The Science

Researchers developed a new statistical framework to assess changes in climatic conditions using data from 1966 to 2021 from 17 meteorological stations across the East River watershed near Crested Butte, Colo., which is a typical watershed in the Upper Colorado River Basin providing freshwater to millions of Americans. Grouping similar watershed areas into zones using hierarchical clustering of site locations for three temporal segments of the Standardized Precipitation-Evapotranspiration Index (SPEI) showed significant temporal-spatial shifts, indicating that dynamic climatic processes drive zonation patterns.

The Impact

Mountainous watersheds provide 60–80% of Earth’s freshwater in addition to other life-sustaining ecosystem services, such as air and water quality regulation and carbon sequestration. Analyzing long-term spatial and temporal climate data in these important regions can help scientists understand how these critical ecosystems may respond, or are already responding, to changing climate. Scientists developed a statistical framework to assess changes in climatic conditions in Colorado’s East River Watershed. The assessment indicates considerable changes in climatic conditions with time and space, demonstrating that not only is climate change affecting the watershed, but different zones are responding in different ways. Understanding these changes can help researchers predict and monitor how the ecosystems, in addition to services they provide, may change to better adapt to climate change.

Summary

Researchers developed a statistical framework to assess long-term temporal and spatial variability of meteorological conditions including temperature, dewpoint, precipitation, relative humidity, and wind speed, as well as time series of potential and actual evapotranspiration, Standardized Precipitation Index, and SPEI. Calculations were conducted from 1966 to 2021 for 17 locations of meteorological stations located within the East River watershed in Colorado. Time series segmentation analysis and zonation demonstrate considerable changes in climatic conditions with a non-uniform response across the watershed. A significant shift in cluster arrangements for the temporal segments indicates that zonation patterns are driven by dynamic climatic processes, which are variable through time and space. Therefore, the watershed climatic zonation requires periodic re-evaluation based on climatic changes with space and time.

Principal Investigator

Boris Faybishenko
Lawrence Berkeley National Laboratory
bafaybishenko@lbl.gov

Co-Principal Investigator

Eoin Brodie
Lawrence Berkeley National Laboratory
elbrodie@lbl.gov

Program Manager

Jennifer Arrigo
U.S. Department of Energy, Biological and Environmental Research (SC-33)
Environmental System Science
jennifer.arrigo@science.doe.gov

Funding

The work was conducted as part of the Watershed Function Science Focus Area at Lawrence Berkeley National Laboratory, which is supported by the Biological and Environmental Research Program within the U.S. Department of Energy’s (DOE) Office of Science under Contract Number DE-AC02-05CH11231.

References