• Archer, M. R., Z. Li, J. Wang, and L.-L. Fu, 2022: Reconstructing fine-scale ocean variability via data assimilation of the SWOT pre-launch in situ observing system. J. Geophys. Res. Oceans, 127, e2021JC017362, https://doi.org/10.1029/2021JC017362.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bertiger, W., and Coauthors, 2010: Single receiver phase ambiguity resolution with GPS data. J. Geod., 84, 327337, https://doi.org/10.1007/s00190-010-0371-9.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bertiger, W., and Coauthors, 2020: GipsyX/RTGx: A new tool set for space geodetic operations and research. Adv. Space Res., 66, 469489, https://doi.org/10.1016/j.asr.2020.04.015.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bonnefond, P., and Coauthors, 2019: Corsica: A 20-yr multi-mission absolute altimeter calibration site. Adv. Space Res., 68, 11711186, https://doi.org/10.1016/j.asr.2019.09.049.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Callies, J., and W. Wu, 2019: Some expectations for submesoscale sea surface height variance spectra. J. Phys. Oceanogr., 49, 22712289, https://doi.org/10.1175/JPO-D-18-0272.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Capet, X., J. C. McWilliams, M. J. Molemaker, and A. F. Shchepetkin, 2008a: Mesoscale to submesoscale transition in the California Current system. Part I: Flow structure, eddy flux, and observational tests. J. Phys. Oceanogr., 38, 2943, https://doi.org/10.1175/2007JPO3671.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Capet, X., J. C. McWilliams, M. J. Molemaker, and A. F. Shchepetkin, 2008b: Mesoscale to submesoscale transition in the California Current system. Part III: Energy balance and flux. J. Phys. Oceanogr., 38, 22562269, https://doi.org/10.1175/2008JPO3810.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chereskin, T. K., C. B. Rocha, S. T. Gille, D. Menemenlis, and M. Passaro, 2019: Characterizing the transition from balanced to unbalanced motions in the Southern California Current. J. Geophys. Res. Oceans, 124, 20882109, https://doi.org/10.1029/2018JC014583.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Clark, E. B., and Coauthors, 2018: Station-keeping underwater gliders using a predictive ocean circulation model and applications to SWOT calibration and validation. IEEE J. Oceanic Eng., 45, 371384, https://doi.org/10.1109/JOE.2018.2886092.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Collins, C. A., T. Margolina, T. A. Rago, and L. Ivanov, 2013: Looping RAFOS floats in the California Current system. Deep Sea Res. II, 85, 4261, https://doi.org/10.1016/j.dsr2.2012.07.027.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Copernicus Climate Change Service, 2017: ERA5: Fifth generation of ECMWF atmospheric reanalyses of the global climate. Copernicus Climate Change Service Climate Data Store, accessed 1 March 2020, https://cds.climate.copernicus.eu/cdsapp\#!/home.

    • Search Google Scholar
    • Export Citation
  • D’Addezio, J. M., S. Smith, G. A. Jacobs, R. Helber, C. Rowley, I. Souopgui, and M. J. Carrier, 2019: Quantifying wavelengths constrained by simulated SWOT observations in a submesoscale resolving ocean analysis/forecasting system. Ocean Modell., 135, 4055, https://doi.org/10.1016/j.ocemod.2019.02.001.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Desai, S., and Coauthors, 2018: Surface Water and Ocean Topography Mission (SWOT) project science requirements document. Jet Propulsion Laboratory Doc. JPL D-61923, revision B, 29 pp.

    • Search Google Scholar
    • Export Citation
  • d’Ovidio, F., and Coauthors, 2019: Frontiers in fine-scale in situ studies: Opportunities during the SWOT fast sampling phase. Front. Mar. Sci., 6, 168, https://doi.org/10.3389/fmars.2019.00168.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Dufau, C., M. Orsztynowicz, G. Dibarboure, R. Morrow, and P. Traon, 2016: Mesoscale resolution capability of altimetry: Present and future. J. Geophys. Res. Oceans, 121, 49104927, https://doi.org/10.1002/2015JC010904.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Durand, M., L.-L. Fu, D. P. Lettenmaier, D. E. Alsdorf, E. Rodriguez, and D. Esteban-Fernandez, 2010: The Surface Water and Ocean Topography mission: Observing terrestrial surface water and oceanic submesoscale eddies. Proc. IEEE, 98, 766779, https://doi.org/10.1109/JPROC.2010.2043031.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Eble, M. C., and F. I. Gonzalez, 1991: Deep-ocean bottom pressure measurements in the northeast Pacific. J. Atmos. Oceanic Technol., 8, 221233, https://doi.org/10.1175/1520-0426(1991)008<0221:DOBPMI>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Flament, P., L. Armi, and L. Washburn, 1985: The evolving structure of an upwelling filament. J. Geophys. Res., 90, 11 76511 778, https://doi.org/10.1029/JC090iC06p11765.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Fu, L.-L., and A. Cazenave, 2001: Satellite Altimetry and Earth Sciences. Academic Press, 509 pp.

  • Fu, L.-L., and C. Ubelmann, 2014: On the transition from profile altimeter to swath altimeter for observing global ocean surface topography. J. Atmos. Oceanic Technol., 31, 560568, https://doi.org/10.1175/JTECH-D-13-00109.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gula, J., T. M. Blacic, and R. E. Todd, 2019: Submesoscale coherent vortices in the Gulf Stream. Geophys. Res. Lett., 46, 27042714, https://doi.org/10.1029/2019GL081919.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Guthrie, J., and Coauthors, 2020: Preliminary results from the first deployments of the dynamic ocean topography buoy: In-situ observations of sea surface height in ice-covered seas. AGU Ocean Sciences Meeting, San Francisco, CA, Amer. Geophys. Union, Abstract HE14B-1930, https://agu.confex.com/agu/osm20/meetingapp.cgi/Paper/648899.

    • Search Google Scholar
    • Export Citation
  • Haines, B., S. Desai, C. Meinig, and S. Stalin, 2017: CAL/VAL of the SWOT SSH spectrum: Moored GPS approach. SWOT Science Team Meeting, Toulouse, France, NASA, https://trs.jpl.nasa.gov/handle/2014/48164.

    • Search Google Scholar
    • Export Citation
  • Haines, B., S. Desai, A. Dodge, R. Leben, M. Shannon, C. Meinig, and S. Stalin, 2019: The Harvest experiment: New results from the platform and moored GPS buoys. Ocean Surface Topography Science Team Meeting, Chicago, IL, NASA.

    • Search Google Scholar
    • Export Citation
  • Haines, B., S. Desai, D. Kubitschek, and R. Leben, 2021: A brief history of the Harvest experiment: 1989–2019. Adv. Space Res., 68, 11611170, https://doi.org/10.1016/j.asr.2020.08.013.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hersbach, H., and Coauthors, 2020: The ERA5 global reanalysis. Quart. J. Roy. Meteor. Soc., 146, 19992049, https://doi.org/10.1002/qj.3803.

  • Hickey, B. M., 1979: The California Current system—Hypotheses and facts. Prog. Oceanogr., 8, 191279, https://doi.org/10.1016/0079-6611(79)90002-8.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ikeda, M., and W. J. Emery, 1984: Satellite observations and modeling of meanders in the California Current system off Oregon and Northern California. J. Phys. Oceanogr., 14, 14341450, https://doi.org/10.1175/1520-0485(1984)014<1434:SOAMOM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kanzow, T., U. Send, W. Zenk, A. D. Chave, and M. Rhein, 2006: Monitoring the integrated deep meridional flow in the tropical North Atlantic: Long-term performance of a geostrophic array. Deep-Sea Res. I, 53, 528546, https://doi.org/10.1016/j.dsr.2005.12.007.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • LaCasce, J. H., and A. Mahadevan, 2006: Estimating subsurface horizontal and vertical velocities from sea surface temperature. J. Mar. Res., 64, 695721, https://doi.org/10.1357/002224006779367267.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lapeyre, G., and P. Klein, 2006: Dynamics of the upper oceanic layers in terms of surface quasigeostrophy theory. J. Phys. Oceanogr., 36, 165176, https://doi.org/10.1175/JPO2840.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, Z., J. Wang, and L.-L. Fu, 2019: An observing system simulation experiment for ocean state estimation to assess the performance of the SWOT mission: Part 1—A twin experiment. J. Geophys. Res. Oceans, 124, 48384855, https://doi.org/10.1029/2018JC014869.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Meinig, C., S. E. Stalin, A. I. Nakamura, and H. B. Milburn, 2005: Real‐time deep‐ocean tsunami measuring, monitoring, and reporting system: The NOAA DART II description and disclosure. NOAA NDBC Rep., 15 pp.

    • Search Google Scholar
    • Export Citation
  • Melville, W. K., L. Lenain, D. R. Cayan, M. Kahru, J. P. Kleissl, P. Linden, and N. M. Statom, 2016: The Modular Aerial Sensing System. J. Atmos. Oceanic Technol., 33, 11691184, https://doi.org/10.1175/JTECH-D-15-0067.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mihaly, S. F., R. E. Thomson, and A. B. Rabinovich, 1998: Evidence for nonlinear interaction between internal waves of inertial and semidiurnal frequency. Geophys. Res. Lett., 25, 12051208, https://doi.org/10.1029/98GL00722.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Morrow, R., and Coauthors, 2019: Global observations of fine-scale ocean surface topography with the Surface Water and Ocean Topography (SWOT) mission. Front. Mar. Sci., 6, 232, https://doi.org/10.3389/fmars.2019.00232.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Osse, T. J., C. Meinig, S. Stalin, and H. Milburn, 2015: The Prawler, a vertical profiler powered by wave energy. OCEANS 2015, Washington, DC, IEEE, https://doi.org/10.23919/OCEANS.2015.7404354.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pinkel, R., M. A. Goldin, J. A. Smith, O. M. Sun, A. A. Aja, M. N. Bui, and T. Hughen, 2011: The Wirewalker: A vertically profiling instrument carrier powered by ocean waves. J. Atmos. Oceanic Technol., 28, 426435, https://doi.org/10.1175/2010JTECHO805.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ponte, A. L., and P. Klein, 2015: Incoherent signature of internal tides on sea level in idealized numerical simulations. Geophys. Res. Lett., 42, 15201526, https://doi.org/10.1002/2014GL062583.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Pujol, M. I., Y. Faugère, G. Taburet, S. Dupuy, C. Pelloquin, M. Ablain, and N. Picot, 2016: DUACS DT2014: The new multi‐mission altimeter data set reprocessed over 20 years. Ocean Sci., 12, 10671090, https://doi.org/10.5194/os-12-1067-2016.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qiu, B., S. Chen, P. Klein, J. Wang, H. Torres, L. Fu, and D. Menemenlis, 2018: Seasonality in transition scale from balanced to unbalanced motions in the World Ocean. J. Phys. Oceanogr., 48, 591605, https://doi.org/10.1175/JPO-D-17-0169.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Quartly, G. D., G. Chen, F. Nencioli, R. Morrow, and N. Picot, 2021: An overview of requirements, procedures and current advances in the calibration/validation of radar altimeters. Remote Sens., 13, 125, https://doi.org/10.3390/rs13010125.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ray, R. D., 2013: Precise comparisons of bottom-pressure and altimetric ocean tides. J. Geophys. Res. Oceans, 118, 45704584, https://doi.org/10.1002/jgrc.20336.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Rocha, C., T. Chereskin, G. Gille, and D. Menemenlis, 2016: Mesoscale to submesoscale wavenumber spectra in Drake Passage. J. Phys. Oceanogr., 46, 601620, https://doi.org/10.1175/JPO-D-15-0087.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Rudnick, D. L., K. D. Zaba, R. E. Todd, and R. E. Davis, 2017: A climatology of the California Current system from a network of underwater gliders. Prog. Oceanogr., 154, 64106, https://doi.org/10.1016/j.pocean.2017.03.002.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Savage, A. C., and Coauthors, 2017: Spectral decomposition of internal gravity wave sea surface height in global models. J. Geophys. Res. Oceans, 122, 78037821, https://doi.org/10.1002/2017JC013009.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schaeffer, P., and Coauthors, 2018: What do we need to improve the next mean sea surface? Ocean Surface Topography Science Team Meeting, Ponta Delgado, Portugal, NASA.

    • Search Google Scholar
    • Export Citation
  • Strub, P. T., and C. James, 2000: Altimeter-derived variability of surface velocities in the California Current system: 2. Seasonal circulation and eddy statistics. Deep-Sea Res. II, 47, 831870, https://doi.org/10.1016/S0967-0645(99)00129-0.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Su, Z., and Coauthors, 2018: Ocean submesoscales as a key component of the global heat budget. Nat. Commun., 9, 775, https://doi.org/10.1038/s41467-018-02983-w.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Taburet, G., A. Sanchez‐Roman, M. Ballarotta, M. I. Pujol, J. F. Legeais, F. Fournier, Y. Faugere, and G. Dibarboure, 2019: DUACS DT‐2018: 25 years of reprocessed sea level altimeter products. Ocean Sci., 15, 12071224, https://doi.org/10.5194/os-15-1207-2019.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Torres, H. S., P. Klein, D. Menemenlis, B. Qiu, Z. Su, J. Wang, S. Chen, and L. Fu, 2018: Partitioning ocean motions into balanced motions and internal gravity waves: A modeling study in anticipation of future space missions. J. Geophys. Res. Oceans, 123, 80848105, https://doi.org/10.1029/2018JC014438.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, J., and L.-L. Fu, 2019: On the long-wavelength validation of the SWOT KaRIn measurement. J. Atmos. Oceanic Technol., 36, 843848, https://doi.org/10.1175/JTECH-D-18-0148.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, J., L.-L. Fu, B. Qiu, D. Menemenlis, J. T. Farrar, Y. Chao, A. F. Thompson, and M. M. Flexas, 2018: An observing system simulation experiment for the calibration and validation of the Surface Water Ocean Topography sea surface height measurement using in situ platforms. J. Atmos. Oceanic Technol., 35, 281297, https://doi.org/10.1175/JTECH-D-17-0076.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, J., L.-L. Fu, H. S. Torres, S. Chen, B. Qiu, and D. Menemenlis, 2019: On the spatial scales to be resolved by the Surface Water and Ocean Topography Ka-band radar interferometer. J. Atmos. Oceanic Technol., 36, 8799, https://doi.org/10.1175/JTECH-D-18-0119.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Watts, D., and H. T. Rossby, 1977: Measuring dynamic heights with inverted echo sounders: Results from MODE. J. Phys. Oceanogr., 7, 345358, https://doi.org/10.1175/1520-0485(1977)007<0345:MDHWIE>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wunsch, C., and D. Stammer, 1997: Atmospheric loading and the oceanic inverted barometer effect. Rev. Geophys., 35, 79107, https://doi.org/10.1029/96RG03037.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yu, X., A. L. Ponte, S. Elipot, D. Menemenlis, E. D. Zaron, and R. Abernathey, 2019: Surface kinetic energy distributions in the global oceans from a high‐resolution numerical model and surface drifter observations. Geophys. Res. Lett., 46, 97579766, https://doi.org/10.1029/2019GL083074.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zaron, E. D., 2019: Baroclinic tidal sea level from exact-repeat mission altimetry. J. Phys. Oceanogr., 49, 193210, https://doi.org/10.1175/JPO-D-18-0127.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhao, Z., and Coauthors, 2019: Decomposition of the multimodal multidirectional M2 internal tide field. J. Atmos. Oceanic Technol., 36, 11571173, https://doi.org/10.1175/JTECH-D-19-0022.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhou, B., C. Watson, B. Legresy, M. King, J. Beardsley, and A. Deane, 2020: GNSS/INS-equipped buoys for altimetry validation: Lessons learnt and new directions from the Bass Strait validation facility. Remote Sens., 12, 3001, https://doi.org/10.3390/rs12183001.

    • Crossref
    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 534 528 96
Full Text Views 239 238 48
PDF Downloads 253 251 63

On the Development of SWOT In Situ Calibration/Validation for Short-Wavelength Ocean Topography

View More View Less
  • 1 aJet Propulsion Laboratory, California Institute of Technology, Pasadena, California
  • | 2 bScripps Institution of Oceanography, University of California, San Diego, La Jolla, California
  • | 3 cDepartment of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, California
  • | 4 dWoods Hole Oceanographic Institution, Woods Hole, Massachusetts
  • | 5 ePacific Marine Environmental Laboratory, National Oceanic and Atmospheric Administration, Seattle, Washington
  • | 6 fRutgers, The State University of New Jersey, New Brunswick, New Jersey
  • | 7 gRemote Sensing Solutions, Monrovia, California
  • | 8 hNASA Goddard Space Flight Center, Greenbelt, Maryland
Restricted access

Abstract

The future Surface Water and Ocean Topography (SWOT) mission aims to map sea surface height (SSH) in wide swaths with an unprecedented spatial resolution and subcentimeter accuracy. The instrument performance needs to be verified using independent measurements in a process known as calibration and validation (Cal/Val). The SWOT Cal/Val needs in situ measurements that can make synoptic observations of SSH field over an O(100) km distance with an accuracy matching the SWOT requirements specified in terms of the along-track wavenumber spectrum of SSH error. No existing in situ observing system has been demonstrated to meet this challenge. A field campaign was conducted during September 2019–January 2020 to assess the potential of various instruments and platforms to meet the SWOT Cal/Val requirement. These instruments include two GPS buoys, two bottom pressure recorders (BPR), three moorings with fixed conductivity–temperature–depth (CTD) and CTD profilers, and a glider. The observations demonstrated that 1) the SSH (hydrostatic) equation can be closed with 1–3 cm RMS residual using BPR, CTD mooring and GPS SSH, and 2) using the upper-ocean steric height derived from CTD moorings enable subcentimeter accuracy in the California Current region during the 2019/20 winter. Given that the three moorings are separated at 10–20–30 km distance, the observations provide valuable information about the small-scale SSH variability associated with the ocean circulation at frequencies ranging from hourly to monthly in the region. The combined analysis sheds light on the design of the SWOT mission postlaunch Cal/Val field campaign.

© 2022 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Jinbo Wang, jinbo.wang@jpl.nasa.gov

Abstract

The future Surface Water and Ocean Topography (SWOT) mission aims to map sea surface height (SSH) in wide swaths with an unprecedented spatial resolution and subcentimeter accuracy. The instrument performance needs to be verified using independent measurements in a process known as calibration and validation (Cal/Val). The SWOT Cal/Val needs in situ measurements that can make synoptic observations of SSH field over an O(100) km distance with an accuracy matching the SWOT requirements specified in terms of the along-track wavenumber spectrum of SSH error. No existing in situ observing system has been demonstrated to meet this challenge. A field campaign was conducted during September 2019–January 2020 to assess the potential of various instruments and platforms to meet the SWOT Cal/Val requirement. These instruments include two GPS buoys, two bottom pressure recorders (BPR), three moorings with fixed conductivity–temperature–depth (CTD) and CTD profilers, and a glider. The observations demonstrated that 1) the SSH (hydrostatic) equation can be closed with 1–3 cm RMS residual using BPR, CTD mooring and GPS SSH, and 2) using the upper-ocean steric height derived from CTD moorings enable subcentimeter accuracy in the California Current region during the 2019/20 winter. Given that the three moorings are separated at 10–20–30 km distance, the observations provide valuable information about the small-scale SSH variability associated with the ocean circulation at frequencies ranging from hourly to monthly in the region. The combined analysis sheds light on the design of the SWOT mission postlaunch Cal/Val field campaign.

© 2022 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Jinbo Wang, jinbo.wang@jpl.nasa.gov
Save