using remote sensing to estimate water resources from glacial melt
DESCRIPTION
Using Remote Sensing to Estimate Water Resources from Glacial Melt. Prof. Kenneth L. Verosub Dept of Geology University of California, Davis ,. Santiago and its mountains. Rivers of Central Chile. Glacial and Snow Melt. Rivers and glaciers . Rio Cruces discharge record. - PowerPoint PPT PresentationTRANSCRIPT
Using Remote Sensing to Estimate Water Resources
from Glacial Melt
Prof. Kenneth L. Verosub
Dept of GeologyUniversity of California, Davis,
Santiago and its mountains
Rivers of Central Chile
Glacial and Snow Melt
Rivers and glaciers
Rio Cruces discharge record
Center of VolumeSierra Nevada (Calif.)
Spring Fraction of RunoffSierra Nevada (Calif.)
Basic Hypothesis:
Riverflows can be measured using only geospatial imagery.
River Gauge
Rating Curve
An Alternate Approach
Measure the width
River Profile
Use width to determine height from topographic profile.
An Alternate Approach (con’t)
Q = v A
v = c (RS)1/2
Basic flow equation:
where Q is discharge, v is velocity and A is area
Chezy equation:
where c is a constant, R is hydraulic radius and S is the slope of the channel.
Hydraulic radius is the area divided by the wetted perimeter.
c = (1/n) R1/6
Q = (1/n) A R2/3 S1/2
Manning Chezy equation:
Manning equation:
where n is the roughness coefficient.
Note: A, R, and S can be determined from detailed topography or a DEM, and n can be estimated visually.
GeoEye-1
5 spectral bands40 cm resolution (visible)
Commercial
GeoEye: Coliseum in Rome
GeoEye: Kansas City Airport
Obtain topographic maps or DEMs (at low flow) from stereo image pairs, SRTM and/or Lidar.
Determine topographic profile and slope for target site.
Calculate other geometric parameters from width vs. depth relationship.
Use Manning-Chezy Equation (and others) to calculate discharge as a function of width.
Use regular imagery to determine flows at other dates/times.
Basic Methodology
Width vs. Depth
Area (A)PerimeterHydraulic Radius (R)Mean Depth (Ym)
Width (W) vs. Depth
Numerical integration of
to obtain
for any given depth.
Half-width vs. Depth
Q = (1/n) A R0.67 S0.5
Q = 7.1 A Ym0.67 S0.33
Q = 7.22 W1.02 Ym1.74 S0.33
Q = 4.62 W1.17 Ym1.57 S0.34
Bjerklie et al. equation:
Dingman and Sharma equation:
Manning (Bjerklie) equation:
Manning Chezy equation:
Mississippi at Thebes
Mississippi at Thebes
Mississippi at Thebes
Mississippi at Thebes
Width vs. Discharge Curve
6/25/2006
12/27/2003
6/01/2007
3/8/2009
3/18/2006
a
6/4/2010
Cosumnes at Michigan Bar (CA) – Chronological
6/25/2006
12/27/2003
6/01/2007
3/8/2009
3/18/2006
a
6/4/2010
Cosumnes at Michigan Bar (CA) – Sequential
6/4/201032
6/25/20066.4
12/27/20039.7
6/01/20072.7
3/8/200929
3/18/200666
a
Cosumnes at Michigan Bar (CA) – Sequential (II)
a
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Cosumnes at Michigan Bar (CA) – Match-ups
Increase spatial resolution of current monitoring efforts.
Application – Monitoring Rivers
April 2011 precipitation
Measuring flows on the Mississippi River
Increase spatial resolution of current monitoring efforts.
Determine flows for critical times for sites where gauging stations have been lost or abandoned.
Application – Monitoring Rivers
Gauging stations are few and far between
Increase spatial resolution of current monitoring efforts.Determine flows for critical times for sites where gauging stations have been lost or abandoned.
Obtain new flow data from physically inaccessible areas, such as high mountains and deserts.
Obtain new flow data from restricted areas, such as military bases and wilderness areas.
Application – Monitoring Rivers
Mountain runoff is poorly understood.
Increase spatial resolution of current monitoring efforts.Determine flows for critical times for sites where gauging stations have been lost or abandoned.
Obtain new flow data from physically inaccessible areas, such as high mountains and deserts.
Obtain new flow data from restricted areas, such as military bases and wilderness areas.
Combine with Lidar for total “state of the river” analysis.
Application – Monitoring Rivers
“State of the River”
Murray-Darling Basin, Australia
“State of the River”
Murray-Darling Basin
Commission website
“State of the River”
Yellowstone River Basin Lidar
“State of the River”
Yellowstone River Lidar corridor
Application to Chile
Gauging stations in Bio Bio province
Period of dicharge record.
Gracias.