Community Land Model to enable six different irrigation methods. We find that using a combination of irrigation methods, including default, sprinkler, flood and paddy techniques performs best as determined by evaluating the simulated irrigation water withdrawals against observations, and therefore select this combination as the new irrigation scheme. Then, the impact of the new irrigation scheme on surface fluxes is evaluated and detected using single‐point simulations. Finally, the global and regional irrigation‐induced impacts on surface energy and water fluxes are compared using both the original and the new irrigation scheme. The new irrigation scheme substantially reduces the bias and root‐mean‐square error of simulated irrigation water withdrawal in the USA and other countries, but considerably overestimates withdrawals in Central China. Results of single‐point experiments show that different irrigation methods have different effects on surface fluxes, while the magnitudes are small. At the global scale, the new scheme enlarges the irrigation‐induced impacts on water and energy variables relative to the original scheme, with varyin...