1. Predicting the hydrologic and water quality implications of climate and land use change in forested catchments
Dennis P. Lettenmaier
Department of Civil and Environmental Engineering
University of Washington
Joint UW/Cimate Impacts Group – NW Fisheries Science Center Meeting
June 12, 2003
Seattle

4. VIC Simulations of April 1 Average Snow Cover Extent
MPI ECHAM4 Scenarios
~2025
~2045
Base Case

6. Changes to Mean Hydrographs Columbia Basin 2045

7. ColSim Reliability of System Objectives

8. DHSVM basics Physically based hydrologic model Grid based (DEM)
Two layer canopy for vegetation
Simultaneously solves energy and water balance

10. DHSVM Input and Output DEM Met. data Vegetation
(type, LAI, height, etc.)
Soil texture
Soil depth
Critical
shear
stress
DHSVM
Critical
soil
moisture
Soil moisture
Overland flow
Channel flow

11. Mass Wasting Module Multiple realizations of total failure locations
Multiple time series
of sediment supply
Soil depth
DEM
Soil info
Vegetation info
P(F)
MASS WASTING

12. Surface Erosion Module
Soil
Precipitation
Vegetation
DEM
Multiple time series
of sediment supply
Overland flow
SURFACE EROSION
Distribution of
sediment delivery
to channels
(roads and streams)
Roads and streams

13. Channel Erosion Module
Channel flow
CHANNEL
EROSION
Mean and standard
deviation of sediment
load for selected channel
reaches
Distribution of
sediment delivery
to channels
(roads and streams)

14. Watershed Sediment Module validation suggestions
Mass wasting
Regional land slide frequency and extent over a multiyear period derived from ground-based mapping, remote sensing or aerial photography
Surface erosion
Compilation of regional observations of land surface and road surface erosion rates
Channel routing
Observed stream discharge and sediment concentrations over a multiyear period

15. Probability of slope failure before and after Fourth of July Fire
Pre-fire
Approximate
extent of August
2001 fire
Post-fire
Icicle Creek Vegetation