Human water withdrawal is shown to alter the global water cycle, yet our understanding of its driving forces and patterns is limited primarily to water withdrawal estimates available at annual and country scales. Researchers at the U.S. Department of Energy’s Pacific Northwest National Laboratory reconstructed a global monthly, gridded (0.5 degree), sectoral water withdrawal dataset for the period 1971–2010, that distinguishes six water use sectors: irrigation, domestic, electricity generation (cooling of thermal power plants), livestock, mining, and manufacturing. The gridded dataset constitutes the first reconstructed global water withdrawal data product at seasonal and regional resolution that is derived from different models and data sources.
The reconstructed gridded water withdrawal dataset is open-access, and can be used to compare water withdrawal estimates from global hydrologic models and also to supplement water withdrawal estimates in Earth system models, where domestic and industrial water withdrawal representations are often lacking. The dataset is also important for investigating water-use related issues and patterns at fine spatial, temporal, and sectoral scales, which is critical for developing sound water management strategies.
Information on human water use is often available only on large space and time scales. To better inform Earth system models and global hydrologic models, the research team created estimates of water withdrawals on a smaller scale. They divided the Earth’s surface into areas 0.5° by 0.5° (about 50 kilometers [30 miles] square near the equator), and combined the larger-scale data on water use with records of population, temperature, power usage, agriculture, manufacturing, and mining. They used several models to estimate water use in each of the grid areas, and verified their estimates with historical records between 1971–2010. The dataset will be useful for water management and for Earth system modeling.