Applied Research

This project is no longer active.

Water is vital to ecological and human systems throughout the world. In the Pacific Northwest (PNW), the quantity, quality and timing of water resources has important implications for municipalities, agriculture, and ecology. How future changes in precipitation will impact water quality and quantity is an ongoing concern in the PNW. Watersheds rely on snowpack for water supply during drier months, so changes in the rain-to-snow ratio will impact water resources. Also, variability in heavy precipitation events affects the frequency of combined sewer overflow events in Portland and high turbidity in waterways, leading to a range of impacts for planners and managers. Collaborative work with Portland Water Bureau, Clackamas River Water Providers, Bureau of Environmental Services, and Water Environment Services addresses these concerns by utilizing observations and climate models to identify mechanisms associated with historical events and analyze projected changes in these features at a local scale.

For more information on Phase 1 of the interdisciplinary research conducted for Clackamas Watershed, see the following Report:

Left: Climatology of wet day precipitation (>0 mm) in Portland, OR with left y-axis corresponding to the average fraction of wet days per month (bars), and the right y-axis indicating the average wet day precipitation accumulation amount per month (blue line). Center: Climatology of heavy precipitation events (>90th percentile 1-day precipitation total) in Portland, OR with left y-axis indicating the average fraction of heavy total days per month (bars), and the right y-axis indicating the average event magnitude (blue line). Right: Average daily precipitation over the Pacific Northwest when there is a heavy precipitation event in Portland, OR (green circle).
CMIP5 multimodel annual mean temperature (left) and annual accumulated precipitation (right) averaged over the Clackamas Watershed for water years 1950-2099. Historical values are in green, and projected values under two climate change scenarios (RCP4.5 and RCP8.5) are depicted in gold and magenta. Lines correspond to the median across models, and shading indicates the envelope of all models used in the MACA dataset for ensemble r1i1p1 (for data information, see http://www.climatologylab.org/maca.html).

Presentations

"Projections of Future Large-Scale Weather Patterns, Temperature, and Precipitation over the Pacific Northwest," Northwest Climate Conference, Remote, April, 2021 (talk by Graham Taylor).

"Projections of Future Large-Scale Meteorological Patterns, Temperature, and Precipitation over the Pacific Northwest," American Geophysical Union Fall Conference, Remote, December, 2020 (poster by Graham Taylor).

"Assessing Weather Patterns Associated with Precipitation Extremes over Bull Run Reservoir," Northwest Climate Conference, Portland, Oregon, October, 2019 (poster by Graham Taylor).

"A Synoptic Approach to Studying Snow Drought in Oregon's Clackamas River Watershed in Observations and Climate Models," American Meteorological Society Annual Meeting, Phoenix, AZ, January, 2019 (talk by Arielle Catalano).

"Large-Scale Meteorological Patterns Associated with Precipitation Extremes Over Portland, Oregon, in Climate Models," American Meteorological Society Annual Meeting, Phoenix, AZ, January, 2019 (talk by Christina Aragon).

"Using Cluster Analysis to Study SWE Variability," American Geophysical Union Fall Meeting, Washington, DC, December, 2018 (poster by Shannon Kelly).

"Large-Scale Meteorological Patterns Associated with Heavy Precipitation and Storm Water Impacts in Portland, Oregon in Observations and Climate Models", Northwest Climate Conference, Boise, Idaho, October, 2018 (talk by Paul Loikith).

"Characterizing the Drivers of Extreme Changes in Watershed-Scale SWE in the Context of Climate Change," Northwest Climate Conference, Boise, Idaho, October, 2018 (talk by Christina Aragon).

"Towards Understanding the Impact of Climate Change on Water Quality and Quantity in Oregon's Clackamas River Watershed," Northwest Climate Conference, Boise, Idaho, October, 2018 (talk by Arielle Catalano).

"Large-Scale Meteorological Patterns Associated with Precipitation Extremes over Portland, OR," 8th GEWEX Open Science Conference: Extremes and water on the edge, Canmore, Alberta, Canada, May, 2018 (poster by Christina Aragon).

"Large-Scale Meteorological Patterns Associated with Extreme Precipitation Events over Portland, OR," American Geophysical Union Fall Meeting, New Orleans, Louisiana, December, 2017 (poster by Christina Aragon).

Publications

Catalano, A., P. C. Loikith, and C. Aragon, 2019: Spatiotemporal variability of 21st-century changes in site-specific snowfall frequency over the Northwest United States. Geophys. Res. Lett., 46, 10122-10131. AGU Link PDX Scholar Link

Aragon, C., P. C. Loikith, N. McCullar, and A. Mandilag, 2020: Large Scale Meteorological Patterns Associated with Extreme Precipitation Events over Portland, OR. Int. J. Climatol., https://doi.org/10.1002/joc.6487. RMetS Link

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