CAREER: Predicting Climate Impacts on Irrigated Agriculture

Dartmouth College, Hanover NH

Investigators

Abstract

This project will assess the effects of climate and water supply on future irrigated agricultural production. Increasing agricultural production through irrigation is an essential part of the complex solution to global hunger. Irrigation can make marginal land suitable for agriculture and existing croplands more productive. However, irrigation is limited by its massive use of water. Determining the potential of irrigation to reduce global hunger requires a thorough understanding of multiple factors such as climate, agricultural water supply, and crop production. This project will improve predictions of climate impacts on irrigated croplands by advancing the understanding of key constraints on irrigated agricultural productivity. As a result, it will develop strategies for enhancing future irrigation management. Knowledge, data, and models will be widely disseminated both directly and through collaborations with the Agricultural Model Intercomparison and Improvement Project and Kansas Geological Survey. This project will also increase knowledge of physical geography, climate science, numerical modeling, and data analysis for students at critical STEM stages. Additionally, the investigator will create a teaching model that enables high-school students to explore the impacts of climate and water resources on crop production, develop an educator professional development course for the teaching model, and provide research experiences for diverse graduate and undergraduate students intending to major in a STEM field. Irrigated agricultural projections that directly simulate the impacts of water supply on yield are few, and typically have simplistic representations of crop growth and irrigation. This project will address this key deficiency through four main efforts: (1) Construct a modeling framework that connects climate and hydrologic data with a crop model capable of simulating limited automatic irrigation; (2) Evaluate and improve the modeling framework using reported yields and satellite-derived evapotranspiration, soil moisture, and vegetation index data; (3) Force the modeling framework with climate and water supply scenarios; and (4) Explore crop water use and production across irrigation scenarios and modeling assumptions. These efforts will provide answers to three important questions at the interface of climate, water, and agriculture: (1) What are the effects of water supply shortages on irrigated agricultural production?currently and in the future? (2) Which irrigation management practices can reduce water use without harming yields, and ultimately decrease the impacts of water scarcity on irrigated crop production? (3) How can satellite data improve crop model simulations of irrigated agricultural production? This project will focus on irrigated corn, soybean, rice, and wheat in the United States, where irrigation is responsible for approximately 90% of consumptive water use and $120 billion of agricultural production. However, datasets, models, and methods developed by this project will provide opportunities to improve projections of irrigated agriculture globally. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.