HR: 12:05h
AN: H22C-08 INVITED     [Abstracts]
TI: Measuring Surface Water From Space
AU: * Rodriguez, E
EM: ernesto.rodriguez@jpl.nasa.gov
AF: Jet Propulsion Laboratory/California Institute of Technology, MS 300-319 4800 Oak Grove Dr., Pasadena, CA 91109 United States
AU: Moller, D
EM: delwyn.moller@jpl.nasa.gov
AF: Jet Propulsion Laboratory/California Institute of Technology, MS 300-319 4800 Oak Grove Dr., Pasadena, CA 91109 United States
AB: The requirements for the measurement of surface water from space have been reviewed by Alsdorf and Lettenmaier (Science, 301, 2003). These requirements include monitoring the water level to centimetric accuracy with a spatial resolution on the order of 100 meters; imaging of fresh water bodies with a similar spatial scale; determining the slope rivers with an accuracy of about 1cm/1km; temporal sampling which varies from weekly, for arctic rivers, to a few weeks, for tropical rivers like the Amazon. In this work, we review the ability current remote sensing technology to meet these requirements. Among the technologies examined will be radar altimeters, such as the NASA TOPEX altimeter, lidars, such as IceSat, and interferometric radars, such as SRTM or the forthcoming Wide-Swath Ocean Altimeter. We conclude in our study that the requirement for suitable temporal and spatial coverage of heights leads to a choice of either a swath instrument or a constellation of nadir profiling instruments. If, in addition, one requires co-registered delineation of water bodies and water topography plus the ability to observe through clouds, only an interferometric radar system is currently able to meet all of the desired science requirements. In the final part of this study, we present a design for a Ka-band interferometric system which is feasible with currently available technology and which has been optimized for the measurement of surface water. We discuss in detail the error sources and calibration of such an instrument. We also present a mission and orbit scenario capable of meeting the stringent space time sampling requirements detailed above. Finally, we present the results of an instrument simulator which is able to produce data typical of what could be obtained from a spaceborne mission and demonstrate the measurement capabilities over realistic river drainages.
DE: 1894 Instruments and techniques
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting