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Purdue University Winter Hydrology and Erosion Research. Keith A Cherkauer, Dazhi Mao, Tushar Sinha Agricultural and Biological Engineering Jeff Evans Electrical and Computer Engineering Technology. Outline. Field measurements Historical analysis Watershed scale simulations
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Purdue University Winter Hydrology and Erosion Research Keith A Cherkauer, Dazhi Mao, Tushar Sinha Agricultural and Biological Engineering Jeff Evans Electrical and Computer Engineering Technology
Outline • Field measurements • Historical analysis • Watershed scale simulations • Basin scale simulations • Land use change • Climate change
Field Observations Spring 2000, Vermillion River, Minn.
5 cm Soil Thaw Dates:Winter 1998-1999 Last Day of Frozen Soil, 1999
Current Field Measurements • Self contained units • 10 locations – 2 per field type • 10 and 20 cm depths • Temp and Moisture • Field surveys • Wireless sensor network
Historic Analysis • Soil temperature observations from mid-1960’s • Early records must be digitized
Pinney-Purdue Agricultural Center (PPAC) near Wanatah Soil – Tracy sandy loam Agronomy Center for Research and Education (ACRE) near West Lafayette Soil – Russell silt loam Study Area Southern Indiana Purdue Agricultural Center (SIPAC) near Dubois Soil – Zanesville silt loam Soil temperature data collecting station (since 1966)
Annual Average Statistics *SIPAC average statistics estimated from 1985 - 2004
Average statistics for selected soil frost variables. PPAC – Annual snowfall (107.8 cm), Soil – Tracy sandy loam ACRE – Annual snowfall (53.9 cm), Soil - Russell silt loam SIPAC – Annual snowfall (23.2 cm),Soil – Zanesville silt loam
Selected Surface Variables PPAC ACRE SIPAC
Bare soil at 5 cm soil depth ACRE PPAC SIPAC
Watershed Scale Simulations Distributed Hydrology-Soil-Vegetation Model (DHSVM) • Physically based hydrologic model that represents the effects of • Topography • Soil • Vegetation • Solves the energy and water balance at each grid cell at each timestep
Q Qsed Erosion and Sediment Transport Module MASS WASTING Soil Moisture Content Sediment Channel Flow Sediment DHSVM Precipitation Leaf Drip Infiltration and Saturation Excess Runoff CHANNEL ROUTING Erosion Deposition HILLSLOPE EROSION ROAD EROSION
Current land holdings: 80% Yellowwood State Forest 20% - 55 private owners Legacy of intensive agriculture “experiment” in early 1900’s Highly eroded hill-sides Large alluvium storage? Yellowwood Lake Watershed Source: National Land Cover Data (NLCD) 2001
Cumulative Erosion Erosion/Deposition (m)
Basin Scale Simulations Variable Infiltration Capacity (VIC) Hydrology Model • Mosaic Type Land-use • Variable Infiltration Curve • Arno Baseflow Curve • Full surface energy balance • Full water balance
VIC Model Snow Algorithm • 2 Layer Ground Snowpack • Full Energy Balance with Thin Surface Layer • Heat Exchange with Ground Surface • Canopy Interception • Wind Profiles From DHSVM
VIC Model Frozen Soil Algorithm • Heat and moisture fluxes solved independently • Bottom boundary • Constant Temperature • Constant Flux • Permafrost capable Cherkauer and Lettenmaier, 1999
Distributed Frozen Soil Temperature Distribution Ice Content Distribution
WEPP model 30 arc-sec DEM ArcGIS Daily climate forcing 30m DEM Soil & vegetation Hourly precipitation Slope profile Adjusted erodibility, friction factors, & random roughness VIC Precipitation & runoff output WEPP-HE Code Soil loss - original input data - intermediate data - data for WEPP-HE - data processing Iterated for sampled slopes - iterated process VIC-WEPP Coupled Model
Upper Mississippi River:Average Annual Mean Frost Depth Spring Winter
Upper Mississippi River:Annual Average Spring 10 cm Soil Moisture
West Lafayette – Bare Soil (10 cm) Damping Depth = 10 m No. of Nodes = 8
Climate Change Simulations • Three models • Gfdl • Hadcm3 • Pcm • Two senarios • A1fi – rich and poor equalize, intensive fossil fuel use • B1 – Disparity between rich and poor increases
Bare soil at 10 cm soil depth ACRE PPAC SIPAC