Assessing the capability of three different altimetry satellite missions to observe the Northern Current by using a high-resolution model

Abstract - 1 ∘  E is 6.9 cm, extending over 20 km. These variations show a clear seasonal pattern, but high-frequency signals are also present most of the time. In comparison, in 1 Hz altimetry data, the mean sea level drop associated with the Northern Current is overestimated by 3.0 cm for Jason-2, but this overestimation is significantly less with SARAL/AltiKa and Sentinel-3A (0.3 and 1.4 cm respectively). In terms of corresponding sea level variability, Jason-2 and SARAL altimetry estimates are larger than the model reference (+ 1.3 and + 1  cm respectively), whereas Sentinel-3A shows closer values (- 0.4  cm). When we derive geostrophic surface currents from the satellite sea level variations without any data filtering, in comparison to the model, the standard deviations of the velocity values are also very different from one mission to the other (3.7 times too large for Jason-2 but 2.4 and 2.9 times too large for SARAL and Sentinel-3A respectively). When low-pass filtering altimetry sea level data with different cutoff wavelengths, the best agreement between the model and the altimetry distributions of velocity values are obtained with a 60, 30 and 40–50 km cutoff wavelength for Jason-2, SARAL and Sentinel-3A data respectively. This study shows that using a high-resolution model as a reference for altimetry data allows us not only to illustrate how the advances in the performances of altimeters and in the data processing improve the observation of coastal currents but also to quantify the corresponding gain.

Angaben zum Objekt

• Standort: Deutsche Nationalbibliothek Frankfurt am Main
• Umfang: Online-Ressource
• Sprache: Englisch

Verweise und Beziehungen

• Erschienen in: Assessing the capability of three different altimetry satellite missions to observe the Northern Current by using a high-resolution model ; volume:19 ; number:3 ; year:2023 ; pages:903-921 ; extent:19 ; Ocean science ; 19, Heft 3 (2023), 903-921 (gesamt 19)

Beteiligte, Orts- und Zeitangaben

• Urheber: Carret, Alice ; Birol, Florence ; Estournel, Claude ; Zakardjian, Bruno

Weitere Informationen

• DOI: 10.5194/os-19-903-2023
• URN: urn:nbn:de:101:1-2023062904452616523407
• Rechteinformation: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Letzte Aktualisierung: 07.03.0010, 11:58 MEZ