Completed Research Projects

Below are descriptions of selected WWA research projects, and their deliverables. For a complete list of projects and other activities conducted each year, see the WWA Annual Reports.

Adapting Stormwater Infrastructure to Extreme Precipitation

Primary Investigators: W. Travis, A. McCurdy, I. Rangwala
Stakeholders: Stormwater managers

Increases in precipitation intensity raise the question of how to adapt stormwater infrastructure. We developed a model to simulate the effects of increasing flows on roadway culverts, which are typically constructed to convey certain flow volumes. Key model inputs include when and how to modify stormwater infrastructure as climate changes and culvert failures become more likely. By the end of this reporting period WWA Graduate Student Adam McCurdy successfully produced several adaptation simulations using the model for a testbed of selected Colorado culvert emplacements. McCurdy presented on the results at the Adaptation Futures conference in May, 2016 in Rotterdam, Netherlands.  That presentation and two articles prepared for submission, available as working papers in the WWA website, convey the key findings related to different rates of climate change and four different adaptation strategies: Nominal, Anticipatory, Reactive, and Concurrent. The Nominal Strategy assumes no change in culvert replacement strategy over the entire simulation; in the event that a crossing’s lifespan is reached, or the crossing is destroyed by a runoff event, it is replaced with a crossing of the same capacity. Under the Anticipatory Strategy, all crossings are replaced with higher capacity crossings prior to the end of their normal lifespans. Under the Concurrent Strategy the capacity of each crossing is increased at the time of normal replacement. The Reactive Strategy begins with the Nominal Strategy and switches to the Concurrent Strategy when a crossing is replaced following damage by an extreme event. Results indicate that aggressive anticipatory replacement of culverts is economically inefficient even under rather large climate change scenarios. This is due to the sunk investment of culverts and the traffic disruption caused by construction. The most efficient adaptation pathway under climate uncertainty appears to be to invest more effort to evaluate the vulnerability of each culvert no matter what its life-cycle status, and adapt only those likely to failure in the near term.

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Analysis of Use of Information by Stakeholders of the Colorado Basin River Forecast Center

Primary Investigators: L. Dilling, R. Klein
Stakeholder: NOAA NWS Colorado Basin River Forecast Center

Effort to understand the flow of forecast information to stakeholders of the NOAA Colorado Basin River Forecast Center

The Colorado Basin River Forecast Center (CBRFC) generates forecasts across the Colorado Basin and Utah including daily streamflow forecasts, long lead peak flow forecasts and water supply forecasts. Decision makers such as Denver Water, the Bureau of Reclamation, the Central Arizona Project, and the Colorado River District are some of the CBRFC stakeholders who use or potentially might use these forecasts. Previous research has found, however, that unless reliability and/or quality are threatened, water management agencies have little incentive to use forecasts (especially ensemble forecasts), and that forecast use correlates more with perceived risk than with forecast skill and reliability. A series of workshops with CBRFC stakeholders (facilitated through a previous WWA-CLIMAS project) assessed individual decisionmaking processes in order to see how stakeholders processed visual representations of streamflow data and forecasts and then used this information in decisionmaking. One of the conclusions from the workshops was that a better understanding of the decision making process was needed (Werner et al. 2011). The Deems et al. “Snowmelt Perturbations” project falls within the research and operations part of the framework in that it is working to improve tools such as CBRFC forecasts. This project will augment the snowmelt research by obtaining a better understanding of both the CBRFC stakeholder decision making process as well as how WWA research can feed into this process. We will provide basic data on the stakeholders of the CBFRC, their climate-related decision making contexts, and the role that information does and could play. We also will analyze the potential for the WWA snowpack physical science research to be usable in the CBFRC context and how such information can help stakeholders make better decisions. PIs are preparing a summary and analysis of the interviews which will be integrated with the survey results into a final white paper that will be shared with CBRFC and posted on the WWA website.

Deliverables: Initial survey results presented to CBRFC; White paper forthcoming.

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Analyzing Expressed Stakeholder Needs in the Western Water Assessment Region

Primary Investigators: Lisa Dilling, John Berggren

Systematic examination of stakeholder needs for climate information through previous documentation, in order to avoid replicating previous efforts and exacerbating stakeholder fatigue

Through web-based searches and querying a network of key informants and collaborators, WWA researchers Dilling and Berggren developed a list of documents to include in a database of expressed stakeholder needs for climate information. Documents were included if they identified any type of stakeholder need regarding climate information, and were within the WWA’s geographic scope. Needs that were repeatedly mentioned were additional monitoring such as USGS stream gauges and NRCS SNOTEL sites, better communication and collaboration between scientists/researchers and stakeholders, and a ‘clearinghouse’ or ‘portal’ where stakeholders could easily obtain climate-related information. The documents also suggested that current management and research are addressing the appropriate issues, but could be better coordinated and communicated to improve decision-making. Additional climate and hydrologic monitoring and modeling would better assist managers and planners, but only if the data is readily available and in a useful form. The PIs are currently in the process of producing a white paper and writing an article for submission in a peer-review journal.  Two other RISAs (Great Lakes Integrated Sciences and Assessments, and Carolinas Integrated Sciences and Assessments) conducted similar stakeholder needs analyses, and the resulting comparative framework will be published in the near future.

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Assessment of Documented Needs for Climate Information in the Missouri River Basin

Principal Investigators: Kristen Averyt, Eric Gordon
Other Researchers: John Berggren, Doug Kluck (NOAA)

Final Project Report
Initial assessment of Missouri Basin stakeholder needs for information on impacts of climate variability and change

By providing a broad overview of needs in the Missouri Basin, this effort can help guide federal investments in climate services for the basin by providing a blueprint for where services are needed the most. The examination of stakeholder needs involves developing a comprehensive list of documents where stakeholders have expressed the need for climate information within the Missouri River Basin, followed by a set of key stakeholder interviews aimed at filling in the gaps from the initial document review. Rather than beginning an assessment with the more traditional formal interview process, this project began with a systematic examination of stakeholder needs for climate information as demonstrated in existing documentation. (This method was used effectively in a previous project cataloging needs throughout the Western Water Assessment RISA region.) Reviewing previously published documents allows for the development of an understanding of baseline climate related needs over an extended time period.  Conducting this type of needs analysis prior to interviewing stakeholders also helps avoid fatigue among stakeholders, a recognized informal and formal impediment to engaging relevant stakeholders in developing necessary and applicable research portfolios. The output of this project is intended to inform future work by Doug Kluck, the NOAA Central Region Climate Services Director, in coordinating regional climate services.

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Boulder County Climate Change Preparedness Plan

Primary Investigators: Eric Gordon, Joe Barsugli

Development of policy-oriented climate change adaptation plan for Boulder County and the City of Boulder, Colorado

Climate change has the potential to exacerbate many of the challenges faced by Boulder County and its municipalities. These challenges include droughts, flash flooding, West Nile virus, heat waves, fire mitigation and fire protection, and increased road maintenance, among others. WWA, together with Stratus Consulting and AMEC Earth & Environmental, was awarded a contract to develop a climate change adaptation plan for the County of Boulder, Colorado and the municipalities contained within its borders. In addition to providing a needed service to the city and county where WWA is physically located, this project provided an opportunity for WWA to engage in on-the-ground adaptation planning efforts, and contribute to WWA broader efforts to understand and improve adaptation practices across the Intermountain West region. WWA’s specific contributions included drafting of a review of relevant science on climate projections and hydrologic impacts (Barsugli), drafting of a chapter on adaptation options for the water sector (Gordon) and co-authoring of the report’s introduction and conclusion (Gordon). The draft report was completed in December 2011 and a final version is expected to be approved by Boulder County Commissioners in 2012.

Papers, Reports, and Presentations for this Project
Draft Boulder County Climate Change Preparedness Plan

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Building Climate Science into Land and Water Conservation Planning and Decisionmaking in the American Southwest

Primary Investigators: W. Travis, I. Rangwala, J. Barsugli, G. Garfin (CLIMAS), E. Gordon
Stakeholders: The Nature Conservancy, others participating in Gunnison Basin conservation efforts Partners: The Nature Conservancy, DOI/USGS North Central Climate Science Center, CLIMAS RISA

Project funded by intra-RISA competition to pilot new efforts to integrate climate science into conservation adaptation efforts developed by The Nature Conservancy in the Southwest

Collaboration with Leveraged Project: Southwest Colorado Social Ecological Climate Resilience: The experience of the project personnel in the core effort helped Travis and Rangwala become part of a separate but linked DOI North Central CSC-funded project. Rangwala has been the lead climatologist on this project, which entails a collaboration among the Nature Conservancy (TNC) and its partners in the Gunnison Basin, San Juan Mountains and the Four Corners regions. He has developed landscape-scale climate scenarios from the CMIP5 global climate models for the region. These will be used by an ecologist and a social scientist, in conjunction with Rangwala, to develop narrative scenarios of future climate and its impacts. Next, the project scientists, in a collaborative process with land managers, will use these narrative scenarios to develop robust adaptation strategies that could work across these climate futures for a particular time horizon. Rangwala is developing “target-specific” climate scenarios for different systems targets selected in the project. This information will be collaboratively produced by integrating the expert and local knowledge of a specific target with the larger scale climate projections. It is expected that development of such information would be more actionable for the user community. Evaluate and improve methodologies for developing “actionable climate scenarios”: Rangwala has been working with Barsugli, Travis, Clifford, Betsy Neely (TNC), Renee Rondeau (Colorado Natural Heritage), Erin Towler (NCAR), Teresa Chapman (TNC), Laurie Young and Carina Wyborn (U. Montana), among others, to evaluate and improve the approach for developing more effective and actionable climate scenarios for resource management and conservation. Understanding local climate knowledge and its influence on decision making: Clifford designed a survey to probe local knowledge of climate and stakeholder climate information needs for application during a summer 2013 fieldwork season. The survey was approved by the university’s IRB for human subjects, and administered by Clifford in the field during July-August, 2013. Twenty-six of the 28 interviews were transcribed in their entirety using “intelligent verbatim” protocol to maintain the rich quality of each interview and correctly capture participants’ opinions and insights, while dispensing with non-essential words. These documents ranged from 1297 to 4310 words per interview transcript. Transcribed interviews were entered into the qualitative coding software, NVivo, and coded according hypotheses, interview topics and assumed themes. The a priori codes were built around the hypothesized structure of climate features, benchmarks and processes, that we expected interviewees to use when explaining experienced climate.

Deliverables: Direct guidance to TNC and its partners; AGU poster; K. Clifford Master’s Thesis
Leveraged Funding: $10,000 in travel and other support from TNC

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Climate adaptation for Western National Forests

Principal Investigator: Janine Rice
Other Researchers: Jeff Lukas, Linda Joyce (USDA Forest Service)

Conducting a pilot climate vulnerability assessment for the Shoshone National Forest as part of a broader effort by the US Forest Service to develop a climate adaptation toolkit

As part of a broader US Forest Service effort entitled “A Toolkit for Adapting to Climate Change on Western National Forests: Incorporating Climate into Resource Management and Planning,” WWA’s Rice has been worked with others at the Forest Service’s Rocky Mountain Research Station in Fort Collins, CO on a pilot climate vulnerability assessment for the Shoshone National Forest. In 2011, Rice completed a Forest Service General Technical Report entitled “Climate Change on the Shoshone National Forest, Wyoming: A Synthesis of Past Climate, Climate Projections, and Ecosystem Implications,” which synthesizing current scientific information about climate and its effects on ecosystem components of the Shoshone NF. Additional funding provided in 2012 will be used for completion and review of the climate vulnerability assessment and publication of technical reports on vulnerability assessment of vegetation, water availability, and coldwater fish habitat.

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Climate Adaptation Guidance for Salt Lake City Public Utilities

Primary Investigator: T. Bardsley
Stakeholder: Salt Lake City Department of Public Utilities
Partners: A. Wood (NCAR), L. Briefer (SLCPUD), J. Niermeyer (SLCPUD), M. Hobbins (NOAA ESRL PSD), S. Burian (University of Utah), E. Goharian (University of Utah), C. Strong (University of Utah), P. Stoker (University of Utah), J. Lhotak (NOAA CBRFC), C. Peterson (NOAA CBRFC)

Working with the Salt Lake City Department of Public Utilities (SLCDPU) to help them assess the challenges that climate change presents to their water supply system

WWA’s Tim Bardsley has spearheaded a climate change assessment and adaptation planning effort for the Salt Lake City Department of Public Utilities. The results of this first phase of work, consisting of a water supply climate sensitivity analysis, was published as “Planning for an Uncertain Future: Climate Change Sensitivity Assessment towards Adaptation Planning for Public Water Supply” in a special edition of Earth Interactions. This paper produced numerous media hits and was cited as a prime example of local-level adaptation work by the White House Office of Science and Technology Policy. Ongoing efforts in this project include a pilot study on one of Salt Lake City’s watershed creeks, where a reservoir systems planning model has been developed. The model has recently been expanded to include the full water supply system. This systems model is currently being incorporated into an integrated water planning model. The planning model will facilitate more comprehensive assessments of changes in system reliability are being evaluated in combination with future water demand, supply, infrastructure, and management scenarios. To add to available information on climate impacts to water supplies, Bardsley will work with colleagues to integrate soon-to-be-available high-resolution dynamically downscaled climate projections, test an expanded integrated water planning model, and develop more advanced water supply and demand scenarios to evaluate a range of possible future impacts to water supply to assist in defining low-regrets management strategies.

Bardsley, T., A. Wood, M. Hobbins, T. Kirkham, L. Briefer, J. Niermeyer, and S. Burian (2013). Planning for an Uncertain Future: Climate Change Sensitivity Assessment toward Adaptation Planning for Public Water Supply. Earth Interactions, Volume 17, Issue 23, 1-26, October, doi: 10.1175/2012EI000501.1

Multiple stakeholder presentations; information directly transferred to SLCDPU.

Leveraged Funding:
In-kind staff efforts from NOAA Colorado Basin River Forecast Center, University of Utah, National Center for Atmospheric Research, and NOAA Earth Systems Research Laboratory Physical Sciences Division

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Climate Change Impacts on Public Lands in the Upper Colorado River Basin

Primary Investigators: Jason Neff, Karen Cozzetto, Dan Fernandez

Development of a model, with managers at the BLM/USFS San Juan Public Lands Center, to understand the vulnerability of public lands to drought based on ecological and physical factors

This project entailed the development of a simple ecophysiological model to produce initial drought vulnerability mapping that could be used by land managers in climate change analysis and planning efforts. A model incorporating climate, soil, and vegetation was run with precipitation data from 1948–1998 to produce a vulnerability map representing plant communities, soil textures and depth, and precipitation gradients. In the model used, transpiration and precipitation were very strong predictors of drought vulnerability. However, for the model to be of greater value to land managers, it needs a second soil depth layer in order to capture the true difference between summer and winter precipitation.

Papers, Reports, and Presentations for this Project
Project summary white paper

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Climate Change Preparedness Among Tribal Communities in the American West

Principal Investigator: Karen Cozzetto
Other Researchers: Julie Nania, Julie Teel Simmonds

Project Deliverables
Technical Review of the Navajo Nation Drought Contingency Plan – Drought Monitoring

4th Annual Navajo Nation Agricultural Conference (April 25, 2013)

Building new stakeholder relationships with native communities and understanding tribes’ needs for relevant climate information and assistance to prepare for climate change

Many tribes in the Southwest face pressing challenges that would be exacerbated by a warming climate, including persistent drought and land-cover change, while socioeconomic and historical factors may limit their adaptive capacity. This project seeks to understand tribal efforts towards climate adaptation while bringing university-based resources to bear on those efforts. Completed work includes the “Native Communities and Climate Change” database available at and a culturally appropriate Tribal Energy Action and Climate Change Adaptation Reports in consultation with the Southern Ute Tribe and Navajo Nation in the Southwest. Ongoing work includes the development of relationships with tribal managers interested in drought mitigation, water conservation planning, or climate change information. The project will be completed in 2012 with a report on 1) how to transition knowledge and lessons learned to service partners and 2) the appropriate role of RISAs in addressing tribal issues within the region.

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Climate Related Decisionmaking on Public Lands in the Intermountain West

Primary Investigators: Lisa Dilling, Kelli Archie

Survey of public land managers in the Intermountain West to gauge their awareness of climate variability and change, and their willingness to incorporate climate information into planning

Despite agency-level efforts to promote climate adaptation on federal public lands, it is unclear how widespread adaptation efforts are on a regional or office basis. Previous research has showed that though there is strong climate change awareness among land managers, direct action addressing climate change is more limited. In order to obtain data about individual land manager and agency-level adaptation barriers and plans, PIs surveyed approximately 3100 land managers employed by the Bureau of Land Management, the US Forest Service, the National Park Service, and the US Fish and Wildlife Service in Colorado, Utah, and Wyoming. Results suggest that adaptation planning by public lands agencies in CO, UT and WY is occurring but that implementation of these plans remains relatively rare. In addition, individual beliefs and attitudes about climate change do not appear to influence responses about adaptation planning, although the agency for which a respondent works is a statistically significant predictor of respondents’ assessments of current adaptation planning.

Papers, Reports, and Presentations for this Project
Climate Change and Western Public Lands: a Survey of U.S. Federal Land Managers on the Status of Adaptation Efforts, Ecology and Society 17(4): 20.

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Climate Science Support for Vulnerability Assessment of the Gunnison Basin 

Primary Investigators: Joe Barsugli, Imtiaz Rangwala

Providing climate science support and guidance for a multi-stakeholder effort to assess climate change vulnerability in the Gunnison River Basin

In 2010 and 2011, WWA researchers Barsugli and Rangwala provided climate science support and guidance to a landscape-scale climate change vulnerability assessment effort led by The Nature Conservancy. This assessment was developed explicitly for the Gunnison Climate Working Group, a collaboration among public and private stakeholders interested in building ecosystem resilience in the basin. Barsugli’s efforts focused in particular on guiding the selection and use of climate models and relevant climate and hydrologic data used to determine the relative future vulnerability of 24 ecosystems in the Gunnison Basin. These efforts were detailed in a report (Neely et al. 2011) that will serve as the basis for future collaborative resilience management efforts and as a pilot for other landscape-scale assessments initiated by The Nature Conservancy.

Papers, Reports, and Presentations for this Project
Gunnison Basin Climate Change Vulnerability Assessment for the Gunnison Climate Working Group

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Colorado Climate Change Vulnerability Study

Primary Investigator: E. Gordon
Partner: D. Ojima (Colorado State University)
Stakeholders: Colorado Energy Office (CEO) and other Colorado state agencies

Overview of key climate-related vulnerabilities facing several sectors in the State of Colorado.

During its 2013 session, the Colorado Legislature passed HB 13-1293, which declared that “climate change presents serious, diverse, and ongoing issues for the state’s people, economy, and environment.” Among other provisions, the bill required a person appointed by the Governor to submit an annual report to a number of committees within the legislature “on climate change issues generally, the current climate action plan...and the specific ways in which climate change affects the state.” Multiple state agencies, including the Colorado Energy Office, the Colorado Department of Public Health and the Environment, and the Colorado Water Conservation Board are leading efforts to respond to this legislation and to meet the challenges of climate change in the state. To help meet this requirement, the Colorado Energy Office commissioned the University of Colorado Boulder (through the Western Water Assessment) and Colorado State University to complete a study providing an overview of the key vulnerabilities that climate change and climate vulnerability will pose for Colorado's economy and resources.

Deliverables: Final report delivered to CEO in July 2014; will be officially released in November 2014.

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Colorado Climate Preparedness Project

Primary Investigators: Roberta Klein , Eric Gordon, William Travis, Jeff Lukas, Kristen Averyt, Brad Udall

Preliminary assessment of climate impacts and adaptations relevant to state agencies in Colorado; development of an online adaptation database

At the request of the state of Colorado, WWA researchers conducted a preliminary assessment of climate impacts and adaptation options in five sectors—water; electricity; wildlife, ecosystems, and forests; agriculture; and outdoor recreation. The results of this effort are compiled in a database of people, projects, products, and organizations relevant to adaptation in the state and a final report. The report and the database are intended to help facilitate future vulnerability assessment and adaptation planning efforts across the state. The database code is being made available to other RISAs as needed and will be used in future WWA assessment work. The final report (Klein et al. 2011) was completed in early 2011 and presented to Governor Hickenlooper and his staff.

Papers, Reports, and Presentations for this Project
Colorado Climate Preparedness Project Final Report
Colorado Climate Preparedness Project Database

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Controls on pH and Ammonia Toxicity in Rivers of the Colorado Plains

Primary Investigators: James McCutchan, Suzanne van Drunick, Mary Huisenga

Development of a modeling framework to predict changes in water quality in response to climate variation or changes in water management

Temperature directly affects the numeric standards for ammonia in warm-water streams of Colorado, but temperature also can affect ammonia standards indirectly through interactions that link climate, metabolic processes, and pH. Recent monitoring data for rivers on the plains of Colorado, in combination with results of studies of oxygen metabolism, suggest that the balance between photosynthesis and respiration favors high pH when temperature is high. Samples and field measurements were collected between July 2010 and May 2011 at four stations, in order to determine the relative importance of temperature, hydrologic variables, and biomass of benthic algae in controlling pH in Plains streams and rivers. Across the sampling stations, biomass of benthic algae remained low when depth was greater than ~0.35 m; below this depth threshold, algal biomass was able to accumulate when other factors were not limiting to growth. For a given location, the depth threshold of ~0.35 m can be translated into a discharge threshold for removal of algal biomass, thus providing a basis for analysis of historical records or for modeling. The potential for metabolic control of pH is highest at low discharge and especially after extended periods of low discharge. Neural-network modeling showed, for a given location, a strong relationship between discharge and pH. Temperature, time of day, and recovery (time since a critical flow for removal of periphyton biomass) affect pH at low discharge, but not when discharge is high. Although additional field studies are needed to improve modeling accuracy, these relationships demonstrate strong potential for predictions of the effects of climate variation or changes in water management on pH in Plains rivers. Preliminary modeling suggests that climate warming may lead to a modest increase in pH for Plains rivers. The most important factors affecting pH, however, are related to hydrologic variation and changes in water management, both of which can affect the patterns of accumulation for periphyton biomass.

Papers, Reports, and Presentations for this Project
“Controls on pH and Ammonia Toxicity in Rivers of the Colorado Plains,” WWA White Paper.

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Cross-Jurisdictional Water Marketing

Principal Investigator: Douglas Kenney
Other Researchers: Julie Nania (University of Colorado School of Law)

Synthesis of lessons learned about interstate water marketing in the American West

Discussions about the possibility of cross-jurisdictional water marketing in the Colorado River Basin have resumed after breaking off in the 1990s. This project will examine what was learned during previous discussions and what is known about water markets to assess how this policy mechanism could improve adaptability.  It will also involve the development of a centralized database of federally reserved water rights for tribes, including compilation of information on whether tribes in the Colorado River basin have quantified rights and whether those rights can be marketed or leased.

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Decisionmaking Under Hydro-Climatic Uncertainty

Primary Investigator(s): W. Travis, M. Huisenga

Development of models and other tools capable of understanding how decision deal with hydro-climatic uncertainty in climate adaptation, including response to droughts

This project seeks to develop and apply decision analysis to adaptation of climate-sensitive activities in the WWA region. It fits in between vulnerability assessments and empirical studies of adaptation, providing a modeling “test bed” to develop hypothesis and test hypotheses about how decision makers might respond to climate variation and change in specific resource management systems. Particular attention is
given to adaptation decisions in response to extreme climate events. The project effort is guided by attention to decision analysis and decision support in the latest National Climate Assessment.

Deliverables: W.R. Travis and M. Huisenga (2013) The Effect of Rate of Change, Variability, and Extreme Events on the Pace of Adaptation to a Changing Climate. Climatic Change 121: 209–222. DOI 10.1007/s10584-013-0876-3

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Downscaled Temperature and Precipitation Projections for Southwestern Colorado

Primary Investigators: Imtiaz Rangwala, Karen Cozzetto, Jason Neff, Joe Barsugli

Analysis of downscaled climate projections for the San Juan Mountains to understand their accuracy at simulating temperature and precipitation patterns in the region

The project entailed a detailed examination of dynamically downscaled temperature and precipitation projections available from the North American Regional Climate Change Assessment Program (NARCCAP) for southwestern Colorado for two 30-year periods: a historic period (1971-2000) and a future period (2041-2070). The area of investigation was centered on the San Juan Mountains. Overall, the results show at least 4°F warming in all seasons, with summer having the highest warming in maximum (daytime) temperatures (>6°F) and greater increases at higher elevations (>8,000’). By the mid-21st century, the normal daytime summer temperatures are projected to be similar to those observed in 2002, the year with the highest observed summer temperatures in the San Juans. The consensus among six regional climate model (RCM) runs is that southwestern Colorado can expect near-average precipitation or a slight increase during December and January, near-average precipitation or a decrease from April to June, and a decrease in precipitation in July and August. However, none of the RCM simulations captured the monthly precipitation climatology of the region. In particular, all of the models had trouble reproducing various features of the North American Monsoon from July through September. In most cases, no monsoon was simulated, and in the remaining ones, the monsoon was not maintained for a long enough period. Additionally, a majority of the RCM simulations had problems reproducing the observed trend of increasing precipitation with elevation during the fall, winter, and spring months, the period during which the snowpack is accumulated. This analysis indicates that climate model projections of changes in precipitation have much greater uncertainty than temperature and, therefore, should be treated with greater caution.

Papers, Reports, and Presentations for this Project
Examining Regional Climate Model (RCM) projections: What do they add to our picture of future climate in the region? (Intermountain West Climate Summary July 2011)

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Drivers of Adaptation: A Comparative Analysis of Local Decision Making in the American West

Primary Investigator(s): L. Dilling, K. Andersson

Multi-year effort to systematically investigate how and why local decision makers in cities and large towns in Colorado, Utah, and Wyoming prepare for and respond to weather and climate-related risk and hazards, such as blizzards, tornadoes, and floods

As a complement to studies that examine barriers to adaptation, PIs conducted a study of the drivers that lead to planning for and responding to weather and climate-related hazards at the municipal scale as a proxy for understanding what might drive adaptive behavior towards climate change. Municipalities in Colorado, Utah, and Wyoming were chosen for the study, and researchers conducted face-to-face and phone interviews with multiple key informants in a randomly selected sample of 60 municipalities with populations over 10,000. The results suggest that municipalities do exhibit a wide variety of responses to weather and climate risk, despite similar levels of exposure in some cases. The reasons for these different responses are complex, and actions are not explainable by a single factor such as economic status or population size. Additional factors such as experiencing previous events, municipal champions, cultural values, and differences at the state level were found to have some influence, but individually these factors do not explain more than 5-15% of the variation in the municipal responses. These results have been drafted for publication, with submission expected in early summer of 2014. Following the initial interviews, the researchers conducted in-depth case studies with six of the municipalities to better understand the combinatorial relationship of the potential explanatory factors. Analysis of the case studies is currently being completed and will be submitted for publication.

Deliverables: Peer-reviewed publication forthcoming.

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Drought Adaptation Among Ranchers in the Intermountain West

Primary Investigators: William Travis, Kristen Gangwer

Identification and measurement of the effects of drought adaptations among agriculturalists in the “Three Corners” region of Colorado, Wyoming, and Utah via detailed surveys of their decision-making

Drought imposes physical, social, and economic impacts on the ranching system in the Rocky Mountains, and ranchers interviewed for this project exhibit a range of strategies for buffering against and coping with these impacts, and for adapting to dry conditions. Ranchers’ operations are comprised of varying quantities of private, privately leased, state, and federal ground – and with each of these forms of tenure come different levels of oversight on management during drought. However, for the ranchers interviewed, the complex land tenure system appears to support their drought coping and buffering strategies. It proves limiting, though, in terms of long-term adaptation to drought and/or general aridity, particularly due to range improvement policies and tenure insecurity. In addition to these system-level implications of the land tenure system, certain elements of an individual’s land holdings – including length, spatial distribution, size, composition, and perceived and real security – play an important role during drought and help explain the unequal impacts ranchers experience. This information has been compiled into a master’s thesis completed in 2011 and will be distilled into a WWA white paper.

Papers, Reports, and Presentations for this Project
K. Gangwer Master’s Thesis

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Evaluation of Drought Planning Research on the Wind River Reservation

Primary Investigator: E. McNie
Stakeholders: S. McNeeley (North Central Climate Science Center), C. Knutson (National Drought Mitigation Center), Wind River Reservation

Providing support for tribal drought planning efforts on the Wind River Reservation

In collaboration with the Eastern Shoshone and Northern Arapahoe tribes, WWA partners at the DoI NC CSC and the NDMC are developing a comprehensive drought plan for the Wind River Indian Reservation in Wyoming. The research team is developing analytical tools and provides analysis to inform the drought plan. WWA investigator McNie’s role is providing evaluation support and helping to inform the research design. She will use a typology of research approaches to guide the design and analysis of research goals, objectives and processes in order to ensure that the project meets its goals of producing useful drought information to inform future policy decisions.

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Evaluation of NIDIS Upper Colorado River Basin Drought Early Warning System

Primary Investigator: E. McNie
Stakeholder: National Integrated Drought Information System

Evaluation of utility of NIDIS’s first drought early warning system (DEWS) to provide lessons for other regional DEWS efforts

This project entailed the development a comprehensive evaluation for the National Integrated Drought Information System Upper Colorado River Basin Drought Early Warning System (UCRB DEWS). PI completed scoping interviews with UCRB DEWS personnel, semi-structured interviews with sample of UCRB DEWS stakeholders, archival research, collection of analytics of webinar and web page use, and development of a comprehensive online survey of DEWS services and products. The survey was designed to be transferrable to other DEWS locations and programs. In process of finalizing first draft of evaluation report. PI also used this project for ongoing consultation on the development of a ‘Mid-Level Climate Services Evaluation Tool’ with the International Research Institute’s Climate and Society Program at Columbia University. Beta-tested this ‘mid-level tool’ with the evaluation project conducted for the National Integrated Drought Information System Upper Colorado River Drought Early Warning System. Feedback has been provided to IRI and collaboration continues with group to revise the tool.

Deliverables: Report to NIDIS in late 2014

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Evaluation of Western Water Assessment’s “Utah Model”

Primary Investigator: E. McNie
Stakeholder: NOAA CPO RISA Program

Assessment of the preliminary results of WWA’s effort to expand its presence in Utah

This project examines what WWA calls the ‘Utah Model’ (directly hiring a boundary professional to expand WWA's geographic reach) and how this alternative approach to the traditional university-based model expanded WWA's network and provided climate-related decision-support activities in novel ways. As with many RISA activities, the Utah Model is a work in progress, so findings are rather limited at this time. Furthermore, our sample size of stakeholders is very small so this case study should be viewed as the starting point for discussions about the role of RISAs within a broader decision-support community.

Deliverables: McNie, E. (2014). The Utah Model Report. WWA Report.

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Evaporation, Drought, and the Water Cycle Across Timescales: Climate Foundational Sciences for the North Central Climate Science Center

Primary Investigator(s): I. Rangwala, J. Barsugli, B. Livneh, M. Hobbins (NIDIS)
Other Investigator(s): J. Lukas, A. Ray
Stakeholders: The Nature Conservancy, US Forest Service, other conservation agencies
Partners: J. Morisette, D. Ojima, and S. McNeeley (NCCSC); R. Rondeau, CO Natural Heritage Program; J. Rice (Southern Rockies LCC); L. Joyce (USFS Rocky Mountain Research Station); D. Llewellyn (Bureau of Reclamation); M. Friggens (US Forest Service)

Providing climate science support for the DOI North Central Climate Science Center, particularly for water cycle issues

The goals of this project are twofold: First, we aim to co-produce relevant climate information and integrate that into the socio-ecological decision making context.  This includes helping with the development of future climate scenarios for specific projects, application of existing and emerging climate products and tools, interpretation of emerging and relevant physical science research, and continuous engagement with stakeholders and boundary organizations in exploring appropriate tools and datasets. Second, we are conducting primary research into drivers of hydro-climatic trends and extremes in the North Central Great Plains and Intermountain West Regions (Missouri River Basin and Upper Colorado River Basin) across multiple timescales. These include understanding drivers of droughts and developing better indicators for short and long term drought.  We organized a 2-day workshop, September 24-25, 2015 on the application of high-resolution climate models (HRCMs) for socio-ecological adaptation in the NC CSC regions at the NOAA Earth Systems Research Laboratory in Boulder. The motivation was to explore recent advances in HRCMs and discuss how can they better inform ecological impacts modeling and adaptation projects in the US Northern Great Plains and Mountains. The workshop, attended by climate modelers and expert users of climate information for socio-ecological impacts assessment, was structured around three major themes: (a) convective precipitation, (b) land-surface feedbacks, and (c) usability of HRCM output.

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Exploring Regional Climate Service Collaborations

Primary Investigator: L. Dilling
Partners: J. Morisette (NC CSC), D. Ojima (NC CSC), L. Joyce (USDA Northern Plains Regional Hub), J. Derner (USDA Northern Plains Regional Hub)

Analyzing and reporting on collaborations among three regional climate service entities to provide lessons learned

One challenge, and opportunity, facing WWA and the RISA program is the increasing interest in delivering climate services by Federal agencies other than NOAA. While the increased investment is encouraging, it creates some challenges, and questions emerging from leadership in the Executive Branch seeking definition of these different entities. Thus far, there has been difficulty addressing this question because of the highly adaptive nature of regional climate services. WWA, and others, are faced with navigating the field of federal authorizations, regional priorities, scientific expertise, budgets, and scientific expertise on the teams leading separate Federally funded climate service efforts. However, these challenging circumstances have given rise to success stories that highlight why climate services should be conceived, developed and focused on regional priorities. WWA is collaborating with the leaders of the North Central Climate Science Center and the new Northern Plains USDA Hub to craft a paper outlining how collaboration among these entities has worked in the past, how it is working now, and how future partnerships will work. The paper will demonstrate how the allowance of an adaptive framework is an important mechanism for ensuring the most efficient synergies among these entities as they strive to collaborate with decisionmakers.

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High-Resolution Meteorological and Hydrologic Data Extension to Trans-Boundary Basins in the Conterminous U.S., Southern Canada and Northern Mexico

Primary Investigator: B. Livneh
Partner: U.S. Bureau of Reclamation

Using hydrologic modeling to examine the influence of dust deposition and climate change on snowmelt, runoff timing, and volume in the Colorado River Basin

The purpose of this project is to address questions related to Reclamation’s needs to improve existing methods of extreme precipitation estimation, as well as improved understanding of appropriate applications of model and reanalysis-based extreme precipitation data. This will involve extending the data development and model application methods featured in Livneh et al. (2013) to expand geographic coverage from contiguous U.S. to the North American Land Data Assimilation (NLDAS) domain. PI will document data and model development and demonstrate utility through evaluation of spatiotemporal statistics for temperature and precipitation, i.e. exceedance probabilities, frequency of extremes, and a comparison of drought characteristics relative to other dataset(s).

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Lessons Learned from Australia’s Drought Experiences

Primary Investigator: Brad Udall

Communicating lessons learned applicable to the Colorado River Basin from an investigation of water management in South Australia

Australian water management issues provide a unique opportunity to compare impacts and adaptations in portions of Australia, including the Murray-Darling Basin, with the Colorado River Basin. While both areas frequently face severe droughts as well as myriad sources of significant water demand, the severity of drought in portions of Australia exceeds most recent experiences in the CRB. Observing and analyzing the Australian response can provide lessons about governance structures, behavior of political institutions, and use of physical infrastructure to combat drought. WWA researcher Udall has presented on southeastern Australia’s recent experiences with drought and subsequent management and planning responses. In his talks, he describes the history of 20 years of aggressive water reform in Australia, dramatic drought, and federalization of the Murray-Darling Basin in 2007 and 2008 that led to severe political fallout. He has shared his observations on water management and drought planning with water managers, planners, and researchers in the Colorado River Basin during at least five presentations and one radio interview.

Papers, Reports, and Presentations for this Project
Stranger in a strange land: Lessons from an extended stay in Australia
Presentation to Colorado River District Annual Water Seminar, Grand Junction, CO, September 15, 2011

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NEPA, Climate Change, and Public Lands Decisionmaking

Primary Investigator: Mark Squillace

Providing legally relevant guidance on how public land management agencies can address climate change in decision documents

One of the most difficult challenges facing public land managers today is how to address climate change in a meaningful way when making decisions affecting public lands. The challenge reflects the high levels of uncertainty surrounding climate change and the potential consequences of climate change for the large and complex landscapes and ecosystems that public land agencies manage. In February 2010, the Council on Environmental Quality (CEQ) issued draft guidance to federal agencies describing how these agencies should address climate change in their decision documents. Recognizing the difficulty of the task, however, the CEQ’s draft guidance expressly disclaimed any intention of affording assistance to public land management agencies making complex land use decisions. The PIs sought to fill that gap by providing an analysis of three case studies that illustrate the complex challenges facing managers, and recommendations for CEQ and land management agencies. In their article, the researchers recommended that CEQ write regulations to hold agencies accountable for commitments to adaptive management, and that agencies make better use of programmatic analyses and tiering to better address climate change impacts.

Papers, Reports, and Presentations for this Project
Squillace, M. and Hood, A. (2012). “NEPA, Climate Change, and Public Lands Decision Making.” Environmental Law 42(2): 469-526.

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Paleohydrology of the Lower Colorado River Basin

Primary Investigators: Balaji Rajagopalan, Jeff Lukas, Lisa Wade

Building on previous efforts to understand the natural long-term variability of the Colorado River basin by generating paleohydrologic reconstructions of annual flows between Lees Ferry and Imperial Dam and the Gila River at its mouth

This project was initiated at the direction of Eric Kuhn from the Colorado River Water Conservation District, which has supported the project with District funds and also motivated the Colorado Water Institute’s support of the project. Datasets from 66 tree-ring sites were compiled, and then several different statistical methods were used to reconstruct annual naturalized flow for the Gila at its mouth and the Lower Colorado mainstem between Lees Ferry and Imperial Dam, back to at least 1612. The tree-ring reconstructions indicate that annual flow were generally lower before 1900 than during the modern gaged period. The tree-ring reconstructed flows for the Lower Basin were then used to inform a basin water-balance model similar to Rajagopalan et al. (2009), but modified to represent the flow inputs from the Gila River. System-response modeling under several different scenarios of water demand, shortage-sharing policy, and climate-change flow reductions showed that the periodic inflows from the Gila under current management substantively improve system outcomes.

Papers, Reports, and Presentations for this Project
Wade, L. (2012). Paleohydrology reconstructions for the Lower Colorado River Basin and implications for water supply reliability. MS thesis, University of Colorado.

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Pilot Climate Extension Services in Utah

Principal Investigator: Rob Gillies
Other Researchers: Rob Davies (Utah State University)

Continuing effort by WWA researchers located at the Utah Climate Center to pilot small-scale climate services relevant to various stakeholders in Utah

In 2011, PI Gillies and others at the Utah Climate Center developed multiple small-scale pilot climate services efforts. These included forecasts of first freezes intended to help famers and better atmospheric inversion predictions intended to assist in air quality protection efforts. Continuing work will look for and address new small-scale, targeted needs for climate services and continue to build a foundation for more permanent climate extension capacity in Utah.

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Reconstructing Environmental Flows on the Yampa River

Primary Investigator: Joe Barsugli

Developing a pilot effort to reconstruct natural flows in order to understand ecological responses to alterations of natural flow patterns

Regional assessment of the trade-offs between environmental flows and human demands on river flows requires a hydrological framework which enables the consistent examination of the ecological response to more or less alteration of daily and other natural flow patterns. This framework is a comprehensive regional water management tool for integrating the flow needs of river ecosystems with human water needs. The PI developed an improved calibration strategy (the sequence of steps that one goes through in order to calibrate the model) and improved meteorological forcing data for the Variable Infiltration Capacity (VIC) hydrologic model to provide a more robust and extensive set of natural flows for assessing the ecological response to water management actions across the Colorado River Basin. The underlying data was then assessed the Yampa-White Basin to determine how the calibration can be extended to the rest of the Colorado River Basin. Streamflow data will soon be made available on a server. Future work will aim to (a) further develop the meteorological forcing data to better represent smaller scale variations in precipitation, (b) gather and assess the quality of naturalized streamflows, including the CBRFC daily quasi-natural flows, and (c) extend the calibration of VIC to the Upper Colorado basin.

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Regional Extremes Database and Event Maps

Primary Investigators: W. Travis, J. Lukas, K. Wolter
Other Investigators: A. McCurdy
Stakeholders: Hazard mitigation planners, emergency managers, water resource managers

Developing a database and visualizations of extreme events to assist hazard planners and emergency managers.

Extreme events cause the majority of societal costs related to weather and climate and can provoke adaptive responses. WWA has begun a new focus that is designed to place extreme events in the context of historical climate variability and projected climate change, assess how risk varies over time and space, and examine how extreme events interact with place-based vulnerability. The first activity in this new research theme has been to build a database of historical extreme weather and climate events in the WWA three-state region (Colorado, Utah and Wyoming). This regional extremes database is intended to be useful to hazard planners and emergency managers trying to identify where and when the risk for different types of extreme events is greatest. It will also serve as a foundation for further research on what leads to the variation in risk over time and space. Two databases have been compiled: a selective roster of ~160 of the highest-impact weather and climate events in the three-state region back to the mid-1800s, and a more comprehensive dataset from culled from the NOAA NCEI Storm Events Database focused on the post-1950 period that includes over 20,000 weather events. The roster of high-impact events has been reviewed by all three of the state climate offices in our region, and as of spring 2016 is available on the WWA website.  From the larger dataset of storm events, we generated a set of monthly occurrence maps, by county, for ten different event types, and these are also available on the WWA website.  We are currently reaching out to stakeholders to solicit suggestions to refine these products and apply the data. 

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Regional Integration Among Municipal and Industrial (M&I) Water Providers

Primary Investigators : Doug Kenney, Kelsey Cody

Case-based analysis of regional integration among M&I water providers in the West as a means of improving resiliency in the face of climate change

Across the West, coalitions of municipal and industrial (M&I) water providers have increasingly looked to regional integration of both their physical and institutional systems as a means of dealing with common pressures associated with population growth and climate variability and change. In order to better understand the forces that can stimulate these efforts, the possible forms of the resulting integration, and the overall efficacy of this management strategy, this project reviewed three cases where regional integration is a prominent feature of policy: southern Nevada, California, and the Front Range of Colorado. The cases demonstrate that infrastructural integration and institutional connectedness go hand in hand, and can emerge together, or evolve from either point.  Once established, these relationships can be useful in illuminating drawbacks to competition and benefits of cooperative action.  In the case study regions, the resiliency of water systems appears to have improved (or the rate of decline has slowed), as evidenced by decreases in per capita demand, increased infrastructure connectivity and efficiency, and increased available resources. Regional integration, however, is not without drawbacks. Breaking the bond between water scarcity and competitive behavior at the regional scale is difficult to do without merely shifting the point of competition to other scales.

Papers, Reports, and Presentations for this Project
WWA White Paper: Regional Integration of M&I Water Providers as a Climate Change Adaptation Strategy

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The Role of States in Enabling Adaptive Capacity for Water Governance

Primary Investigators: L. Dilling, C. Kirchhoff (U. of Conn.)
Stakeholders: State governments, water management agencies

Worldwide water governance failures undermine effective water management under uncertainty and change. Overcoming these failures requires employing more adaptive, resilient water management approaches; yet, while scholars have advance theory of what adaptive, resilient approaches should be, there is little empirical evidence to support those normative propositions. To fill this gap, we reviewed the literature to derive theorized characteristics of adaptive, resilient water governance including knowledge generation and use, participation, clear rules for water use, and incorporating nonstationarity. Then, using interviews and documentary analysis focused on five U.S. states’ allocation and planning approaches, we examined empirically if embodying these characteristics made states more (or less) adaptive and resilient in practice. We found that adaptive, resilient water governance requires not just possessing these characteristics but combining and building on them. That is, adaptive, resilient water governance requires well-funded, transparent knowledge systems combined with broad, multilevel participatory processes that support learning, strong institutional arrangements that establish authorities and rules and that allow flexibility as conditions change, and resources for integrated planning and allocation. We also found that difficulty incorporating climate change or altering existing water governance paradigms and inadequate funding of water programs undermine adaptive, resilient governance.

Kirchhoff, C. J., & Dilling, L. (2016). The role of US states in facilitating effective water governance under stress and change. Water Resources Research, n/a–n/a.

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Snowmelt Perturbations and Water Supply Forecast Errors

Primary Investigators: J. Deems, B. Livneh, C. Wessman, N. Molotch, J. Barsugli, K. Wolter
Stakeholders: NOAA NWS Colorado Basin River Forecast Center, water managers using CBRFC streamflow forecasts
Partners: NIDIS, NOAA NWS Colorado Basin River Forecast Center, Institute for Arctic and Alpine Research (Univ. of Colorado)

A collaborative effort among WWA hydrologists, ecologists, weather and climate experts, and operational forecasters at the NOAA Colorado Basin River Forecast Center in an effort to use a suite of modeling and observation techniques to better understand drivers of snow accumulation and melt in the Upper Colorado River Basin with the ultimate goal of improving CBRFC forecasts

Since 2002, the headwaters of the Colorado River and nearby basins have experienced extensive changes in land cover, raising questions about streamflow and forecast accuracy. Widespread tree mortality from bark beetle infestation has taken place across a range of forest types, elevation, and latitude. Extent and severity of forest structure alteration have been observed through a combination of aerial survey satellite remote-sensing, and in situ measurements. Additional perturbations have resulted from deposition of dust from regional dry-land sources on mountain snowpacks that strongly alter the snow surface albedo, driving earlier and faster snowmelt runoff. These perturbations likely result in abnormalities between the historical relationships between the quantity of snowfall and the resulting streamflow volume, which provide the basis for operational water supply forecasts. This project sought identify the effect of these perturbations on streamflow generation, providing water resource managers guidance as to how operational water supply forecast models may need to be augmented to account for changes in runoff production. PIs drove the Distributed Hydrology and Vegetation Model (DHSVM) with observed meteorology, distributed satellite-based snowpack information, time-varying maps of leaf area index and forest properties to emulate bark beetle impacts, and parameterizations of snow albedo based on observations of dust forcing. Results from beetle-killed canopy alteration suggest slightly greater snow accumulation as a result of less interception and reduced canopy sublimation, contributing to overall increases in annual water yield on the order of 10%. However, understory regeneration roughly halves the changes in water yield. Contrasted against a purely observational estimate of runoff efficiency change with cumulative forest mortality, the results suggest comparable sensitivities; however, positive water yield changes are not statistically significant. The primary hydrologic impact of dust-on-snow forcing is an increased rate of snowmelt associated with more extreme dust deposition, producing earlier peak streamflow rates for snowmelt-dominated catchments on the order of 1–3 weeks. Future work based on this project may focus on methods to ingest spatial hydrologic information into the NOAA CBRFC streamflow forecasting processes to improve forecast model representation of these perturbations.

Livneh B., J.S. Deems., D. Schneider, J. Barsugli, and N.P. Molotch (2014), Filling in the Gaps: Inferring Spatially Distributed Precipitation from Gauge Observations over Complex Terrain. Water Resources Research, in review

Livneh B., J.S. Deems, B. Buma, J.J. Barsugli, D. Schneider, N.P. Molotch, K. Wolter, and C.A. Wessman, 2014: Catchment Response to Bark Beetle Outbreak in the Upper Colorado River Basin, Journal of Geophysical Research (in review).

Multiple efforts to integrate research findings into CBRFC operations.

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A Socioeconomic Impacts and Adaptation Strategies Clearinghouse

Primary Investigators: Roberta Klein, William Travis

Development of an online, searchable database to provide stakeholders with resources regarding socioeconomic impacts of climate change in the Western Water Assessment region

This project entailed the creation of an online, searchable database of research on socioeconomic impacts of climate change in the Intermountain West. It has been populated with more than 160 items, including peer- and non-peer-reviewed articles, reports, websites, presentations, etc. addressing the socioeconomic impacts of various climate phenomena.  The items can be sorted by sector (e.g., agriculture, outdoor recreation, water), phenomenon (climate variability, climate change, drought, floods, fire, heat waves, extreme events), and the geographical location(s) the item focuses on. In general, there was more literature about the socioeconomic impacts of climate variability and change on outdoor recreation than initially expected. The PIs have drafted two separate white papers to capture the state of existing knowledge on socioeconomic impacts of drought in the West.

Papers, Reports, and Presentations for this Project
Socioeconomic Impacts Database

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Stochastic Streamflow Simulation at Interannual and Interdecadal Time Scales and Implications to Water Resources Management in the Colorado River Basin

Primary Investigators: Balaji Rajagopalan, Edith Zagona, Ken Nowak, Cameron Bracken

Analysis of streamflow variability at short (interannual) and long (interdecadal) time scales to support Bureau of Reclamation management activities on the Colorado River

This multi-year effort was aimed at benefiting the Bureau of Reclamation from the integration of stochastic simulation techniques into planning and the development of the new Midterm Operations Model for the Colorado River Basin. To understand how streamflow has varied at interannual and interdecadal time scales, WWA researchers Rajagopalan, Nowak, Zagona, and Bracken empoyed suite of methodologies. At the interdecadal time scale, wavelet analysis was used to demonstrate the climatic drivers of streamflow variability, and a stochastic simulation of multisite streamflow with nonstationary spectral features was developed. At the interannual time scale, hidden Markov models were used to demonstrate that short-term changes in streamflow are greater than indicated by standard time-series analysis. In addition, development of a new probabilistic Midterm Operations Model was completed and is now in use by the Bureau of Reclamation.

Papers, Reports, and Presentations for this Project

Bracken, C. (2011). Seasonal to Inter-Annual Streamflow Simulation and Forecasting on the Upper Colorado River Basin and Implications for Water Resources Management. M.S. Thesis, Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder.

Bracken, C., B. Rajagopalan, and J. Prairie. (2010). A Multi-Site Seasonal Ensemble Streamflow Forecasting Technique. Water Resources Research 46: W03302.

Nowak, K., M. Hoerling, B. Rajagopalan, E. and Zagona. (2012). Colorado River Basin Hydroclimatic Variability. Journal of Climate 25(12): 4389.

Nowak, K. (2011). Stochastic Streamflow Simulation at Interdecadal Times Scales and Implications for Water Resources Management in the Colorado River Basin. Ph.D. Thesis, Department of Civil, Environmental, and Architectural Engineering, University of Colorado Boulder.

Nowak, K., B. Rajagopalan, and E. Zagona. (2011). Wavelet Auto-Regressive Method (WARM) for multi-site streamflow simulation of data with non-stationary spectra. Journal of Hydrology, 410 (1-2): 1-12.

Nowak, K., J. Prairie, B. Rajagopalan, and U. Lall, (2010). A nonparametric stochastic approach for multisite disaggregation of annual to daily streamflow. Water Resources Research 46: W08529

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Towards Frameworks for Climate Services: Meeting the Needs of Different Users with Different Information Requirements

Primary Investigators: Kristen Averyt, Tim Bardsley, Kevin Werner (CBRFC), Gigi Owen (CLIMAS)

Demonstrating the River Forecast Center (RFC) Water Resources Outlook tool at user workshops to help identify differences in the user populations and determine changes in the Water Resources Outlook product that might be necessary for different types of users

WWA researchers Kristen Averyt and Tim Bardsley worked with the NOAA Colorado Basin River Forecast Center (CBRFC) to better understand how water managers interpret and use streamflow forecast information through a series of interactive workshops. Workshops were held in January 2011 at the AMS Meeting in Seattle, WA in conjunction with a short course on water resources and in June 2011 in Salt Lake City. During these workshops the researchers introduced a gaming exercise that involved forecasted flows and reservoir schedules. These engagements have improved managers’ understanding of available products and user driven improvements to CBRFC web based tools. In addition, scenario-based exercises indicate that most participants tend to use the median forecasts rather than worst-case scenario predicted at the tails of forecast ranges, and many use a wait-and-see approach to planning.  These efforts are feeding into continued adjustment of decision support forecasts based on improved understanding of decision-making constraints and processes.

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Update of the Climate Change in Colorado report

Primary Investigator(s): J. Lukas
Stakeholders: Colorado Water Conservation Board; water managers and planners across the state of Colorado
Partners: Colorado Water Conservation Board

Comprehensive synthesis of observed and projected climate co-produced directly with the Colorado Water Conservation Board

WWA is comprehensively updating and expanding their well-received 2008 Climate Change in Colorado report, also co-produced by WWA and the CWCB. The report synthesizes the best available climate science relevant to the state’s water resources. Like the original, the updated report covers the observed climate patterns and trends in Colorado, a primer on climate models, linking observed state trends with global changes, projections of future climate and hydrology, and guidance on using this information in planning and management. Several dozen stakeholders at the local, state, and federal levels reviewed or contributed to the updated report. One key area of updating was using the new CMIP5 global climate model output; for Colorado, CMIP5 shows a modest shift towards wetter projected precipitation outcomes compared to the previous CMIP3 models. This presented a challenge: acknowledging the resulting shift in ensemble-average modeled runoff, while reaffirming the need to prepare for a broad range of hydrologic outcomes.

Deliverables: Climate Change in Colorado report released in August 2014
Leveraged Funding: Colorado Water Conservation Board

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Water-Energy-Climate Change Nexus

Primary Investigator: Doug Kenney, Kristen Averyt

Publication of a book providing an overview of the nexus among water, energy, and climate issues in the western United States

In 2011, Edward Elgar Publishing produced The Water-Energy Nexus in the Western United States, edited by Kenney (WWA) and Robert Wilkinson. It features contributions from authors drawn from a network of researchers and decisionmakers working on energy-water issues, including WWA’s Averyt. The research and analyses presented in the book demonstrate that the choices that must be made in order to continue the sustainable development and management of water and energy systems to meet public needs in under future scenarios of climate and other changes. 

Papers, Reports, and Presentations for this Project
Kenney, D. S., and R. Wilkinson (editors). 2011. The Water-Energy Nexus in the Western United States. Cheltenham: Edward Elgar Publishing.

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Water, Energy, and Climate Change: Freshwater Use by Power Plants in the United States

Primary Investigators: K. Averyt, J. Meldrum, I. Rangwala
Stakeholders: Public utility commissions, USGS, DOE, water resource planners, electric utilities
Partners: S. Tellinghuisen (Western Resource Advocates), R. Newmark (NREL), J. Macknick (NREL), D. Yates (NCAR)

Understanding the impacts of electricity generation on freshwater resources in a warming world

PIs have been actively publishing research exploring critical questions at the nexus between energy and water. Particular attention has been paid to the impacts of shifts in water resources on national and regional electricity generation. The research completed in 2012-13, and published through 2013 explores this issue on the national scale, in the A-C-T Basin in the Southeast, and in the Colorado River Basin. Further work showed that although power plants, on average, are not contributing to water stress, building a single thermoelectric plant can directly impact local water availability for other uses in a way that establishing a single farm cannot. Therefore, it is important to consider sensitivity of water resources when siting power plants. Currently, WWA is engaged in a project through the Joint Institute for Strategic Energy Analysis (JISEA), where PIs are mapping future electricity demands, future water demands, onto water availability as defined by 3 different climate scenarios derived from CMIP5 output. A paper on that work is forthcoming.

Deliverables (from overarching project): Averyt, K, J Macknick, J Rogers, N Madden, J Fisher, J Meldrum and R Newmark (2013), Water use for electricity in the United States: an analysis of reported and calculated water use information for 2008. Environ. Res. Lett., 8 (1); Averyt, K, J Meldrum, P Caldwell, G Sun, S McNulty, A Huber-Lee and N Madden (2013), Sectoral contributions to surface water stress in the coterminous United States. Environ. Res. Lett., 8 (3); Yates, D, J Meldrum and K Averyt (2013), The influence of future electricity mix alternatives on southwestern US water resources. Environ. Res. Lett., 8 (4); S. Cohen, J. Meldrum, K. Averyt, J. Macknick, I. Rangwala (in preparation) Sensitivity of powerplant development to different CMIP5 hydrologic projections.

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Weber Basin Climate Sensitivity Analysis

Primary Investigator(s): T. Bardsley
Stakeholders: Weber Basin Water Conservancy District, Utah Division of Water Resources
Partners: D. Rosenberg (Utah State University), M. Bekker (Brigham Young University), A. Wood (NCAR), M. Hobbins (NOAA ESRL PSD), D. Cole (Utah Div. of Water Resources), T. Adams (Utah Div. of Water Resources), C. Hasenyager (Utah Div. of Water Resources), S. McGettiagan (Utah Div. of Water Resources), J. Lhotak (NOAA NWS CBRFC), C. Peterson (NOAA NWS CBRFC)

Exploring climate change impacts on water supplies from the Weber River Basin

This project came from a request by Weber Basin Water Conservancy district to explore climate change impacts to the Weber River water supply in collaboration with the Utah Division of Water Resources (UTDWR). UTDWR has developed a water supply model for the Weber River, which has been re-coded from the original Fortran to integrate into the Water Evaluation And Planning (WEAP) model by Utah State University (USU). The goal of the project is to develop relevant and defensible climate change scenarios and climate perturbed hydrologies, using the CBRFC model and evaluate impacts to the current operations of the Weber River system. Recently published tree-ring reconstructed streamflows may also be evaluated to explore extreme drought conditions beyond those in the observed record. The model will facilitate the exploration of a variety of new management, infrastructure, or demand changes to retain a resilient system. Initial work has focused on evaluating climate change sensitivities across multiple flow points on the Weber river and addressing evapotranspiration and model calibration.

Deliverables: Presentation and report to Weber Basin Water Conservancy District forthcoming

Leveraged Funding: In-kind staff efforts from NOAA Colorado Basin River Forecast Center, Utah State University, Brigham Young University, National Center for Atmospheric Research, and NOAA Earth Systems Research Laboratory Physical Sciences Division

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