Photo: Karen Frey

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Photo Karen Frey
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Science Applications of the WATER Mission
Concept
Doug Alsdorf The Ohio State University
Seed funding from CNES, JPL, and the Terrestrial
Hydrology Program at NASA
earthsciences.osu.edu/water
alsdorf.1_at_osu.eduwww.legos.ob
s-mip.fr/recherches/missions/water
nelly.mognard_at_cnes.fr
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WATER Participants (09 October 06)
177 Participants from 28 Countries on 5 Continents
Rodrigo Abarca del Rio, Jose Achache, Graeme
Aggett, Mohammad Khaled Akhtar, Doug Alsdorf,
Kwabena Asante, Sima Bagheri, Georges Balmino,
Richard Bamler, Luis Bastidas, Subhashranjan
Basu, Okke Batelaan, Paul Bates, Matt Becker, Ed
Beighley, Philippa Berry, Keith Beven, Mike
Bevis, Charon Birkett, Mark Bishop, Leonid
Bobylev, Mikhail Bolgov, Bodo Bookhagen, Jeff
Booth, Elizabeth Boyer, Robert Brakenridge,
Rafael Bras, Alexander Braun, Andrew Brooks,
Richard Bru, Stephen Burges, Stephane Calmant,
Anny Cazenave, Richard Ciotola, Michael Coe,
Jean-Francois Cretaux, Bruno Cugny, Bob Curry,
Marc De Batist, Biao Deng, Stephen Dery, Reinhard
Dietrich, Remco Dost, Claude Duguay, Victor
Dukhovnyi, Bernard Dupre, Michael Eineder,
Theodore Endreny, Jay Famiglietti, Balazs Fekete,
Naziano Filizola, Andrew Folkard, Bruce Forsberg,
Rick Forster, Georgia Fotopoulos, Peter Gege,
Santiago Giralt, Scott Goetz, Kalifa Goita,
Richard Gross, Jean-Loup Guyot, Andreas Guentner,
Stephen Hamilton, Jim Hamski, Peter Hildebrand,
Simon Hook, Matt Horritt, Martin Horwath, Faisal
Hossain, Paul Houser, Jinming Hu, Cheinway Hwang,
Motomu Ibaraki, Walter Illman, Hiroshi Ishidaira,
Shafiqul Islam, Stephane Jacquemoud, Mike
Jasinski, Eric Jeansou, Ola Johannessen, Joel
Johnson, Natalie Johnson, Hahn Chul Jung,
Essayas Kaba, Jobaid Kabir, Josef Kellndorfer,
Brian Kiel, Yunjin Kim, Wolfgang Kinzelbach, Jean
Klerkx, Toshio Koike, Alexei Kosarev, Andrey
Kostianoy, Pascal Kosuth, Chuck Kroll, Sunil
Kumar De, Xi-Jun Lai, Venkat Lakshmi, Bruno
Lazard, Sergey Lebedev, Brigitte Leblon, John
Lenters, Dennis Lettenmaier, Xu Liang, Peter Luk,
Yaoming Ma, Ian Maddock, Jun Magome, Dushen
Mamatkanov, Ramiz Mammedov, Marco Mancini, Andrew
Marcus, Bryan Mark, Thomas Maurer, Kyle McDonald,
Daene McKinney, John Melack, Yves Menard, Carolyn
Merry, Philip Micklin, George Miliaresis, Bill
Mitsch, Nelly Mognard, Delwyn Moller, Alberto
Montanari, Richard Moore, Andreas Neumann, Stefan
Niemayer, Eni Njoku, Daniel O'Connell, Jonathan
Partsch, Tamlin Pavelsky, Christa Peters-Lidard,
Lasse Pettersson, Al Pietroniro, Bill Plant, Will
Pozzi, Shavkat Rakhimov, Naama Raz Yaseef,
Philippe Renard, Jacques Richard, Ernesto
Rodriguez, Ake Rosenquist, Carlos Saavedra, Stein
Sandven, Frank Schwartz, Frederique Seyler,
Yongwei Sheng, C.K. Shum, Trey Simmons, Murugesu
Sivapalan, Leonard Sklar, Larry Smith, James
Smith, Detlef Stammer, Bob Su, Kuniyoshi
Takeuchi, Ryan Teuling, Julian Thompson, Eric
Thouvenot, Wim Timmermans, Laurent Tocqueville,
Kevin Toomey, Peter Troch, Muhammad Noaman Ul
Haq, Susan Ustin, Nick van de Giesen, Zoltan
Vekerdy, Charles Vorosmarty, Wolfgang Wagner,
Claudia Walter, Matt Wilson, Eric Wood, Ouan-Zan
Zanife, Jianyun Zhang, Tiam Zhang, YunxuanZhou
We welcome you to join and participate in WATER!
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Four Key Points for this Talk

• One
• WATER Science and applications objectives have
  important and immediate impacts.
• Dennis Lettenmaier, Paul Bates, Larry Smith, John
  Melack
• Two
• We do not want to do gauging from space!
• Existing spaceborne concepts do not provide the
  necessary measurements (e.g., imagery, profiling
  altimetry).
• Ernesto Rodriguez
• Three
• Wetlands have complex flow, they are not
  bathtubs
• Four
• The Shuttle Radar Topography Mission is
  demonstrating the hydraulic utility of wide-swath
  measurements

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The WATER Mission
Submitted to NRC Decadal Review Panel,
2005. Alsdorf, D., D. Lettenmaier, J.
Famiglietti, and C. Vörösmarty, GEWEX News, 15,
6-7, August 2005. Cazenave, A., P.C.D. Milly, H.
Douville, J. Benveniste, P. Kosuth, and D.
Lettenmaier, EOS Transactions AGU, 85, 59-60,
2004. Alsdorf, D. and D. Lettenmaier, Science,
1485-1488, 2003. Alsdorf, D., D. Lettenmaier, C.
Vörösmarty, the NASA Surface Water Working
Group, EOS Transactions AGU, 269-276, 2003.
6
from international water programs
Slide courtesy Eric Wood
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United Nations 2004 Decides that the goals of
the Decade should be a greater focus on water
related issues at all levels and on the
implementation of water-related programmes and
projects
OSTP OMB 2004
The ability to measure, monitor, and forecast
the U.S. and global supplies of fresh water is
another high-priority concern.
www.whitehouse.gov/omb/memoranda/fy04/m04-23.pdf
www.ostp.gov/html/budget/2007/ostp_omb_guidancemem
o_FY07.pdf
www.ostp.gov/NSTC/html/swaqreport_2-1-05.pdf
www.un.org/Depts/dhl/resguide/r58.htm
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Water Balance Surface Water Virtual
MissionDennis Lettenmaier
Runoff (mm/day)
1.25 1.00 0.75 0.50 0.25 0.00
REAN2 NCEP/DOE AMIP Reanalysis II GSM, RSM
NCEP Global and Regional Spectral Models ETA
NCEP Operational forecast model OBS Observed
J F M A M J J
A S O N D
OBS
REAN2
RSM
ETA
GSM
How does this lack of measurements limit our
ability to predict the land surface branch of the
global hydrologic cycle? e.g., In locations
where gauge data is available, weather and
climate model predictions of precipitation and
subsequent runoff miss streamflow by 100 the
question is unanswered for ungauged wetlands,
lakes, and reservoirs throughout the world.

• Mouth of Mississippi both timing and magnitude
  errors (typical of many locations).
• Within basin errors exceed 100 thus gauge at
  mouth approach will not suffice.
• Similar results found in global basins

Roads et al., GCIP Water and Energy Budget
Synthesis (WEBS), J. Geophysical Research, 2003.
Lenters, J.D., M.T. Coe, and J.A. Foley, Surface
water balance of the continental United States,
1963-1995 Regional evaluation of a terrestrial
biosphere model and the NCEP/NCAR reanalysis, J.
Geophysical Research, 105, 22393-22425, 2000.
Coe, M.T., Modeling terrestrial hydrological
systems at the continental scale Testing the
accuracy of an atmospheric GCM, J. of Climate,
13, 686-704, 2000.
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Needs for Understanding Flooding DynamicsPaul
Bates

• Flooding imposes clear dangers, but the lack of
  water heights and inundation mapping during the
  passage of the flood wave limit important
  hydraulic modeling that would otherwise predict
  the zones of impact.
• Essentially, can we predict flooding hazards
  which could be used to understand the
  consequences of land use, land cover, and
  climatic changes for a number of
  globally-significant, inhabited floodplains?

China
Prague
Estimated Costs 1.9 Billion Over 100 dead in
Europe, alone
Black Sea
Kentucky
India
These are the global floods from 2002, alone!
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Arctic Hydrology and Climate Change, Larry Smith
Smith et al., Science, 2005
L. Smith AGU 2005 Frontier Lecture
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Wetland Dynamics and Carbon FluxesJohn Melack
What is the role of wetland, lake, and river
water storage as a regulator of biogeochemical
cycles, such as carbon and nutrients? e.g.,
Rivers outgas as well as transport carbon.
Ignoring water borne C fluxes, favoring
land-atmosphere only, yields overestimates of
terrestrial C accumulation
Results 470 Tg C/yr all Basin 13 x more C by
outgassing than by discharge. But what are
seasonal and global variations? If extrapolate
Amazon case to global wetlands, 0.9 Gt C/yr, 3x
larger than previous global estimates Tropics
are in balance, not a C Sink?
Richey, J.E., J.M. Melack, A.K. Aufdenkampe, V.M.
Ballester, and L.L. Hess, Outgassing from
Amazonian rivers and wetlands as a large tropical
source of atmospheric CO2, Nature, 416, 617-620,
2002.
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Trans-Boundary Issuesex Tigris Euphrates
Disputes

• Water Usage
• 98.5 water in Euphrates from Turkey Syria
  totally dependent Iraq heavily dependent
• Upsetting the Status Quo
• 1977 Turkey launched Southeastern Anatolia
  Project (GAP) 22 dams 19 hydroelectric power
  plants
• Irrigation will use 27 of total flow (25 km3)
• Tensions raised by unilateral development of
  basins
• Project effectively controls both rivers
• Remote measurements of surface water volumes and
  fluxes creates free information for all, removing
  questions regarding who has how much.

Slide courtesy Frank Schwartz
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Measurements Required to Address Science
Applications Themes h, ?h/?x, ?h/?t, and area,
globally, on a weekly basis
Muskingum R., Ohio
Continuity Equation

Q

h
q

L

x

t
A Typical Flow Law

( )
h
1/2
2/3
A
R

x
Q

Siberian Arctic
n
A cross sectional area R wetted
perimeter Both can be mapped over time with
repeated h measurements
?S S ?h/?t
Photos B. Kiel, K. Frey
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Problems with 1D Stream Gauge Measurements
Amazonian wetlands are 750,000 km2
Alaskan braided river
K. Douce Photo
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Lack of Existing Measurements

• Lake Calado The only flood-plain lake, of
  8000, where water balance has been measured
  throughout annual hydrograph.
• 7 Gauges on channels, how do they define flow
  across floodplain? Ita to Man 12,000 inundated
  km2 1/2 Maryland, 634 USGS gauges, Potomac at
  D.C. 400 m3/s Negro40000 m3/s
• Worlds largest river, yet Q and DS are poorly
  known.

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Gauging from Space ? WATER
OSTP 2004 Does the United States have enough
water? We do not know. What should we do? Use
modern science and technology to determine how
much water is currently available
Amazon 6 M km2, 175,000 m3/s U.S. 7.9 M km2,
Mississippi 17,500 m3/s
Birkett, C.M., L.A.K. Mertes, T. Dunne, M.H.
Costa, and M.J. Jasinski,Journal of Geophysical
Research, 107, 2003. Hirsch, R.M., and J.E.
Costa, EOS Transactions AGU, 85, 197-203, 2004.
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Targets are Global
Congo River Basin 3.7M km2
Matthews, E. and I. Fung, GBC, 1, 61-86, 1987.
Ohio R.
Canada
Floods
Peace-Athabasca Delta 3200 km2
New Orleans
Costa Rica
Reservoirs Worldwide
Braided Rivers
Coastal Zones
Alaska
N. Korea
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Conventional Idea of Floodplain Inundation
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Measurements of Floodplain Inundation
Localized, complex patterns of dh/dt Sharp dh/dt
aligned with many channels Purus flood wave is
apparent
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Flow Directions Estimated from Continuity
Localized, complex patterns of dh/dt with sharp
dh/dt aligned with many channels indicates flow
to floodplain arriving via channels and emptying
to one side. Purus flood wave supplies water.
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Measurements of Floodplain Inundation
Broad, simpler patterns of dh/dt Sharp dh/dt
aligned with fewer channels Amazon flood wave is
apparent
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Flow Directions Estimated from Continuity
Broad, simpler patterns of dh/dt with sharp dh/dt
aligned along fewer channels implies diffuse flow
across entire floodplain. Amazon flood wave
supplies water.
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There are hundreds of thousands of reservoirs and
lakes around the world, but their storage changes
are poorly known (even in the U.S.!). Space
shuttle radar data measured water elevations in
reservoirs surrounding Columbus. The topography
image on the left was collected by the space
shuttle in February 2000 whereas the plot below
shows the water surface elevations for Hoover
Reservoir. The change in elevations (blue dots
compared to red dots) agree with the height of
the dam, but the elevation standard deviation for
each height measurement is 5.71 m. Improvement
in measurement accuracy is needed, but the data
suggest a great opportunity for a future
satellite mission.
Hoover Reservoir
Kiel, Alsdorf, LeFavour, PE RS, 2006
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Purus River Measured Width
Mannings n method
Width algorithm developed by Tamlin Pavelsky, UCLA
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Purus River SRTM Estimated Discharge
Based on in-situ gauge data, discharge in this
Purus reach is estimated at 8500 m3/s (no
February 2000 data is available, estimate based
on previous years).
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Channel Slope and Amazon Q from SRTM
Water Slope from SRTM
Q m3/s Observed SRTM Error Tupe 63100 62900 -0.3
Itapeua 74200 79800 7.6 Manacapuru 90500 84900 -6
.2
Channel Geometry from SAR
Bathymetry from In-Situ
Mannings n method
LeFavour and Alsdorf, GRL, 2005 Kiel et al.,
PERS, 2006
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In February 2000, the Space Shuttle collected
radar-based elevation measurements around the
globe. Elevations of water surfaces can be
converted to river flow using empirical equations
that relate water slope to flow velocity. This
plot shows the discharge of the Ohio River during
the two-week Shuttle Mission and is the
first-ever mapping of its type!
Ohio R. Q, Brian Kiel, OSU
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Spatial Resolution is A Key Cost Driver for WATER

• Freshwater requires higher spatial resolution
  than the original WSOA concept
• Results in a greater power need and a higher data
  rate
• Ernesto Rodriguez and Tony Freeman will address
  these issues
• the following provides a simple example
• Entire Earth surface is 510,100,000 sq km
• 148,300,000 sq km is terrestrial, 29.1
• 361,800,000 sq km is ocean, 70.9
• Removing Antarctica, Greenland, the islands
  around northernmost Canada, Sahara, Gobi, and
  Australia, leaves a resulting land area of 22
• 22 112,220,000 sq km of land surface where
  WATER may need to acquire high resolution data
• Resulting end-member land coverages assuming
  various nominal range by azimuth resolutions
• resolution of 2m x 30m
• All land surfaces 2470 gigapixels per global map
• 22 land surfaces 1870 gigapixels per global map
• resolution of 8m x 30m
• All land surfaces 620 gigapixels per global map
• 22 land surfaces 470 gigapixels per global map
• resolution of 16m x 50m
• All land surfaces 185 gigapixels per global map
• 22 land surfaces 140 gigapixels per global map

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Goal To determine where water is stored on
Earths land surfaces, and how this storage
varies in space and time.

• Global Problem
• Fresh water bodies cover at least 4 of Earths
  terrestrial surface whereas tropical wetlands,
  particularly in the Amazon Basin, occupy nearly
  20 of their watershed, The vast storage capacity
  of wetlands, reservoirs, rivers, etc. impact the
  global water cycle.
• Remote Problem
• Amazon, Congo, Arctic, etc. are physically remote
  and other areas are politically remote.
• Physics of Water Flow
• WATER is not a gauge replacement strategy, rather
  it is an altogether new way of understanding
  water storage and flow. Water fluxes and volume
  changes are more than a 1D process.
• No Satellite Available
• Profiling altimeters repeat 1D, in-situ gauge
  approaches whereas WATERs KaRIN will provide
  two-dimensional h, dh/dt, and dh/dx about once a
  week, thus yield ?S and Q globally.
• Free Data For All Nations
• Free access to data will enable all governments
  to know how much surface water they have.