Abstract:
This paper describes the calibration of the CryoSat-2 interferometer, whose principal purpose is to accurately measure the height of the Antarctic and Greenland ice sheet...Show MoreMetadata
Abstract:
This paper describes the calibration of the CryoSat-2 interferometer, whose principal purpose is to accurately measure the height of the Antarctic and Greenland ice sheets. A sequence of CryoSat-2 data acquisitions over the tropical and midlatitude oceans were obtained between June and September 2010, from the SIRAL “A” and redundant SIRAL “B” radars operating in their “SARIN” mode, during a sequence of satellite rolls between -0.6° and 0.4°. Using the arrival angle of the echo relative to the interferometer baseline, the attitude of the satellite determined by the star trackers, and estimates of the ocean surface across-track slope from the EGM08 geoid, we determined the errors in the interferometer estimate of surface slope as functions of the roll angle and ocean surface waveheight. These were found to be in close agreement with the theoretical description. The scale factor of the interferometric measurement of angle was determined to be 0.973 ± 0.002. We estimate the accuracy of the across-track slope measurement of the interferometer by applying this scale factor to the measured phase. In applying this scale factor to the measurements, the across-track slope of the marine geoid was obtained with an accuracy of 26 μrad at 10 km and 10 μrad at 1000 km. We conclude that the instrument performance considerably exceeds that needed for the accurate determination of height over the sloping surfaces of the continental ice sheets. The results also demonstrate that CryoSat-2 provides the first observations of the instantaneous vector gradient of the ocean surface, and that the normal-incidence interferometric configuration has a greater potential for the measurement of the ocean across-track slope than has been previously recognized.
Published in: IEEE Transactions on Geoscience and Remote Sensing ( Volume: 51, Issue: 1, January 2013)
Center for Polar Observation and Modelling, Department of Earth Sciences, University College London, London, UK
Natalia Galin (M'02) received the B.Eng. degree in electrical engineering from the University of New South Wales, Sydney, Australia, in 2006 and has submitted her Ph.D. thesis “Snow Thickness Estimation Over Antarctic Sea Ice Using Helicopter Borne 2–8 GHZ FMCW Radar” to the University of Tasmania, Tasmania, Australia.
In 2009, she was a Visiting Postgraduate Fulbright Scholar at NASA/Goddard Space Flight Center, Greenbelt...Show More
Natalia Galin (M'02) received the B.Eng. degree in electrical engineering from the University of New South Wales, Sydney, Australia, in 2006 and has submitted her Ph.D. thesis “Snow Thickness Estimation Over Antarctic Sea Ice Using Helicopter Borne 2–8 GHZ FMCW Radar” to the University of Tasmania, Tasmania, Australia.
In 2009, she was a Visiting Postgraduate Fulbright Scholar at NASA/Goddard Space Flight Center, Greenbelt...View more
Center for Polar Observation and Modelling, Department of Earth Sciences, University College London, London, UK
Duncan J. Wingham received the B. Sc. degree in physics from the University of Leeds, Leeds, U.K., in 1979, and the Ph.D. degree in physics from the University of Bath, Bath, U.K., in 1984.
He joined the University College London (UCL) in 1986, where he held lecturing posts at the Mullard Space Science Laboratory and the Department of Electronic and Electrical Engineering. He was appointed to a Chair in the Department of S...Show More
Duncan J. Wingham received the B. Sc. degree in physics from the University of Leeds, Leeds, U.K., in 1979, and the Ph.D. degree in physics from the University of Bath, Bath, U.K., in 1984.
He joined the University College London (UCL) in 1986, where he held lecturing posts at the Mullard Space Science Laboratory and the Department of Electronic and Electrical Engineering. He was appointed to a Chair in the Department of S...View more
VEGA Space GmbH, Hertfordshire, UK
Robert Cullen received the B. Sc. degree in electrical engineering from the University of Hull, Hull, U.K., the M.Sc. degree in satellite communications and spacecraft technology from the University College London (UCL), Surrey, U.K., and the Ph.D. degree in geophysics from the University of Aston, Birmingham, U.K.
He joined the Department of Space and Climate Physics at UCL, in 1998, where he worked on ESA EnviSAT and Cry...Show More
Robert Cullen received the B. Sc. degree in electrical engineering from the University of Hull, Hull, U.K., the M.Sc. degree in satellite communications and spacecraft technology from the University College London (UCL), Surrey, U.K., and the Ph.D. degree in geophysics from the University of Aston, Birmingham, U.K.
He joined the Department of Space and Climate Physics at UCL, in 1998, where he worked on ESA EnviSAT and Cry...View more
New Tech Center, Reah System s, a., Louvain-la-Neuve, Belgium
Marco Fornari (M'09) received the M.Sc. degree in telecommunications engineering from the University of Rome “La Sapienza,” Rome, Italy, in 2006.
Following which, he joined ESA-ESTEC, Noordwijk, The Netherlands, as a Young Graduate Trainee, working on the CryoSat airborne campaigns. In 2007, he received a contract position at ESTEC, joining the CryoSat-2 project as the SIRAL Calibration Engineer. He is currently working at...Show More
Marco Fornari (M'09) received the M.Sc. degree in telecommunications engineering from the University of Rome “La Sapienza,” Rome, Italy, in 2006.
Following which, he joined ESA-ESTEC, Noordwijk, The Netherlands, as a Young Graduate Trainee, working on the CryoSat airborne campaigns. In 2007, he received a contract position at ESTEC, joining the CryoSat-2 project as the SIRAL Calibration Engineer. He is currently working at...View more
National Oceanic and Atmospheric Administration, Silver Spring, MD, USA
Walter H. F. Smith received the B. Sc. degree in geological sciences from the University of Southern California, Los Angeles, in 1984, and the M.A. and Ph.D. degrees in marine geophysics from the Lamont Geological Observatory of Columbia University, Palisades, NY.
From 1990 to 1992, he was a Cecil and Ida Green Scholar in the Institute for Geophysics and Planetary Physics at the Scripps Institution of Oceanography, La Joll...Show More
Walter H. F. Smith received the B. Sc. degree in geological sciences from the University of Southern California, Los Angeles, in 1984, and the M.A. and Ph.D. degrees in marine geophysics from the Lamont Geological Observatory of Columbia University, Palisades, NY.
From 1990 to 1992, he was a Cecil and Ida Green Scholar in the Institute for Geophysics and Planetary Physics at the Scripps Institution of Oceanography, La Joll...View more
Research Department, ECMWF, Reading, UK
Saleh Abdalla received the B. Sc. degree in civil engineering from Kuwait University, Kuwait City, Kuwait, in 1983, and the M.Sc. and Ph.D. degrees in coastal engineering from the Middle East Technical University, Ankara, Turkey, 1986 and 1991, respectively.
He continued to work as an Instructor and then as an Associate Professor. He joined the research Department of European Centre for Medium-Range Weather Forecasts, in 2...Show More
Saleh Abdalla received the B. Sc. degree in civil engineering from Kuwait University, Kuwait City, Kuwait, in 1983, and the M.Sc. and Ph.D. degrees in coastal engineering from the Middle East Technical University, Ankara, Turkey, 1986 and 1991, respectively.
He continued to work as an Instructor and then as an Associate Professor. He joined the research Department of European Centre for Medium-Range Weather Forecasts, in 2...View more
Contents Center for Polar Observation and Modelling, Department of Earth Sciences, University College London, London, UK
Natalia Galin (M'02) received the B.Eng. degree in electrical engineering from the University of New South Wales, Sydney, Australia, in 2006 and has submitted her Ph.D. thesis “Snow Thickness Estimation Over Antarctic Sea Ice Using Helicopter Borne 2–8 GHZ FMCW Radar” to the University of Tasmania, Tasmania, Australia.
In 2009, she was a Visiting Postgraduate Fulbright Scholar at NASA/Goddard Space Flight Center, Greenbelt, MD. She now holds a research position at the Department of Earth Sciences, University College London, U.K., where she is working on CryoSat-2.
Natalia Galin (M'02) received the B.Eng. degree in electrical engineering from the University of New South Wales, Sydney, Australia, in 2006 and has submitted her Ph.D. thesis “Snow Thickness Estimation Over Antarctic Sea Ice Using Helicopter Borne 2–8 GHZ FMCW Radar” to the University of Tasmania, Tasmania, Australia.
In 2009, she was a Visiting Postgraduate Fulbright Scholar at NASA/Goddard Space Flight Center, Greenbelt, MD. She now holds a research position at the Department of Earth Sciences, University College London, U.K., where she is working on CryoSat-2.View more
Center for Polar Observation and Modelling, Department of Earth Sciences, University College London, London, UK
Duncan J. Wingham received the B. Sc. degree in physics from the University of Leeds, Leeds, U.K., in 1979, and the Ph.D. degree in physics from the University of Bath, Bath, U.K., in 1984.
He joined the University College London (UCL) in 1986, where he held lecturing posts at the Mullard Space Science Laboratory and the Department of Electronic and Electrical Engineering. He was appointed to a Chair in the Department of Space and Climate Physics in, 1996, and was the Head of the Department of Earth Sciences at UCL, from 2005 to 2010. He is currently the Chairman of the Science Board of the U.K. Natural Environment Research Council, and, since 2000, the Lead Investigator of the ESA CryoSat and CryoSat-2 satellite missions.
Duncan J. Wingham received the B. Sc. degree in physics from the University of Leeds, Leeds, U.K., in 1979, and the Ph.D. degree in physics from the University of Bath, Bath, U.K., in 1984.
He joined the University College London (UCL) in 1986, where he held lecturing posts at the Mullard Space Science Laboratory and the Department of Electronic and Electrical Engineering. He was appointed to a Chair in the Department of Space and Climate Physics in, 1996, and was the Head of the Department of Earth Sciences at UCL, from 2005 to 2010. He is currently the Chairman of the Science Board of the U.K. Natural Environment Research Council, and, since 2000, the Lead Investigator of the ESA CryoSat and CryoSat-2 satellite missions.View more
VEGA Space GmbH, Hertfordshire, UK
Robert Cullen received the B. Sc. degree in electrical engineering from the University of Hull, Hull, U.K., the M.Sc. degree in satellite communications and spacecraft technology from the University College London (UCL), Surrey, U.K., and the Ph.D. degree in geophysics from the University of Aston, Birmingham, U.K.
He joined the Department of Space and Climate Physics at UCL, in 1998, where he worked on ESA EnviSAT and CryoSat mission simulation and ground processor algorithm development. In 2003, he joined Vega Space Ltd. and moved to ESA-ESTEC, Noordwijk, The Netherlands, as a Contractor to support CryoSat commissioning and validation preparation activities. After platform loss in October 2004, and following approval of the CryoSat-2 mission in 2006, he became the SIRAL-2 Instrument Procurement Manager and went on to perform key roles in CryoSat-2's launch preparation and execution, managing the mission's commissioning phase. Since June 2010, he has acted as a Payload Manager for the Jason-CS ocean surface topography series of satellites on behalf of a consortium including ESA, CNES, Eumetsat, and NOAA.
Robert Cullen received the B. Sc. degree in electrical engineering from the University of Hull, Hull, U.K., the M.Sc. degree in satellite communications and spacecraft technology from the University College London (UCL), Surrey, U.K., and the Ph.D. degree in geophysics from the University of Aston, Birmingham, U.K.
He joined the Department of Space and Climate Physics at UCL, in 1998, where he worked on ESA EnviSAT and CryoSat mission simulation and ground processor algorithm development. In 2003, he joined Vega Space Ltd. and moved to ESA-ESTEC, Noordwijk, The Netherlands, as a Contractor to support CryoSat commissioning and validation preparation activities. After platform loss in October 2004, and following approval of the CryoSat-2 mission in 2006, he became the SIRAL-2 Instrument Procurement Manager and went on to perform key roles in CryoSat-2's launch preparation and execution, managing the mission's commissioning phase. Since June 2010, he has acted as a Payload Manager for the Jason-CS ocean surface topography series of satellites on behalf of a consortium including ESA, CNES, Eumetsat, and NOAA.View more
New Tech Center, Reah System s, a., Louvain-la-Neuve, Belgium
Marco Fornari (M'09) received the M.Sc. degree in telecommunications engineering from the University of Rome “La Sapienza,” Rome, Italy, in 2006.
Following which, he joined ESA-ESTEC, Noordwijk, The Netherlands, as a Young Graduate Trainee, working on the CryoSat airborne campaigns. In 2007, he received a contract position at ESTEC, joining the CryoSat-2 project as the SIRAL Calibration Engineer. He is currently working at ESTEC, on the CryoSat-2 and Jason-CS projects.
Marco Fornari (M'09) received the M.Sc. degree in telecommunications engineering from the University of Rome “La Sapienza,” Rome, Italy, in 2006.
Following which, he joined ESA-ESTEC, Noordwijk, The Netherlands, as a Young Graduate Trainee, working on the CryoSat airborne campaigns. In 2007, he received a contract position at ESTEC, joining the CryoSat-2 project as the SIRAL Calibration Engineer. He is currently working at ESTEC, on the CryoSat-2 and Jason-CS projects.View more
National Oceanic and Atmospheric Administration, Silver Spring, MD, USA
Walter H. F. Smith received the B. Sc. degree in geological sciences from the University of Southern California, Los Angeles, in 1984, and the M.A. and Ph.D. degrees in marine geophysics from the Lamont Geological Observatory of Columbia University, Palisades, NY.
From 1990 to 1992, he was a Cecil and Ida Green Scholar in the Institute for Geophysics and Planetary Physics at the Scripps Institution of Oceanography, La Jolla, CA. Since 1992, he has been a Geophysicist in the Laboratory for Satellite Altimetry of the National Oceanic and Atmospheric Administration, Silver Spring, MD. In 2001, he led the 12-university, 4-federal-agency team that proposed “Altimetric BathymetrY from Surface Slopes (ABYSS),” a delay-Doppler synthetic radar aperture radar mission to map the oceans.
Walter H. F. Smith received the B. Sc. degree in geological sciences from the University of Southern California, Los Angeles, in 1984, and the M.A. and Ph.D. degrees in marine geophysics from the Lamont Geological Observatory of Columbia University, Palisades, NY.
From 1990 to 1992, he was a Cecil and Ida Green Scholar in the Institute for Geophysics and Planetary Physics at the Scripps Institution of Oceanography, La Jolla, CA. Since 1992, he has been a Geophysicist in the Laboratory for Satellite Altimetry of the National Oceanic and Atmospheric Administration, Silver Spring, MD. In 2001, he led the 12-university, 4-federal-agency team that proposed “Altimetric BathymetrY from Surface Slopes (ABYSS),” a delay-Doppler synthetic radar aperture radar mission to map the oceans.View more
Research Department, ECMWF, Reading, UK
Saleh Abdalla received the B. Sc. degree in civil engineering from Kuwait University, Kuwait City, Kuwait, in 1983, and the M.Sc. and Ph.D. degrees in coastal engineering from the Middle East Technical University, Ankara, Turkey, 1986 and 1991, respectively.
He continued to work as an Instructor and then as an Associate Professor. He joined the research Department of European Centre for Medium-Range Weather Forecasts, in 2000. He is working mainly on ocean wave modeling and data assimilation.
Saleh Abdalla received the B. Sc. degree in civil engineering from Kuwait University, Kuwait City, Kuwait, in 1983, and the M.Sc. and Ph.D. degrees in coastal engineering from the Middle East Technical University, Ankara, Turkey, 1986 and 1991, respectively.
He continued to work as an Instructor and then as an Associate Professor. He joined the research Department of European Centre for Medium-Range Weather Forecasts, in 2000. He is working mainly on ocean wave modeling and data assimilation.View more
