FN Archimer Export Format PT J TI Obukhov Length Estimation From Spaceborne Radars BT AF O’Driscoll, Owen Mouche, Alexis Chapron, Bertrand Kleinherenbrink, Marcel López‐Dekker, Paco AS 1:1;2:1;3:1;4:2;5:2; FF 1:;2:PDG-ODE-LOPS-SIAM;3:PDG-ODE-LOPS-SIAM;4:;5:; C1 University Brest CNRS Ifremer IRD Laboratoire d’Océanographie Physique et Spatiale (LOPS) IUEM Plouzané, France Geoscience and Remote Sensing Civil Engineering and Geosciences Delft University of Technology Delft ,The Netherlands C2 IFREMER, FRANCE UNIV DELFT, NETHERLANDS SI BREST SE PDG-ODE-LOPS-SIAM UM LOPS IF 5.2 TC 0 UR https://archimer.ifremer.fr/doc/00850/96224/104384.pdf https://archimer.ifremer.fr/doc/00850/96224/104385.pdf LA English DT Article DE ;Obukhov length;surface-layer stability;SAR;machine learning;regression AB Two air‐sea interaction quantification methods are employed on synthetic aperture radar (SAR) scenes containing atmospheric‐turbulence signatures. Quantification performance is assessed on Obukhov length L, an atmospheric surface‐layer stability metric. The first method correlates spectral energy at specific turbulence‐spectrum wavelengths directly to L. Improved results are obtained from the second method, which relies on a machine‐learning algorithm trained on a wider array of SAR‐derived parameters. When applied on scenes containing convective signatures, the second method is able to predict approximately 80% of observed variance with respect to validation. Estimated wind speed provides the bulk of predictive power while parameters related to the kilometer‐scale distribution of spectral energy contribute to a significant reduction in prediction errors, enabling the methodology to be applied on a scene‐by‐scene basis. Differences between these physically based estimates and parameterized numerical models may guide the latter's improvement. PY 2023 PD AUG SO Geophysical Research Letters SN 0094-8276 PU American Geophysical Union (AGU) VL 50 IS 15 DI 10.1029/2023GL104228 ID 96224 ER EF