Research outputs
Explore selected scientific discoveries from the RHyCAM Lab, highlighting advances in hydroclimate science, Earth system modeling, and infrastructure resilience
Research highlights
A selection of findings from our research, explained in plain language. These are curated highlights, not the complete publication record.
The strongest winter storms in the western U.S. could bring up to 40% more precipitation at storm centers by mid-century. Understanding these changes is important for assessing future storm risks and improving infrastructure planning.
Machine-learning clustering identifies distinct weather and moisture conditions associated with wildfires in the western U.S., improving seasonal predictions by 10%. Historically, some wildfire types have grown more common while those associated with wetter soils have declined, revealing changing patterns of wildfire risk.
WAC-hydro classifies daily weather into 12 types based on precipitation and temperature, connecting large-scale climate variability to snowpack, runoff, and floods in the Pacific Northwest. The framework identifies weather patterns that elevate flood risk through heavy rainfall, snowmelt, or both.
Warmer coastal ocean temperatures bring wetter, warmer winters to the U.S. West Coast, reducing snowpack in the northern Cascades while increasing it in the southern Sierra Nevada. Changes in atmospheric rivers and precipitation interact with elevation to produce these contrasting responses.
Warmer coastal ocean temperatures strengthen landfalling atmospheric rivers along the U.S. West Coast, increasing their frequency, intensity, and spatial extent. Numerical experiments show that AR-related extreme precipitation increases by approximately 3% per degree of ocean warming, highlighting the influence of local sea surface temperatures on regional rainfall extremes.
A new precipitation-and-snow (PAS) framework identifies five event types, revealing that 50–90% of rainfall events involve snowpack changes across the western U.S. Snow accumulation is widespread, while melting is more common in coastal mountains, where relatively rare atmospheric rivers can drive substantial snowmelt during heavy rainfall.
Atmospheric rivers reshape western U.S. watershed hydrology by bringing heavy precipitation, reducing evaporation, and accelerating snowmelt through warmer temperatures and increased radiative heating. In some watersheds, they double runoff and account for 30–60% of annual streamflow variations, amplifying seasonal contrasts in regional water availability.
See Featured in AGU EOS by Minghua Zhang, DOE highlight, PNNL highlight
Atmospheric river occurrence, intensity, and duration help predict extreme precipitation in western U.S. watersheds at daily and monthly timescales. Machine-learning analysis highlights the importance of intense, long-lasting events, with stronger atmospheric rivers generally associated with heavier precipitation.
See DOE highlight
