Hydroclimate Variability in Snow-Fed River Systems: Local Water Managers’ Perspectives on Adapting to the New Normal

Abstract

AbstractBetween water years 2012 and 2017, the Truckee–Carson river system in the western United States experienced both historic-low and record-high Sierra Nevada snowpack, anomalously warm temperatures, and winter and spring flooding. As part of an ongoing collaborative modeling research program in the river system, researchers conduct annual interviews with key local water managers to characterize local climate adaptation strategies and implementation barriers, and identify science information needs to prioritize ongoing research activities. This article presents new findings from a third wave of interviews conducted with the same water managers following the historic 2017 wet year. Comparison of these data suggests that managers increased their adaptation efforts described during previous consecutive drought years (2015 and 2016). In 2017, comparatively fewer managers described climate uncertainty as an implementation barrier, exemplifying recent hydroclimate variability as the “new normal” climate for which they should plan. An assessment of recent conditions reveals that recent water years bound historical observations and are consistent with estimated paleoclimate extremes in terms of magnitude, but not persistence, of both dry and wet conditions. Comparison to projected future climate conditions affirms managers’ perspectives that increased hydroclimate variability, inclusive of drought and flood extremes, defines the new normal climate anticipated for the region. To support long-term adaptation planning, managers requested that researchers prioritize simulations of alternative water management strategies that account for nonstationary climate patterns and quantify implications system-wide. This article illustrates how interdisciplinary research that integrates local knowledge with applied climate science research can support adaptive water management in snow-fed river systems.