U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights

Tethys Tackles Downscaling Challenge for Regional Water Withdrawals
Published: February 09, 2018
Posted: July 30, 2018

A new open-source tool helps connect high-resolution sectoral models and broader integrated human-Earth system models.

The Science
Downscaling of water withdrawals is a fundamental step when integrating large-scale complex human-Earth models with detailed sectoral models. Researchers at the U.S. Department of Energy’s Pacific Northwest National Laboratory and the University of Maryland, College Park, developed Tethys, an open-access software package that applies statistical algorithms to spatially and temporally downscaled water withdrawal data.

The Impact
Tethys bridges the gap between coarser integrated human-Earth system model projections and detailed sectoral models that require high-resolution water withdrawal projections in space and time. The ability to exchange water withdrawal information when coupling models of different scales is especially important to inform local and regional water resource projections and planning.

Researchers developed Tethys to produce monthly, gridded global water withdrawal data products based on estimates from the Global Change Assessment Model (GCAM), an integrated human-Earth system model. GCAM is often coupled to sectoral models that typically operate at finer scales, and mismatches across time and space can occur. Tethys eliminates such mismatches by using statistical algorithms to downscale global water withdrawal data. Researchers first separated water withdrawals into six common high-volume water-use sectors: irrigation, livestock, domestic, electricity generation, manufacturing, and mining. They then derived downscaling algorithms parameterized using collected data products and applied them to the various sectors. These algorithms downscaled the spatial resolution from region/basin scale to grid (0.5 geographic degree) scale and the time resolution from year to month.


Bob Vallario
Multisector Dynamics Research

(PNNL Contact)
Mohamad Hejazi
Pacific Northwest National Laboratory

The U.S. Department of Energy Office of Science supported this research through the Multi-Sector Dynamics, Earth and Environmental System Modeling Program.

Li, X., C.R. Vernon, M.I. Hejazi, R.P. Link, Z. Huang, L. Liu, L. Feng. “Tethys — A Python Package for Spatial and Temporal Downscaling of Global Water Withdrawals.” Journal of Open Research Software 6(1), 9 (2018). [DOI: 10.5334/jors.197]

Related Links
Journal Article

Topic Areas:

  • Research Area: Earth and Environmental Systems Modeling
  • Research Area: Multisector Dynamics (formerly Integrated Assessment)

Division: SC-23.1 Climate and Environmental Sciences Division, BER


BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

May 10, 2019
Quantifying Decision Uncertainty in Water Management via a Coupled Agent-Based Model
Considering risk perception can improve the representation of human decision-making processes in age [more...]

May 09, 2019
Projecting Global Urban Area Growth Through 2100 Based on Historical Time Series Data and Future Scenarios
Study provides country-specific urban area growth models and the first dataset on country-level urba [more...]

May 05, 2019
Calibrating Building Energy Demand Models to Refine Long-Term Energy Planning
A new, flexible calibration approach improved model accuracy in capturing year-to-year changes in bu [more...]

May 03, 2019
Calibration and Uncertainty Analysis of Demeter for Better Downscaling of Global Land Use and Land Cover Projections
Researchers improved the Demeter model’s performance by calibrating key parameters and establi [more...]

Apr 22, 2019
Representation of U.S. Warm Temperature Extremes in Global Climate Model Ensembles
Representation of warm temperature events varies considerably among global climate models, which has [more...]

List all highlights (possible long download time)