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Catchments Lump Processes. Emergent Behavior. Recent work has identified many Physically Lumped Properties that are manifestations of the system of states and fluxes -A physical basis for lumped parameter modeling.
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Catchments Lump Processes Emergent Behavior Recent work has identified many Physically Lumped Properties that are manifestations of the system of states and fluxes -A physical basis for lumped parameter modeling Decades of case studies have documented the many ways that water moves downhill
Physically Lumped Properties(emergent behavior) • Connectivity • See papers by • Western and Grayson • McGlynn • McNamara • Stieglitz • Pringle • April James • Talk by McNamara • http://a-c-s.confex.com/crops/2010am/webprogram/Paper61589.html
Physically Lumped Properties • Thresholds • See papers by • McNamara • McGuire • McDonnell • Many others
Threshold responses 1 Satellite Tarrawarra Runoffratio 0 0 10 20 30 40 50 Moisture content (%) Courtesy of Roger Grayson Roger Grayson, pers. Com.
Physically Lumped Properties • Residence Time • See papers by • Tetzlaff, Soulsby • McGuire • McDonnell
C ( t ) in ( t ) C out Figure from Jim Kirchner This approachsimplified
Model Theory: The Convolution Integral Predicted or simulated output d18O signature Input Function: Derived from precipitation d18O signal Represents d18O in water that contributes to recharge System Response Function: Time distribution of water flow paths
Precipitation Soil Water d18O‰ Soil water Residence Time -4 -8 -12 -16 -4 -8 -12 -16 d18O‰ Average -9.4‰ Amplitude 0.1‰ Std Dev. 3.4 ‰ Average -9.4‰ Amplitude 1.2‰ Std Dev. 0.6 ‰ Annual Data P 2250 mm Q 1350 mm E 850 mm Average Data Slope 34o Relief 100-150m Ksat 5 m/hr Soils Data Depth 1 m Strong catenary sequence Soil water residence time
If bedrock quite impermeableMRT and distance from the divide Vache and McD WRR 2005
Storage in Hydrologic Modeling • Review • Classic linear and non-linear reservoir modeling • Semenova model • Kirchner model