Originally published in our May 2020 newsletter (Issue 4)
I came to the United States to join PNNL in 2016. In my earlier research years, I immersed myself in water reservoir system planning and management, starting with utility company placements in the UK and Australia, then turning fully to academia with a postdoc in Singapore. Understanding how to simulate a reservoir has turned out to be a remarkably productive skill—one that’s applicable across a range of multisectoral research activities.
My research has branched out into three broad categories. First, if you can model reservoirs, you can simulate hydropower generation. And if you can project change in hydropower generation, you can start to investigate secondary effects on power grids—including impacts to production costs, future investment needs, emissions, and reliability of electricity supply. We’ve studied these effects at range of spatial scales (global, western power grid, Pacific Northwest, Texas) and using a variety of tools, including capacity expansion models, integrated assessment models, and production cost models.
Second, if you can model surface water reservoirs, you can also capture a lot of the basics of groundwater storage—enough to develop a simple water supply component for an Integrated Assessment Model. Using the Global Change Assessment Model with nonrenewable water embedded, we projected groundwater depletion across the world’s major river basins, and then studied the impacts on agricultural land use. We found that the increasing costs of water extraction in heavily exploited basins could cause marked regional shifts in the mode and locations of crop growth across the world this century.
Third, reservoir models are an increasingly important component of large-scale hydrological and water resource models. These models—initially conceived for earth systems research—are increasingly expected to inform MSD research applications, and thus require refinement and enhancement to capture important local nuances, such as the use of seasonal forecasting in reservoir management. We’ve been experimenting with new methods for simulating reservoir operator behaviors at a large scale; current results provide some hope that we might ultimately enhance simulation performance under extreme hydrological conditions, such as flood and drought. Capturing these effects will be essential for later propagating realistic water availability scenarios to energy and land impact models.
A final research activity I’ve been involved in is the collection and processing of dozens of geospatial datasets describing land, energy, water, and economic systems throughout the United States. By masking these data to the water supply catchments serving major US cities, we’ve begun to characterize and categorize cities according to their distal connections across sectors. Although at an early stage, this research is envisioned as a key capability that can inform the selection of case study cities for ongoing MSD projects.
Highlighted articles:
– Turner, S. W. et al., (2020) Inferred inflow forecast horizons guiding reservoir release decisions across the United States, Hydrol. Earth Syst. Sci., 24, 1275–1291
– Turner, S. W. et al. (2019). Compound climate events transform electrical power shortfall risk in the Pacific Northwest. Nature communications, 10(1), pp.1-8.
– Turner, S. W. et al. (2019). A pathway of global food supply adaptation in a world with increasingly constrained groundwater. Science of the total environment, 673, pp.165-176.