Surface Water Dynamics in the Amazon Basin:

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2nd International LBA Scientific
Conference Manaus, Amazonas, Brazil, July 7-10,
2002
Surface Water Dynamics in the Amazon Basin
Application of Satellite Radar Altimetry C.M.
Birkett1, L.A.K. Mertes2, T. Dunne3, M.H. Costa4,
M.J. Jasinski5 1ESSIC, Code 923, NASA/GSFC,
Maryland, 20771, USA, cmb_at_nemo.gsfc.nasa.gov 2Depa
rtment of Geography and ICESS, University of
California at Santa Barbara, USA 3Bren School of
Environmental Science and Management and ICESS,
University of California at Santa Barbara,
USA 4Department of Agricultural Engineering,
Federal University of Viçosa, Brazil 5Hydrological
Sciences Branch, NASA/GSFC, Maryland, USA
JGR-Atmospheres LBA Special Issue, 2002
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
NASA Terrestrial Hydrology Program
NASA NRA-98-MTPE-01 Opportunities for
HydroMeteorological Participation in the
Large-Scale Biosphere-Atmosphere Experiment in
Amazonia SH-01 Altimetric Remote Sensing of the
Amazon Contribution to Surface Water
Dynamics Priority Topics Addressed Testing
Remote Sensing algorithms for estimation of
surface state variables Provision of missing
surface data for documentation of regional water
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
1970-1980 GEOS-3, SEASAT 1980-1990 USN
GEOSAT 1990-2002 ESA ERS-1, ERS-2 NASA/CNES
TOPEX/POSEIDON 2002- NASA/CNES JASON ESA ENVISAT
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
ADVANTAGES The contribution of new information
where traditional gauge (stage) data is
absent. Day/night and all weather
operation. Generally unhindered by vegetation
or canopy cover. Determined surface heights
are with respect to one common reference
frame. Repeat orbits (to 1km) enable
systematic monitoring of rivers, lakes, wetlands,
inland seas and floodplains. Surface water
heights are potentially obtainable for any target
beneath the satellite overpass. The ability to
monitor seasonal to inter-annual variations
during the lifetime of the missions.
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
Water-surface gradient Amazon Main stem June 1,
1993-1999
Spatial variability of the average (1993-1999)
water-surface gradient for June 1. Each value
represents the reach between adjacent
TOPEX/POSEIDON satellite crossings. Approximate
location of the axes of arches and buried bedrock
ridges are indicated JAJutai Arch, TFBTilted
Fault Block, PAPurus Arch, MIMonte Alegre
Intrusion and ridge. Distances refer to the
center position between the satellite pass pair.
Seasonal Variation
Temporal variation if altimetric water-surface
gradients for the 1995/1996 season. Error bars
for each date reflect the accuracy of the
altimeter measurements. Distances are to the
mid-point of the satellite pass pair. High water
measurements (March, April, May, July) are
represented by solid symbols. The average high-
and low-water gradients are denoted by solid and
dashed lines respectively. Ground-based velocity
profile measurements were additionally obtained
at 5 gauge locations. Positions of major
tributary inflows are marked.
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski

• RESULTS
• Production of a new data set of surface level
  variations.
• Successful for 30-50 of initial target
  selection.
• Elevation accuracy of tens of centimetres.
• 1km minimum river width with floodplain.
• Main stem amplitudes, peak flows, f.w. velocity
  0.35m/s
• Gradient values 1.5 to 4.0cm/km.
• Main stem gradient spatially and temporally
  variable.

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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
Water Level Changes if a Large Amazon Lake
Measured with Spaceborne Radar Interferometry
and Altimetry, Alsdorf et al., GRL, 2001
Time series of simulated and observed relative
mean monthly water heights above flood stage for
2 locations on the Amazon Mainstem (Coe et al.,
JGR-Atmospheres LBA Special issue).
Balbina reservoir, Uatuma River
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Surface Water Dynamics in the Amazon
Basin Application of Satellite Radar
Altimetry C.M. Birkett L.A.K. Mertes T. Dunne
M.H. Costa M.J. Jasinski
ERS-2 1995-2002
Jason-1
ICESat
ENVISAT