Post on 14-Feb-2016
description
Flow prediction accuracy given DEM resolution
Model accuracy for snow-rain transition watersheds was more sensitive to DEM resolution than for snow-dominated watersheds.
Model accuracy for watersheds with steep slopes was more sensitive to DEM resolution than for watersheds with mild slopes.
Model accuracy in general is higher for snow dominated watersheds. K.Son, Tague. C and , Hunsaker, C.T, (in prep) Effect of spatial resolution of DEM on ecohydrologic predictions and its sensitivity to climate variability in Sierra mountain catchments, Water resources Research.
Soil parameter uncertainty effectvs. climate warming effect
TMS(P301)
SMS(B203)
Soil parameter uncertainty effect was larger than climate warming effect.The climate warming effect was larger in the wetter climate conditions K. Son and Tague, C. (in prep) Importance of soil parameter uncertainty in assessing climate change projections in small two Sierra watersheds,
Water resource research
Calibrated RHESSYs model
Generated Spatial and temporal values of snow, soil moisture and transpiration
Snow Soil moisture
Transpiration
Clustering analysis (PAM algorithm)
Hydrologic Similarity indices (HSI)
Finding Clusters and Medoids Sampling Recalibrated model
Snow, Soil moisture, Transpiration,
ET and Streamflow
Hydrologic Similarity indices (HSI)mean and inter-annual variation (expressed
as coefficient of variation, CV) of five indicators
(1) Day of water year that snow melts completely (2) Number of days that root-zone soil
moisture is fully saturated (3) Number of days that root-zone soil
moisture declines to 70% of saturation
(4) Number of days that root-zone soil moisture declines to 50% of saturation
(5) Day of water year that transpiration declines to 50% of its peak growing season value
What are strategic soil moisture sampling design to represent the impact of climate variability on soil moisture and vegetation water use in snow-dominated watersheds?
Validation of sampling design
Combining all indices represent elevation difference and the flow drainage pattern. Model-based clusters reproduced general spatial pattern of observed soil moisture. K.Son, Tague, C. (in prep) Strategic sampling microclimate, soil moisture and sapflux for improving ecohydrological predictions
of the Sierra Mountain watersheds., Hydrological Processes
C2
C3
C4
C5
C6C1
With a warmer climate (+3°C) and no change in precipitation – we get increased water demand (Forest ET/NPP should stay the same or increase) – but also a shift in timing (ET/NPP might go down because more winter P is lost as runoff )
Note that the effect of timing occurs across all P, but is greater in wetter years, but also biggest increases occur in the wettest years
Precip PkSwe Interaction
Cont
rol o
n ET
(reg
ress
ion)
Soil parameter uncertainty changes strength of relationships - but not conclusions about importance of precipitation, timing, and their interaction
Tague, C., and H. Peng (2013), The sensitivity of forest water use to the timing of precipitation and snowmelt recharge in the California Sierra: Implications for a warming climate, J. Geophys. Res. Biogeosci., 118, doi:10.1002/jgrg.20073
For all patches, all years, change in ET
Chan
ge in
ET
(war
min
g) (m
m/y
r)