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Adaptation Strategies for Freshwater Ecosystems in the Pacific NW. 2009 WWF Science for Nature Symposium. Allison Aldous & Leslie Bach, The Nature Conservancy. photo © Rick McEwan. © Rick McEwan. © Laura Moran. © Rick McEwan. # GDEs 5 4 3 2 1.
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Adaptation Strategies for Freshwater Ecosystems in the Pacific NW 2009 WWF Science for Nature Symposium Allison Aldous & Leslie Bach, The Nature Conservancy photo © Rick McEwan
# GDEs 5 4 3 2 1 Distribution of groundwater-dependent ecosystems Brown et al. 2009
Fish kills National wildlife refuge dewatering Surface water eutrophication Salmon fisheries closures
Current solutions • Habitat restoration • wetlands • streams • riparian areas • Klamath Basin Restoration Agreement • Remove 4 dams • Retire some irrigation water rights • Reliable water allocation for agriculture
Salathé 2007 • Not Always Practical • Availability of downscaled climate models • Availability of time series data • Expertise, resources • High level of uncertainty • GCMs • downscaling • hydrologic models • freshwater ecosystems responses Hamlet et al. 2008 Tague et al. 2008
Snowmelt-dominated Groundwater + snowmelt Groundwater-dominated
Snowmelt dominated hydrology total snowpack Loss of snowpack Higher Temperatures Rise in freezing elevation High elevation Mid-elevation Courtesy T. Beechie • more winter rain • earlier snowmelt • more rain-on-snow events • earlier summer low flow • lower summer baseflow Low elevation
less snowpack + earlier runoff + higher elevation snow zone + higher ET = less recharge + warmer recharge + less, warmer discharge adapted from Vaccaro 2008. Groundwater-dominated hydrology mountain-front floodplain / wetland spatially distributed Winter et al. 1998
Winter precip ↑ 17% baseflow ↓ 20% Hydrograph shifts by 15 days
Adaptation options for snowmelt-dominated hydrology • Factor changing water availability into settlement agreement • Land management in the snowpack zone • Increase water storage in ecosystems • wetland/riparian protection & restoration • reconnect channels with their floodplains Temp Loss of snowpack
Adaptation options for groundwater-dependent ecosystems • Factor changing water availability into settlement agreement • Land management in the snowpack zone • Wetland/riparian protection & restoration • Reconnect channels with their floodplains • Set environmental water requirements for groundwater mountain-front floodplain / wetland spatially distributed Winter et al. 1998
How is this different? • Anticipate future water availability • Emphasis on groundwater recharge • Emphasis on mid-elevation snowpack • Prioritize water storage in ecosystems