Performing Department
(N/A)
Non Technical Summary
Sustainable water availability is central to the long-term health, viability, and functioning of irrigated agroecosystems. Characterization of future water availability in these systems currently focuses on changes to water supply and water demand for crop evapotranspiration. Changes to agricultural water demand associated with managing increasingly extreme temperatures (e.g. via evaporative cooling) are not currently accounted for, but can be quite large, especially for perennial cropping systems. This increased demand challenges the sustainability of both agriculture (out-of-stream withdrawals) and the environment (instream flows), especially for water-stressed regions. Continued ignorance of this aspect raises the risk that irrigated agroecosystems are under-prepared to adapt to changing water availability. Our overarching goal is to advance the state-of-the-art of climate change impact assessments by building capacity to integrate the important but currently neglected agricultural water needs for extreme-temperature-management into the regional planning and decision-making efforts of a diverse range of stakeholders. Using irrigated watersheds in the Columbia River basin as a case study, we propose to develop and apply an integrated modeling framework to comprehensively characterize (i) the future regional agricultural water demands including the demands for extreme-temperature-management (ii) the impacts of this additional demand on agricultural and environmental water availability and shortages, and (iii) opportunities to address this additional demand and associated impacts and explore win-win outcomes for both crop production and environmental flows. This work will enhance our ability to identify adaptation alternatives to a changing climate that ensure nutritional security and healthy agricultural economies while protecting instream flows, thus enhancing agroecosystem sustainability.
Animal Health Component
0%
Research Effort Categories
Basic
30%
Applied
40%
Developmental
30%
Goals / Objectives
In fully-allocated watersheds where the demands are greater than the water supply, any changes in demand or supply will impact the ability to support agroecosystem services. Climate change impacts both demand and supply, and it is important to accurately quantify changes in both to best support regional planning, decision support, and adaptation efforts. Our early work suggests that water for extreme heat management is a key component of changes to agricultural water demands that is missing from current modeling and planning considerations. Integrating this missing component is critical to (a) evaluating the impacts of this change in demand on the ability of the agrosystem to support two agroecosystem services: water for crop production and environmental (instream) flows, and (b) identifying adaptation strategies to minimize the negative impacts on agroecosystem services. We propose to bridge this gap by building modeling capacity to incorporate this missing aspect, and performing model simulations to quantify the impacts of estimated changes in demand on the ability of the agroecosystem to support services and identify adaptation strategies. Our overarching goal is to advance the state-of-the-art of agroecosystem climate change impacts assessment by building capacity to incorporate the "important but currently neglected" aspect of "water needs for extreme heat management" into regional modeling, planning, and decision-making efforts. We expect that building this research and application capacity will (a) enhance our ability to explore adaptation alternatives to a changing climate that ensure nutritional security, regional economies, and farmer livelihoods while protecting environmental flows, and (b) allow regional agencies to better plan for climate change. Our specific objectives include:Objective 1: Build biophysical modeling capacity that accounts for agricultural water demands for extreme heat management.Objective 2: Comprehensively characterize historical and future agricultural water demands (with and without adaptation), and quantify associated uncertainties.Objective 3: Quantify changes (with and without adaptation) to two agroecosystem services--timing and magnitude of water availability for crop production and for environmental flows--as a result of future changes in water supply and demands.Objective 4: (a) Co-identify, with stakeholders, adaptation alternatives that minimize negative impacts to agroecosystem services and enhance irrigated-agroecosystem sustainability and (b) co-develop a path to integrate project findings into regional planning. While we focus on three contrasting watersheds in the Pacific Northwest US as case studies, we expect the modeling framework and the results to be translatable to any fully-allocated irrigated agroecosystem, including a majority of watersheds in the western United States.
Project Methods
The overview of tasks and methods for each objective are listed below.Objective 1: Build biophysical modeling capacity to account for agricultural water requirements for extreme heat management.This task includes updates to the CropSyst model (Tasks 1.1 and 1.2), field measurements to support model parameterization (Task 1.1), and integration of the updated CropSyst model into the regional-scale VIC-CropSyst modeling framework (Task 1.3).Task 1.1: Integrate the energy-balance model for estimating fruit surface temperature (FST) and its reduction via overhead sprinkler irrigation into the CropSyst model, and perform field measurements to help finetune key model parameters.Task 1.2: Developing the capability to simultaneously model multiple irrigation systems within the cropping systems model CropSyst.Task 1.3: Integrate the updated field-scale CropSyst model into the regional-scale VIC-CropSyst model to characterize historical and future agricultural water demands and to quantify changes to the two agroecosystem services of interest (Objectives 2 and 3).Objective 2: Comprehensively characterize current and future agricultural water demands (with and without adaptation), and quantify associated uncertainties.We will characterize historical (1980-current) and future (2040s, 2060s, 2080s) agricultural demands using the updated VIC-CropSyst model from Task 1.3. While the historical simulations represent current practices, future scenarios will be simulated with and without adaptation considerations that mitigate evaporative cooling needs or allow reallocation of water to address increasing needs. Current practices will also represent the "without adaptation" future scenarios. We will then select adaptation strategies during our stakeholder engagement process (see Objective 4), and represent those in the "with adaptation" future scenarios.Task 2.1: Prepare historical and future meteorological data and other inputs.Task 2.2: Perform VIC-CropSyst model simulations based on historical and future climate scenarios to quantify agricultural water demands (from both crop evapotranspiration and extreme heat management).Task 2.3: Perform a hybrid local-global sensitivity analysis to quantify uncertainty bounds for agricultural water demand projections stemming from the new FST submodel.Objective 3: Quantify changes (with and without adaptation) to two agroecosystem services -- timing and magnitude of water availability for crop production and for environmental flows --as a result of future changes in water supply and demands.To quantify agroecosystem services, the different demand estimates from Objective 2 need to be evaluated in conjunction with supply, which is also changing with changes in climate. Therefore, information from all the components in the integrated modeling framework will be utilized in this objective.Task 3.1: Develop time series of historical and future water supply at stream locations with minimum instream flow requirements.Task 3.2: Quantify the system's ability to meet two agroecosystem services (water for agricultural production and environmental flows) under historical and future scenarios.Task 3.3: Quantify the revised future ability to meet the two agroecosystem services by simulating the adaptation pathways identified in Objective 4 Tasks 4.1 and 4.2., and -- where they exist -- identify win-win opportunities for agriculture and the environment.Objective 4: (a) Co-identify, with stakeholders, adaptation alternatives that minimize negative impacts to agroecosystem services and enhance irrigated agroecosystem sustainability and (b) co-develop a path to integrate project findings into regional planning.This objective has two purposes. First, to elicit potential adaptation pathways that can be simulated to evaluate potential benefits to the two agroecosystem services, and ensure that the simulated adaptation pathways are currently feasible or considered good candidates to achieve those benefits (Tasks 4.1 and 4.2). We expect many of the potential adaptation pathways will require implementation by growers, but plan to also explore options that may be of particular interest to instream flow stakeholders due to expected benefits to flows. Second, this objective is designed to build awareness of this work among those whose actions our results can inform, including growers and the Washington Departments of Ecology, Fish and Wildlife, and Agriculture (Task 4.3).Task 4.1: Catalog adaptation pathways addressing negative impacts.In a workshop setting at the beginning of year 2, we will separately convene 6-10 agricultural and instream flow stakeholders with knowledge of both well-established and innovative or emerging strategies being used or tested that reduce the impacts of heat, reduce water use or reallocate water. Workshop participants will include both our project advisors and additional innovators they recommend. Through facilitated individual and group activities, we will elicit a list of potential strategies to adapt to changing climate stressors without negatively impacting the two agricultural and environmental agroecosystem services. Based on prior communications with stakeholders, we expect the list to include strategies such as changes in the crop mix, variety selection (some varieties are less susceptible to sunburn than others), changes in irrigation extent, precision evaporative cooling, and market-based approaches such as temporary water rights leasing (including subseasonal leasing). The list of strategies will be discussed and explored for socio-economic and practical adoptability, developing the team's understanding of what might facilitate or impede adoption.Task 4.2: Select promising adaptation pathways based on their potential for adoption or their potential for agroecosystem services benefits.Some of the potential adaptation strategies listed during the workshop may be more feasible than others, which will affect their future adoption. We will therefore seek input from a broad group of agricultural stakeholders (who are most likely the ones that would implement such strategies) as we select from the list of strategies developed in Task 4.1. We will participate in annual grower group meetings that have 1000s of participants (e.g. Annual Tree Fruit Meeting), and present and discuss extreme weather issues and the list of potential adaptation strategies. During the meeting, we will utilize a synchronous online questionnaire to elicit individual input on which adaptation strategies participants consider more or less feasible (with opportunities to indicate the reasons why). Both quantitative (Likert scale of how feasible) and qualitative responses (their reasoning for considering/not considering specific adaptation strategies) will be used.We will use the input on feasibility, recommendations from our advisory group, and our knowledge of research gaps or potential for innovation to select four adaptation strategies or combinations that will be prioritized for simulations (see Tasks 2.2 and 3.3, above). These choices may be watershed-specific.Task 4.3: Integrate research findings into ongoing collaborations that provide water supply and demand projections to Washington state agencies.