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Title	Date	Authors	Abstract	URL
Decelerating Response of Western US Runoff to Shrinking Snowpacks	2025-05-16	Ban et al.	Climate warming threatens snowmelt‐derived water supplies in the western US (WUS) by reducing snowfall and snowmelt runoff, yet future rates of these declines remain highly uncertain in an evolving climate. Here, we analyze historical data, land surface model warming experiments, and climate projections across three major WUS river basins. We find that runoff loss become less sensitive to warming as snowpack shrinks, stemming from reduced snowmelt‐radiation feedback, a consequence of smaller snow‐cover changes and shifts in snowmelt timing to lower‐energy periods. Near‐linear projected warming with time (IPCC SSP245) exhibit a stable, possibly decelerating decline in runoff ratios. Although decelerating runoff declines do not eliminate broader water‐management challenges under continued warming, our findings complement the view that snowmelt‐radiation feedback drives runoff decline by highlighting the negative feedback from a shrinking snowpack on runoff warming sensitivity. Our findings should facilitate more comprehensive future water supply assessments in snow‐affected regions.	https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2025GL114629
Multidecadal drought impacts on the Lower Colorado Basin with implications for future management	2025-03-18	Scanlon et al.		https://www.nature.com/articles/s43247-025-02149-9
An Assessment of Potential Severe Droughts in the Colorado River Basin	2022-09-15	Salehabadi et al.	Much has been learned about Colorado River hydrology since the severe sustained drought study in 1995. We summarize our updated understanding of plausible future drought conditions by considering historical flows, tree-ring reconstructions, and climate change. We focus on natural streamflow at Lees Ferry, the primary metric used to quantify the runoff in the Colorado River Basin. We identify drought periods using historical records and tree-ring reconstructed streamflow at Lees Ferry, which we then use to characterize potential future droughts. Resampling from past drought periods generates plausible future conditions to consider during planning. We produced three drought scenarios, each comprising 100 streamflow sequences to be used as input to systems operation and management models. We used analysis of the duration-severity and cumulative deficit relative to the mean natural flow to evaluate droughts and drought simulations and show that the current millennium drought that started in 2000 has an average flow far less than the historical record. However, the flows reconstructed from tree rings or future flows projected from climate models indicate that even more severe droughts are possible. When used as input to the Colorado River Simulation System the drought scenarios developed indicate considerable periods when Lake Powell falls below its hydropower penstocks, indicating a need to rethink management and operation of these reservoirs during these critical conditions.	https://onlinelibrary.wiley.com/doi/10.1111/1752-1688.13061
What will it take to stabilize the Colorado River?	2022-07-22	Wheeler et al.	A continuation of the current 23-year-long drought will require difficult decisions to prevent further decline , The Colorado River supplies water to more than 40 million inhabitants in the southwestern United States and northwestern Mexico. A basin-wide water supply crisis is occurring because of decreased watershed runoff caused by a warming climate and legal and water management policies that allow systematic overuse. By the end of 2022, combined storage in Lake Powell and Lake Mead, the two largest reservoirs in the United States, will have declined from 95% full in 2000 to approximately 25% full. If this “Millennium Drought” persists, then stabilizing reservoir levels to avoid severe outcomes will require reducing water use to match diminished runoff. With a process underway to renegotiate interstate and international agreements on consumptive uses of the river, we describe a promising new management approach based on combined storage of both reservoirs, rather than just Lake Mead as currently used, to trigger consumptive use reductions to the Lower Basin and Mexico.	https://www.science.org/doi/10.1126/science.abo4452
Managing Colorado River risk	2021-05-28	Fleck and Udall		https://www.sciencemag.org/lookup/doi/10.1126/science.abj5498
Alternative Management Paradigms for the Future of the Colorado and Green Rivers	2021	Wheeler et al.
The future hydrology of the Colorado River Basin	December 2020	Salehabadi et al.		https://www.fs.usda.gov/rm/pubs_journals/2020/rmrs_2020_salehabadi_h001.pdf
Climate change and the aridification of North America	2020-06-02	Overpeck and Udall		http://www.pnas.org/lookup/doi/10.1073/pnas.2006323117
On the causes of declining Colorado River streamflows	09/2018	Xiao et al.		http://doi.wiley.com/10.1029/2018WR023153
Fourth National Climate Assessment-Chapter 25: Southwest	2018	Gonzalez et al.	This report is an authoritative assessment of the science of climate change, with a focus on the United States. It represents the second of two volumes of the Fourth National Climate Assessment, mandated by the Global Change Research Act of 1990.	https://nca2018.globalchange.govhttps://nca2018.globalchange.gov/chapter/25
The twenty-first century Colorado River hot drought and implications for the future	03/2017	Udall and Overpeck	Between 2000 and 2014, annual Colorado River flows averaged 19% below the 1906–1999 average, the worst 15-year drought on record. At least one-sixth to one-half (average at one-third) of this loss is due to unprecedented temperatures (0.98C above the 1906–1999 average), confirming model-based analysis that continued warming will likely further reduce flows. Whereas it is virtually certain that warming will continue with additional emissions of greenhouse gases to the atmosphere, there has been no observed trend toward greater precipitation in the Colorado Basin, nor are climate models in agreement that there should be a trend. Moreover, there is a significant risk of decadal and multidecadal drought in the coming century, indicating that any increase in mean precipitation will likely be offset during periods of prolonged drought. Recently published estimates of Colorado River flow sensitivity to temperature combined with a large number of recent climate model-based temperature projections indicate that continued business-as-usual warming will drive temperature-induced declines in river flow, conservatively 220% by midcentury and 235% by end-century, with support for losses exceeding 230% at midcentury and 255% at end-century. Precipitation increases may moderate these declines somewhat, but to date no such increases are evident and there is no model agreement on future precipitation changes. These results, combined with the increasing likelihood of prolonged drought in the river basin, suggest that future climate change impacts on the Colorado River flows will be much more serious than currently assumed, especially if substantial reductions in greenhouse gas emissions do not occur.	http://doi.wiley.com/10.1002/2016WR019638
Understanding Uncertainties in Future Colorado River Streamflow	01/2014	Vano et al.		http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-12-00228.1
Combined impacts of current and future dust deposition and regional warming on Colorado River Basin snow dynamics and hydrology	2013-11-07	Deems et al.		https://www.hydrol-earth-syst-sci.net/17/4401/2013/
Response of Colorado River runoff to dust radiative forcing in snow	2010-10-05	Painter et al.		http://www.pnas.org/cgi/doi/10.1073/pnas.0913139107
Rethinking vulnerability on the Colorado River	03/2010	Kenney et al.	On the Colorado River (as elsewhere), severe drought is useful for illuminating sources of water supply vulnerability, focusing attention on deficiencies in water allocation and management. A major drought study in the early 1990s, and experience with real drought a decade later, both have been useful in understanding vulnerability as a function of several factors working in consort with drought, including water allocation, reservoir operations, water demands, and climate change. Over this relatively short time-frame, vulnerability has shifted considerably, and will undoubtedly continue to change further in coming decades. Understanding how vulnerability is shifting is central to identifying future management pathways and reform options for the river.	http://doi.wiley.com/10.1111/j.1936-704X.2010.00068.x
Water supply risk on the Colorado River: Can management mitigate?	08/2009	Rajagopalan et al.		http://doi.wiley.com/10.1029/2008WR007652
Climate Change in Colorado: A Synthesis to Support Water Resources Management and Adaptation	2008	Ray et al.		https://wwa.colorado.edu/publications/reports/WWA_ClimateChangeColoradoReport_2008.pdf
Udall and Overpeck - 2017 - The twenty-first century Colorado River hot drough.pdf
Overpeck and Udall - 2020 - Climate change and the aridification of North Amer.pdf
Fleck and Udall - 2021 - Managing Colorado River risk.pdf				https://science.sciencemag.org/content/sci/372/6545/885.full.pdf