Soil water management and climate fluctuations: modelling approach

Authors: Baffaut, Claire; COSTELLO, CHRISTINE - Pennsylvania State University; GAUTAM, SAGAR - Sandia National Laboratory; PHUNG, QUANG - University Of Missouri; THOMPSON, ALLEN - University Of Missouri

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 7/29/2021
Publication Date: 12/11/2022
Citation: Baffaut, C., Costello, C., Gautam, S., Phung, Q., Thompson, A. 2022. Soil water management and climate fluctuations: modelling approach. In: Blanco, H., Kumar, S., and Anderson, S.H., editors. Soil Hydrology in a Changing Climate. Clayton South, Australia: CSIRO Publishing. p. 233-250.

Interpretive Summary: Globally around 70% of the fresh water is used in the agriculture sector, therefore wisely managing the water usage in agriculture is critical to achieving sustainability. The projected increase in demand of water across sectors (e.g., power generation, agriculture, households, industry) under higher population density and the interaction with the future climate change requires intervention. Earth System Models (ESM), which predict how the climate will change, and eco-hydrologic models, which simulate how production and environmental systems respond to weather and management practices, are necessary tools to predict how agricultural systems will respond to climate change and what soil water management practices can mitigate the effects. The objectives of this chapter are to provide an understanding about the types of soil water management issues addressed with ESMs and eco-hydrologic models; describe the current state of the art for how eco-hydrologic modelling can assist with soil water management decisions in a changing climate; and describe opportunities for model improvement necessary for addressing soil water management in a changing climate. While major challenges remain, and complete eradication of modeling uncertainty may never be achievable, the coupling of ESM with eco-hydrological and crop models has improved our ability to determine which management options can alleviate emerging risks across space and time. The modeling efforts can improve our ability to understand the future trajectory of soil water status under different land use, crop and water management practices and climate scenarios over time.

Technical Abstract: Globally around 70% of the fresh water is used in the agriculture sector, therefore wisely managing the water usage in agriculture is critical to achieving sustainability. The projected increase in demand of water across sectors (e.g., power generation, agriculture, households, industry) under higher population density and the complex interaction with the future climate change entails the need for intervention. Earth System Models (ESM) and eco-hydrologic models are necessary tools to predict how agricultural systems will respond to climate change and what soil water management practices producers and water resource managers can implement to mitigate the effects. The objectives of this chapter are to provide an understanding about the types of soil water management issues addressed with ESMs and eco-hydrologic models; describe the current state of the art for how eco-hydrologic modelling can assist with soil water management decisions in a changing climate; and describe opportunities for model improvement necessary for addressing soil water management in a changing climate. There is great progress and remaining need to improve the ability to accurately assess, via the individual and coupled models described herein, which management options can alleviate emerging risks across space and time. In particular, the certainty of the predictions needs to be sufficient to warrant local, regional, national and even global decision-making about investment in and placement of infrastructure, biotechnology, crop and irrigation management options. The wealth of knowledge gained from experimental studies can be used to benchmark/train eco-hydrologic models and design sustainable management systems that are resilient to future changes in climate. Simultaneously, there has been significant progress made in ESMs, which provide a range of ever-improving data on the future trajectory of Earth’s climate. While major challenges remain, and complete eradication of uncertainty may never be achievable, the coupling of ESM with eco-hydrological and crop models has improved over time. Much effort is being spent to continue to improve these models individually and in their ability to be coupled. The modeling efforts can improve our ability to understand the future trajectory of soil water status under different land use, crop and water management practices and climate scenarios over time.