Project II

An Assessment of Decadal Drought Information Needs of Stakeholders and Policymakers in the Missouri River Basin

Funded by:
National Oceanic and Atmospheric Administration – Office of Global Programs – Sectoral Applications Research Program; August 2008 – July 2010

Principal Investigators:
Vikram M. Mehta, CRCES
Norman J. Rosenberg, CRCES

Research Associate:
Katherin Mendoza, CRCES

Michael J. Hayes, National Drought Mitigation Center, Univ. of Nebraska
Cody Knutson, National Drought Mitigation Center, Univ. of Nebraska
J. Rolf Olsen, Institute for Water Resources, US Army Corps of Engineers

Project Summary

Based on our previous research on quantifying impacts of three decadal climate variability (DCV) phenomena; the Pacific Decadal Oscillation (PDO), the tropical Atlantic gradient (TAG) variability, and the Indo-Pacific Warm Pool (WP) variability; on the Missouri River Basin (MRB) hydro-meteorology, water resources, and crop yields, the primary purpose of this project was to widen our pilot exercise to solicit, evaluate, and document users’ DCV-related drought information needs across the entire MRB. In order to achieve this purpose, we undertook systematic assessments of the DCV-related perceptions and drought information needs of various types of stakeholders and policymakers in the MRB for decision support via a series of workshops, surveys, and web-based communication methods. To help demonstrate the relationships between DCV and associated impacts in the MRB, we developed retrospective scenarios for three DCV-related hydrologic events in the MRB; the multiyear-to-decadal drought event in the mid-to-late 1980s and the drought from 2000-01 to 2008, and the multiyear-to-decadal flood event in the 1990s; and their possible impacts on hydro-meteorology, water and crop yields, and regional economy. This work was essential to help provide credibility of the relationships to stakeholders, was useful in fostering discussions on the effects of DCV, and provided a starting point for discussion on the information needed to better understand and effectively adapt to and cope with DCV-related droughts.

This research was conducted via workshops involving over 120 stakeholders and policymakers in the MRB; development of retrospective drought and flood scenarios using statistical modeling of DCV indices and their associations with hydro-meteorological variables in the MRB; and development of sectoral impact evaluations through use of the Hydrologic Unit Model of the United States (HUMUS) and the Erosion Productivity Impacts Calculator (EPIC) driven by the retrospective scenarios. Retrospective scenarios of hydro-meteorological variables, crop yields, and water flows were compared with records of actual hydro-meteorological variables, crop yields, and water flows, and, these results were a part of the DCV-related drought information provided to users in workshops. A dedicated, interactive website and a quarterly newsletter were developed for continuous interactions with the user groups about DCV phenomena and their impacts on the MRB. Although this study was focused on droughts, the methodologies and the expanded network of stakeholders and policymakers developed in the MRB can also be used to assess impacts of floods and related information needs of users.

This study showed that impacts, including economic impacts, of DCV on water and agricultural production in the MRB are identifiable and quantifiable. Stakeholders have clear notions about their needs for decadal climate information and specific suggestions of how these might be met. But, while stakeholders are eager to use climate information, including decadal climate outlooks, there are many potential barriers to their use. The first and foremost barrier is that the credibility of decadal climate outlooks is yet to be established. Secondly, the nature of institutional rules and regulations, laws, and legal precedents that pose obstacles to the use of decadal climate outlooks must be better understood and means to modify these, where possible, must be sought. This study has also shown the need for more quantitative studies of DCV impacts and the need to draw more generalizable and detailed conclusions from such studies.

Major conclusions about stakeholders’ awareness of decadal dry and wet spells, and their societal impacts in the Basin that are substantially and qualitatively different from impacts of seasonal to interannual climate variability; their decadal climate information needs; potential barriers to using decadal climate predictions/outlooks; lessons for climate scientists; and recommendations from stakeholders are described in Mehta et al. (2013).