Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2023, Vol. 20, No. 4, pp. 20-29
On the accuracy of removing the tidal component from IMMOAD SSHA satellite altimetry data
G.V. Shevchenko
1, 2 , A.A. Romanov
3 , A.T. Tsoi
1 1 Russian Federal Research Institute of Fisheries and Oceanography, Sakhalin Branch, Yuzhno-Sakhalinsk, Russia
2 Institute of Marine Geology and Geophysics FEB RAS, Yuzhno-Sakhalinsk, Russia
3 AO Central Research Institute for Machine Building, Korolev, Moscow Region, Russia
Accepted: 11.08.2023
DOI: 10.21046/2070-7401-2023-20-4-20-29
An array of level surface anomalies formed according to data from four artificial Earth satellites (IMMOAD SSHA) for 1992‒2022 was tested for tidal component elimination quality. The testing procedure was carried out by direct calculation of the amplitudes and phases of 8 main tidal waves (4 diurnal and 4 semidiurnal ranges) at each point of the subsatellite tracks. It was revealed that in a number of areas (primarily in the coastal waters of the Sea of Okhotsk and in the zone of influence of the warm Kuroshio Current), the amplitudes of several waves have a value of several centimeters, which confirms the insufficient accuracy of eliminating tides in the tested massif. The average values of the tidal series are also not small, and differ in different parts of the studied water area. This indicates that the tide, which has not been sufficiently eliminated, introduces false constant currents into the massif, the most significant in the area of influence of the warm Kuroshio Current. At some points in the region, due to the specific discreteness of satellite altimetry series, the residual tides create false annual and semi-annual variations, which can distort the pattern of seasonal fluctuations when using the array to study them.
Keywords: satellite altimetry, sea level, anomaly, tide, amplitude, phase, northwestern part of the Pacific Ocean, Far Eastern seas
Full textReferences:
- Shevchenko G. V., Romanov A. A., Tides characteristics in the Sea of Okhotsk definition from Topex/Poseidon sea level data, Earth Research from the Space, 2004, No. 1, pp. 49–62 (in Russian).
- Beckley B. D., Callahan P. S., Hancock D. W. et al., On the “cal-mode” correction to Topex satellite altimetry and its effect on the global mean sea level time series, J. Geophysical Research: Oceans, 2017, Vol. 122, pp. 8371‒8384, https://doi.org/10.1002/2017JC013090.
- Beckley B., Zelensky N. P., Holmes S. A. et al., Integrated Multi-Mission Ocean Altimeter Data for Climate Research complete time series Version 5.0, 2021, PO.DAAC, CA, USA, https:://doi.org/10.5067/ALTTS-TJA50.
- Benada J. R., Merged GDR (Topex/Poseidon), Generation B Users Handbook, Version 2.0, Physical Oceanography Distributed Active Archive Center (PODAAC), Jet Propulsion Laboratory, Pasadena: JPL, 1997, 131 p.
- Cartwright D. E., Edden A. C., Corrected tables of tidal harmonics, Geophysical J. Intern., 1973, Vol. 33, pp. 253–264.
- Choi B. H., Kim D. H., Fang Y., Tides in the East Asian seas from a fine-resolution global ocean tide model, Marine Technology Society J., 1999, Vol. 33, Issue 1, pp. 36-44.
- Ray R. D., Erofeeva S. Y., Long-period tidal variations in the length of day, J. Geophysical Research: Solid Earth, 2014, Vol. 119, pp. 1498–1509, DOI: 10.1002/2013JB010830.
- Zaron E. D., Baroclinic tidal sea level from exact-repeat mission altimetry, J. Physical Oceanography, 2019, Vol. 49, Issue 1, pp. 193–210, DOI: 10.1175/JPO-D-18-0127.1.