Toward usable predictive climate information at decadal timescales

Abstract

•An interdisciplinary research framework works toward usable climate predictions•Discussions around prediction images engaged stakeholders and built understanding•Potentially usable image formats are identified for key water management needs•The framework may be transferable to other climate and decision contexts In this era of a changing climate, usable climate information is more important than ever. A new branch of climate science is generating multi-year climate predictions that bridge the gap between seasonal forecasts and climate projections. Yet the societal benefits of climate information on the multi-year timescale are largely unexplored. This research brought together physical and social scientists, statisticians, engineers, and water managers to understand how to develop useable multi-year climate predictions for the case of water managers in the western United States. We worked together to understand overlaps between what information is credible and what information is needed. We created presentation formats that are potentially usable for adaptation planning and testing, public messaging, justification of long-term investments, and engaging policy makers. Wider application of our research methods has the potential to more broadly strengthen our ability to withstand near-term climate extremes. Decadal climate predictions provide information out to the 10-year timescale, bridging the gap between seasonal and climate projections. This paper presents an interdisciplinary research framework to develop credible and use-relevant decadal climate predictions. We focused on case studies of flood risk and water resource management in Colorado and California. Climate- and stakeholder-oriented research streams iterate and build on each other, coming together over time to inform the development of decadal prediction images. These images are discussed with stakeholders to identify potentially usable formats and the decisions they may inform. Several potentially usable formats are identified: predictions alongside projections, predictions relative to historical climate, multivariate information, and information at the weather scale and in terms of hydrologic impacts. These image formats are potentially usable for climate adaptation planning and testing, public messaging, and justification of long-term investments and to engage policy makers around objectives. We conduct a critical review of the framework as implemented here and discuss its general applicability to other climate regions and decision contexts. Decadal climate predictions provide information out to the 10-year timescale, bridging the gap between seasonal and climate projections. This paper presents an interdisciplinary research framework to develop credible and use-relevant decadal climate predictions. We focused on case studies of flood risk and water resource management in Colorado and California. Climate- and stakeholder-oriented research streams iterate and build on each other, coming together over time to inform the development of decadal prediction images. These images are discussed with stakeholders to identify potentially usable formats and the decisions they may inform. Several potentially usable formats are identified: predictions alongside projections, predictions relative to historical climate, multivariate information, and information at the weather scale and in terms of hydrologic impacts. These image formats are potentially usable for climate adaptation planning and testing, public messaging, and justification of long-term investments and to engage policy makers around objectives. We conduct a critical review of the framework as implemented here and discuss its general applicability to other climate regions and decision contexts. Climate risk managers are increasingly interested in predictive climate information that is analyzed and presented in decision-relevant terms to enable appropriate planning and adaptation to future conditions. The use of uninitialized general circulation model (GCM) projections of future climate statistics is now commonplace in long-range planning fields affected by climate, including water management.1Cook L.M. McGinnis S. Samaras C. The effect of modeling choices on updating intensity-duration-frequency curves and stormwater infrastructure designs for climate change.Clim. Change. 2020; 159: 289-308https://doi.org/10.1007/s10584-019-02649-6Crossref Scopus (27) Google Scholar On shorter timescales, initialized seasonal climate forecasts are also increasingly used in decision-making.2Bruno Soares M. Daly M. Dessai S. Assessing the value of seasonal climate forecasts for decision-making.Wiley Interdiscip. Rev. Clim. Change. 2018; 9https://doi.org/10.1002/wcc.523Crossref Scopus (47) Google Scholar, 3Goddard L. Kumar A. Solomon A. Smith D. Boer G. Gonzalez P. Kharin V. Merryfield W. Deser C. Mason S.J. Kirtman B.P. A verification framework for interannual-to-decadal predictions experiments.Clim. Dyn. 2013; 40: 245-272https://doi.org/10.1007/s00382-012-1481-2Crossref Scopus (237) Google Scholar, 4Goddard L. Hurrell J.W. Kirtman B.P. Murphy J. Stockdale T. Vera C. Two time scales for the price of one (almost).Bull. Amer. Meteorol. Soc. 2012; 93: 621-629https://doi.org/10.1175/BAMS-D-11-00220.1Crossref Scopus (47) Google Scholar Whether climate projections or seasonal forecasts, future climate information generated by GCMs contains error and bias, but has the potential to be useful if the information is co-developed with risk managers.5Cobb A. Done J.M. The use of global climate models for tropical cyclone risk assessment.in: Collins J.M. Walsh K. Hurricanes and Climate Change. Springer, 2017: 167-186Crossref Scopus (3) Google Scholar,6Watson C.C. Johnson M.E. Integrating hurricane loss models with climate models.in: Diaz H.F. Murnane R.J. Climate Extremes and Society. Cambridge University Press, 2008: 209-224Crossref Scopus (74) Google Scholar Specifically, water managers have become sophisticated users and key partners in the advancement of predictive climate science.4Goddard L. Hurrell J.W. Kirtman B.P. Murphy J. Stockdale T. Vera C. Two time scales for the price of one (almost).Bull. Amer. Meteorol. Soc. 2012; 93: 621-629https://doi.org/10.1175/BAMS-D-11-00220.1Crossref Scopus (47) Google Scholar Decadal climate predictions provide climate information out to the 10-year timescale, bridging the gap between climate projections and seasonal forecasts. Climate change projections typically provide long-term linear climate trends, whereas predictions provide time-varying trajectories that account for climate variability and change. In this sense, projections may be considered as what-if scenarios that do not favor specific phases of variability, whereas predictions have the potential to provide credible near-term climate trajectories. Potential decadal prediction skill arises from initializing with current conditions, such as starting within a particular climate mode, as well as from representing the climate response to existing and future greenhouse gases.7Meehl G.A. Goddard L. Murphy J. Stouffer R.J. Boer G. Danabasoglu G. Dixon K. Giorgetta M.A. Greene A.M. Hawkins E. et al.Decadal prediction: can it be skillful?.Bull. Amer. Meteorol. Soc. 2009; 90: 1467-1485https://doi.org/10.1175/2009BAMS2778.1Crossref Scopus (562) Google Scholar,8Lee T.C. Zwiers F.W. Zhang X. Tsao M. Evidence of decadal climate prediction skill resulting from changes in anthropogenic forcing.J. Clim. 2006; 19: 5305-5318https://doi.org/10.1175/JCLI3912.1Crossref Scopus (38) Google Scholar Currently, skill in decadal predictions varies by region and climate-related variable, and is generally higher for ocean variables than for atmospheric or land variables.9Yeager S.G. Danabasoglu G. Rosenbloom N.A. Strand W. Bates S.C. Meehl G.A. Karspeck A.R. Lindsay K. Long M.C. Teng H. Lovenduski N.S. Predicting near-term changes in the Earth System: a large ensemble of initialized decadal prediction simulations using the Community Earth System Model.Bull. Am. Meteorol. Soc. 2018; 99: 1867-1886https://doi.org/10.1175/BAMS-D-17-0098.1Crossref Scopus (111) Google Scholar Further, due to advances in understanding, recent studies have demonstrated that the skill of multi-year predictions of the climate system is improving.7Meehl G.A. Goddard L. Murphy J. Stouffer R.J. Boer G. Danabasoglu G. Dixon K. Giorgetta M.A. Greene A.M. Hawkins E. et al.Decadal prediction: can it be skillful?.Bull. Amer. Meteorol. Soc. 2009; 90: 1467-1485https://doi.org/10.1175/2009BAMS2778.1Crossref Scopus (562) Google Scholar,9Yeager S.G. Danabasoglu G. Rosenbloom N.A. Strand W. Bates S.C. Meehl G.A. Karspeck A.R. Lindsay K. Long M.C. Teng H. Lovenduski N.S. Predicting near-term changes in the Earth System: a large ensemble of initialized decadal prediction simulations using the Community Earth System Model.Bull. Am. Meteorol. Soc. 2018; 99: 1867-1886https://doi.org/10.1175/BAMS-D-17-0098.1Crossref Scopus (111) Google Scholar, 10Smith D.M. Eade R. Scaife A.A. Caron L.P. Danabasoglu G. DelSole T.M. Delworth T. Doblas-Reyes F.J. Dunstone N.J. Hermanson L. Kharin V. Robust skill of decadal climate predictions.NPJ Clim. Atmos. Sci. 2019; 2: 1-10https://doi.org/10.1038/s41612-019-0071-yCrossref Scopus (93) Google Scholar, 11Smith D.M. Scaife A.A. Boer G.J. Caian M. Doblas-Reyes F.J. Guemas V. Hawkins E. Hazeleger W. Hermanson L. Ho C.K. Ishii M. Real-time multi-model decadal climate predictions.Clim. Dyn. 2013; 41: 2875-2888https://doi.org/10.1007/s00382-012-1600-0Crossref Scopus (92) Google Scholar, 12Hawkins E. Robson J. Sutton R. Smith D. Keenlyside N. Evaluating the potential for statistical decadal predictions of sea surface temperatures with a perfect model approach.Clim. Dyn. 2011; 37: 2495-2509https://doi.org/10.1007/s00382-011-1023-3Crossref Scopus (49) Google Scholar There is also some evidence of multi-year predictive skill in some metrics of climate extremes.13Eade R. Hamilton E. Smith D.M. Graham R.J. Scaife A.A. Forecasting the number of extreme daily events out to a decade ahead.J. Geophys. Res. 2012; 117https://doi.org/10.1029/2012JD018015Crossref Scopus (38) Google Scholar,14Hanlon H.M. Hegerl G.C. Tett S.F.B. Smith D.M. Can a decadal forecasting system predict temperature extreme indices?.J. Clim. 2013; 26: 3728-3744https://doi.org/10.1175/JCLI-D-12-00512.1Crossref Scopus (25) Google Scholar However, evidence for skill in multi-year hydrologic predictions is mixed and can be limited by poor precipitation prediction skill.15Chikamoto Y. Wang S.Y.S. Yost M. Yocom L. Gillies R.R. Colorado River water supply is predictable on multi-year timescales owing to long-term ocean memory.Commun. Earth Environ. 2020; 1: 1-11https://doi.org/10.1038/s43247-020-00027-0Crossref Scopus (6) Google Scholar,16Neri A. Villarini G. Salvi K. Slater L.J. Napolitano F. On the decadal predictability of the frequency of flood events across the U.S. Midwest.Int. J. Climatol. 2019; 39: 1796-1804https://doi.org/10.1002/joc.5915Crossref Scopus (8) Google Scholar But overall, decadal prediction science is at an early stage, relative to the science of climate projections and seasonal forecasts. While decadal prediction science continues to advance,17Merryfield W.J. Baehr J. Batté L. Becker E.J. Butler A.H. Coelho C.A.S. Danabasoglu G. Dirmeyer P.A. Doblas-Reyes F.J. Domeisen D.I.V. et al.Current and emerging developments in subseasonal to decadal prediction.Bull. Amer. Meteorol. Soc. 2020; 101: E869-E896https://doi.org/10.1175/BAMS-D-19-0037.1Crossref Scopus (61) Google Scholar,18Cassou C. Kushnir Y. Hawkins E. Pirani A. Kucharski F. Kang I.-S. Caltabiano N. Decadal climate variability and predictability: challenges and opportunities.Bull. Amer. Meteorol. Soc. 2018; 99: 479-490https://doi.org/10.1175/BAMS-D-16-0286.1Crossref Scopus (52) Google Scholar parallel efforts to understand and improve its societal value have received less attention, despite the multi-year timescale aligning well with near-term climate planning needs19Sandgathe S. Brown B.R. Carman J.C. Infanti J.M. Johnson B. McCarren D. McIlvain E. Exploring the need for reliable decadal prediction.Bull. Amer. Meteorol. Soc. 2020; 101: E141-E145https://doi.org/10.1175/BAMS-D-19-0248.1Crossref Scopus (4) Google Scholar, 20Vera C. Barange M. Dube O.P. Goddard L. Griggs D. Kobysheva N. Odada E. Parey S. Polovina J. Poveda G. Seguin B. Needs assessment for climate information on decadal timescales and longer.Proc. Environ. Sci. 2010; 1: 275-286Crossref Scopus (41) Google Scholar, 21Barsugli J. Anderson C. Smith J.B. Vogel J.M. Options for Improving Climate Modeling to Assist Water Utility Planning for Climate Change. Western Utilities Climate Alliance (WUCA), 2009: 144https://www.wucaonline.org/assets/pdf/pubs-whitepaper-120909.pdfGoogle Scholar and the emerging availability of real-time multi-year predictions.11Smith D.M. Scaife A.A. Boer G.J. Caian M. Doblas-Reyes F.J. Guemas V. Hawkins E. Hazeleger W. Hermanson L. Ho C.K. Ishii M. Real-time multi-model decadal climate predictions.Clim. Dyn. 2013; 41: 2875-2888https://doi.org/10.1007/s00382-012-1600-0Crossref Scopus (92) Google Scholar,22Kushnir Y. Scaife A.A. Arritt R. Balsamo G. Boer G. Doblas-Reyes F. Hawkins E. Kimoto M. Kolli R.K. Kumar A. et al.Towards operational predictions of the near-term climate.Nat. Clim. Change. 2019; 9: 94-101https://doi.org/10.1038/s41558-018-0359-7Crossref Scopus (66) Google Scholar This presents an opportunity to better align the advancing physical science with societal need.23Morss R.E. Wilhelmi O.V. Downton M.W. Gruntfest E. Flood risk, uncertainty, and scientific information for decision making: lessons from an interdisciplinary project.Bull. Am. Meteorol. Soc. 2005; 86: 1593-1601https://doi.org/10.1175/BAMS-86-11-1593Crossref Scopus (190) Google Scholar,24McNie E.C. Reconciling the supply of scientific information with user demands: an analysis of the problem and review of the literature.Environ. Sci. Pol. 2007; 10: 17-38https://doi.org/10.1016/j.envsci.2006.10.004Crossref Scopus (650) Google Scholar Indeed, Meehl et al.7Meehl G.A. Goddard L. Murphy J. Stouffer R.J. Boer G. Danabasoglu G. Dixon K. Giorgetta M.A. Greene A.M. Hawkins E. et al.Decadal prediction: can it be skillful?.Bull. Amer. Meteorol. Soc. 2009; 90: 1467-1485https://doi.org/10.1175/2009BAMS2778.1Crossref Scopus (562) Google Scholar suggest that the value of the decadal predictions should be quantified in terms of social and economic value (see also Murphy).25Murphy A.M. What is a good forecast? An essay on the nature of goodness in weather forecasting.Wea. Forecast. 1993; 8: 281-293https://doi.org/10.1175/1520-0434(1993)008<0281:WIAGFA>2.0.CO;2Crossref Scopus (509) Google Scholar Bruno-Soares et al.26Bruno Soares M. Alexander M. Dessai S. Sectoral use of climate information in Europe: a synoptic overview.Clim. Serv. 2018; 9: 5-20https://doi.org/10.1016/j.cliser.2017.06.001Crossref Scopus (74) Google Scholar concur that more effort should be focused on translating predictions into usable information. Yet, presenting weather and climate information in ways that are useful to stakeholders remains challenging.27Morss R.E. Demuth J.L. Lazo J.K. Communicating uncertainty in weather forecasts: a survey of the U.S. public.Wea. Forecast. 2008; 23: 974-991https://doi.org/10.1175/2008WAF2007088.1Crossref Scopus (201) Google Scholar As such, these advances and opportunities represent a research gap that needs to be addressed. This paper aims to fill that gap by (1) presenting an interdisciplinary research framework that combines stakeholder-oriented and climate research-oriented research streams, to develop credible and usable decadal scale information, and (2) illustrating the implementation of that framework to investigate the utility of decadal timescale information for water management. The framework presented here was implemented as part of a multi-year, multi-disciplinary project called UDECIDE (Understanding Decision-Climate Interactions on Decadal Scales) with the goal to create usable predictive climate information at the decadal timescale. Rather than discuss details and results of each of the contributing research components, this paper focuses on the framework and how it can be used to enhance the societal value of science through interdisciplinary, multi-method research. Specifically, we share our experience of integrating climate and stakeholder research to realize usable predictive climate information. The culmination of this integration is the production of prediction images that are tested with stakeholders to identify decadal prediction outputs that are potentially usable, and to explore which specific decisions such outputs may inform. The UDECIDE framework builds upon the body of knowledge on usable climate information, specifically on the need for continued iteration between knowledge producers and users28Dilling L. Lemos M.C. Creating usable science: opportunities and constraints for climate knowledge use and their implications for science policy.Glob. Environ. Change. 2011; 21: 680-689https://doi.org/10.1016/j.gloenvcha.2010.11.006Crossref Scopus (665) Google Scholar and relevance to the decision contexts.29Mehta V.M. Knutson C.L. Rosenberg N.J. Olsen J.R. Wall N.A. Bernadt T.K. Hayes M.J. Decadal climate information needs of stakeholders for decision support in water and agriculture production sectors: a case study in the Missouri River Basin.Weather, Clim. Soc. 2013; 5: 27-42https://doi.org/10.1175/WCAS-D-11-00063.1Crossref Scopus (31) Google Scholar,30Moss R.H. Meehl G.A. Lemos M.C. Smith J.B. Arnold J.R. Arnott J.C. Behar D. Brasseur G.P. Broomell S.B. Busalacchi A.J. et al.Hell and high water: practice-relevant adaptation science.Science. 2013; 342: 696-698https://doi.org/10.1126/science.1239569Crossref PubMed Scopus (140) Google Scholar The framework was implemented here for the cases of flood risk and water resource management in Colorado and California, allowing for the comparison of results across different climates and decision contexts. Methods were chosen to support our specific case studies, but the research framework is general, and may be modified for use in other climate and decision contexts. Some project components have been published in detail elsewhere, and are referenced herein. Other components are summarized here with details to be presented in future publications. This paper builds on an earlier project summary by providing a comprehensive demonstration and discussion of the integrated research framework.31Morss R.E. Done J.M. Lazrus H. Towler E. Tye M.R. Assessing and communicating uncertainty in decadal climate predictions: connecting predictive capacity to stakeholder needs.CLIVAR Variations. 2018; https://doi.org/10.5065/D62N513RCrossref Google Scholar Our interdisciplinary project necessarily requires diverse disciplinary expertise. The project team combined deep expertise in statistics, social and physical climate science, hydrology, and water resource engineering. Perhaps most importantly, the project team includes experience in conducting successful interdisciplinary science projects.32Morss R.E. Lazrus H. Demuth J.L. The “inter” within interdisciplinary research: strategies for building integration across fields.Risk Anal. 2021; 41: 1152-1161https://doi.org/10.1111/risa.13246Crossref PubMed Scopus (13) Google Scholar The results section starts with a description of how we worked to integrate the research streams as the project evolved. This is followed by a summary of promising entry points for creating usable decadal climate information. A summary discussion is provided, and further details of the specific research methods are described under experimental procedures. This section describes project results, starting with an overview of how we worked within the interdisciplinary research framework and then detailing results of the disciplinary and integrated research activities. Our purpose is not to describe the detailed research results of each activity (these are being published elsewhere), but to document how the activities built on one another toward the end goal of creating usable decadal climate information. Through this process, we identified and developed promising entry points for creating usable decadal climate information. UDECIDE designed an interdisciplinary research framework to explore its utility toward realizing the opportunities presented by the decadal timescale for creating usable climate information (Figure 1). The framework consists of a stakeholder-oriented research stream and a climate research stream. The streams exchange information, build on each other, and come together over time to form an interdisciplinary, integrated effort to realize usable predictive climate information. The framework combines activities within each research stream with integration activities. Integration activities promote information exchange across the streams at key points throughout the framework. Activities within each research stream are responsive to information received from the other stream and return with new information to exchange. The specific activities implemented are summarized in this section, and further details of the research methods are provided under experimental procedures. Over the multi-year time span of the project and multiple sequences of distinct and integrative activities, the research streams become knitted together and proceed as a single interdisciplinary activity. This culminates in the design and production of images of decadal climate predictions that are responsive to our understanding of information needs and simulation capacity and skill. These images form the basis for structured discussions with stakeholders to identify potentially usable image formats and the water management decisions for which they may be appropriate. Our implementation of this framework focused on two case study regions—Colorado and California—that differ by geography, climate, decision contexts, familiarity of managers with predictive climate information, and regulatory and policy environments. For Colorado, we worked with a city drinking-water utility and a regional flood-risk-management organization. Our California stakeholders were a statewide water agency and a coastal county water agency. The framework rests on a bedrock of trust among participants. The first activity is establishing working relationships between stakeholders and scientists facilitated by a trusted partner. In this project Jacobs, a private water resource engineering firm, served as the trusted partner. Jacobs has substantial experience bridging climate science and practice and provided deep knowledge in the application of climate science specific to our chosen water agencies. In addition, Jacobs' history of successful collaborative projects with the water agencies allowed our project to start from a position of trust. But the role of Jacobs did not stop there. Jacobs' expertise in climate and hydrology was also essential to later translate atmospheric predictions into hydrologic predictions that were more directly relevant to stakeholders' information needs for decision-making. And during our final integration activity, Jacobs provided interpretations and infused our group discussions of the images with trust and credibility. Our first activities within each research stream were literature reviews to establish a baseline understanding of the current capabilities of decadal climate prediction science and the current state of use of predictive climate information within water-resource and flood-risk-management decision-making contexts. Our first activity focused on integration was an initial stakeholder-scientist meeting. This meeting served as an initial exchange of information to share foundational knowledge. This included knowledge on stakeholder decision contexts, vulnerabilities of flood-risk and water management to decadal climate variability, and the current state of climate simulation capacity and predictive skill. Following this initial stakeholder meeting, in-depth data collection and analyses were conducted in both research streams. In the climate research stream, statistical and dynamical climate modeling was used to advance process-level understanding of decadal climate at the scales and variables understood as desirable by stakeholders. In parallel, data gathered at the initial stakeholder meeting were analyzed to start to map out potential uses of predictive climate information on decadal timescales. Building on this analysis, additional structured interviews were conducted with stakeholders and the data analyzed to yield more detailed understanding of how multi-year climate information intersects with decision-making and which types of information might be most useful. Rather than occurring as discrete stages, these activities within each research stream proceeded as a continuum, overlapping in time. Here, information exchange occurred informally through small-group discussions of the full research team, including social and climate scientists. Throughout the project, researchers focusing on different activities exchanged emerging knowledge and ideas in small-group and team-wide discussions. This iterative and informal exchange of information allowed the advancing climate science to inform the structure of the interviews and the stakeholder data analysis to inform additional physical science investigations. Through this iterative process we identified potential opportunities to produce usable information, where the credible variables and scales intersect with our understanding of information needs. One example in our project, discussed further below, is the translation of atmospheric prediction to hydrologic prediction. Figure 1 presents the UDECIDE research framework as implemented in this project. For application to other decision contexts or regions, we anticipate that the sequencing of activities, frequency of interactions, and methods may be different. We review our experience with the framework in the discussion, identifying the critical activities and highlighting possible improvements. Here we summarize results of the in-depth data collection and analysis conducted in both research streams as well as the initial stakeholder meeting. We first summarize results on the potential use of decadal-climate information in decisions from analysis of information gathered at the initial stakeholder meeting, combined with data collected through targeted interviews with a larger set of Colorado stakeholders (described in more detail under “Initial stakeholder-scientist meeting” and “In-depth data collection and analysis”). These interviews were informed by the initial meeting and our literature review of current usage of climate information. The interviews were designed to understand in greater detail the individual stakeholders' perspectives on weather and climate characteristics of key concern, including how prediction timescale and geography are considered in decisions. We chose not to conduct interviews with our California stakeholders at this stage because the information gathered at the initial stakeholders meeting was already so rich, and entry points were readily identified. In addition, we were able to leverage our Jacobs team members' ongoing projects with California stakeholders and knowledge to understand these stakeholders' multi-year climate decisions and information needs in more detail. For Colorado, flood risk managers are concerned with flooding from short-duration, intense, local thunderstorms and from longer-duration deluges associated with synoptic-scale weather systems. Current management decisions respond to the immediate pressures of population growth and urbanization. However, a key vulnerability of urban flood infrastructure relevant to the decadal timescale is newly constructed vegetated channels that require an initial 2-year root growth phase free from sustained high-water levels or flash flooding. Such riparian ecosystem corridors are increasingly being used to replace older concrete flood mitigation infrastructure in areas of new urban development. Water resource managers in Colorado are concerned with water supply that is vulnerable to multi-year drought combined with high demand. The drinking-water utility we worked with is a leading expert at integrating climate information into practice and readily identified decisions that project onto the multi-year timescale: infrastructure maintenance, minor infrastructure investments (e.g., culverts), and periodic updates to long-term master plans. For California, the statewide and coastal water agencies have similar responsibilities of water supply and quality, flood and drought management and emergency response, and providing recreational opportunities and fish and wildlife habitats. They are highly sophisticated consumers of weather forecasts, seasonal forecasts, and climate projections and have already explored the use of decadal climate predictions. This allowed us to readily identify a number of potential entry points for useful decadal climate information. The region's precipitation mainly arrives in a small number of intense winter storms,33Dettinger M. Anderson J. Anderson M. Brown L. Cayan D. Maurer E. Climate change and the delta.San Franc. Estuary Watershed Sci. 2016; 14https://doi.org/10.15447/sfews.2016v14iss2art5Crossref Scopus (34) Google Scholar meaning that interannual variability in the number of these storms can produce large swings in annual precipitation.34Dettinger M.D. Ralph F.M. Das T. Neiman P.J. Cayan D.R. Atmospheric Rivers, floods and the water resources of California.Water. 2011; 3: 445-478https://doi.org/10.3390/w3020445Crossref Scopus (590) Google Scholar System-wide flooding and drought can result,34Dettinger M.D. Ralph F.M. Das T.