Generation of Nonlinear Internal Waves by the Transcritical Flow in the Kara Gates Strait
Abstract and keywords
Abstract:
In this study, we investigate the generation of nonlinear internal waves (NLIWs) by transcritical flow in the Kara Gates Strait. The analysis of the NLIW generation mechanisms is carried out on the basis of in-situ measurements obtained during «Floating University-2023» expedition in July 2023, and data of Arc2kmTM tidal model. The values of the linear phase velocity of the first mode internal waves in July 2023 ranged from 0.3 to 0.7 m/s. Based on these estimates and model fields of tidal current velocity, the Froude number values in the strait were calculated and its temporal variability was determined. During the tidal cycle, the area of the strait occupied by transcritical and supercritical (𝐹𝑟 > 1) flow regimes can increase substantially.. In a number of areas of the strait, conditions favorable for the generation of NLIWs are observed twice during the 𝑀2 tidal period or 4 times a day. Analysis of synchronous measurements from on board a drifting vessel showed that the flow regime during an 8-hour period successively changed from supercritical to transcritical and then to subcritical values. The total number of NLIW trains and pronounced solitary oscillations, as well as their height and steepness, increased significantly during the period of weakening tidal currents at subcritical values of the Froude number, qualitatively corresponding to the theory of the formation and propagation of NLIWs in the transcritical regime.

Keywords:
Nonlinear internal wave, internal wave generation mechanisms, transcritical regime, lee waves, Froude number, transformation of barotropic tidal energy, Kara Gates Strait, Arctic Ocean
Text
Text (PDF): Read Download
References

1. Lavrenov I. V. and Morozov E. G. Surface and internal waves in the Arctic seas. — St. Petersburg : Gidrometeoizdat, 2002. — 364 p. — (In Russian).

2. Svergun E. I., Zimin A. V., Atajanova O. A., et al. Variability of frontal zones and short-period internal waves in the Barents and Kara Seas from satellite observations during the warm period of 2007 // Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa. — 2018. — Vol. 15, no. 4. — P. 181–188. — https://doi.org/10.21046/2070-7401-2018-15-4-181-188. — (In Russian).

3. Svergun E. I., Konik A. A., Rodionov A. A., et al. Short-period variability of hydrophysical fields and processes in the Fourth Kuril Strait according to expedition studies // Podvodnye issledovaniia i robototehnika. — 2022. — Vol. 42, no. 4. — P. 53–61. — https://doi.org/10.37102/1992-4429_2022_42_04_05. — (In Russian).

4. Bukatov A. A., Solovei N. M. and Pavlenko E. A. Free Short-Period Internal Waves in the Arctic Seas of Russia // Physical Oceanography. — 2021. — Vol. 28, no. 6. — P. 599–611. — https://doi.org/10.22449/1573-160X-2021-6-599-611.

5. Clarke S. R. and Grimshaw R. H. J. Resonantly generated internal waves in a contraction // Journal of Fluid Mechanics. — 1994. — Vol. 274. — P. 139–161. — https://doi.org/10.1017/s0022112094002077.

6. Cushman-Roisin B. and Beckers J. M. Introduction to geophysical fluid dynamics physical and numerical aspects. — Academic Press, 2011. — 828 p.

7. da Silva J. C. B. and Helfrich K. R. Synthetic Aperture Radar observations of resonantly generated internal solitary waves at Race Point Channel (Cape Cod) // Journal of Geophysical Research: Oceans. — 2008. — Vol. 113, no. C11. — https://doi.org/10.1029/2008jc005004.

8. Gerkema T. and Zimmerman J. T. F. An introduction to internal waves. — Texel : Royal NIOZ, 2008. — 207 p.

9. Greene C. A., Erofeeva S., Padman L., et al. Tide Model Driver for MATLAB // Journal of Open Source Software. — 2024. — Vol. 9, no. 95. — P. 6018. — https://doi.org/10.21105/joss.06018.

10. Grimshaw R. H. J. and Smyth N. Resonant flow of a stratified fluid over topography // Journal of Fluid Mechanics. — 1986. — Vol. 169. — P. 429–464. — https://doi.org/10.1017/s002211208600071x.

11. Jackson C. R., Silva J. C. B. Da and Jeans G. The Generation of Nonlinear Internal Waves // Oceanography. — 2012. — Vol. 25, no. 2. — P. 108–123. — https://doi.org/10.5670/oceanog.2012.46.

12. Kopyshov I. O., Kozlov I. E., Shiryborova A. I., et al. Properties of Short-Period Internal Waves in the Kara Gates Strait Revealed from Spaceborne SAR Data // Russian Journal of Earth Sciences. — 2023. — Vol. 23, no. 5. — ES0210. — https://doi.org/10.2205/2023es02si10.

13. Kozlov I., Kudryavtsev V., Zubkova E. V., et al. Characteristics of short-period internal waves in the Kara Sea inferred from satellite SAR data // Izvestiya, Atmospheric and Oceanic Physics. — 2015. — Vol. 51, no. 9. — P. 1073–1087. — https://doi.org/10.1134/s0001433815090121.

14. Kozlov I. E., Kopyshov I. O., Frey D. I., et al. Multi-Sensor Observations Reveal Large-Amplitude Nonlinear Internal Waves in the Kara Gates, Arctic Ocean // Remote Sensing. — 2023. — Vol. 15, no. 24. — P. 5769. — https://doi.org/10.3390/rs15245769.

15. Li Q., Wu H., Yang H., et al. A numerical simulation of the generation and evolution of nonlinear internal waves across the Kara Strait // Acta Oceanologica Sinica. — 2019. — Vol. 38, no. 5. — P. 1–9. — https://doi.org/10.1007/s13131-019-1437-z.

16. Maxworthy T. A note on the internal solitary waves produced by tidal flow over a three-dimensional ridge // Journal of Geophysical Research: Oceans. — 1979. — Vol. 84, no. C1. — P. 338–346. — https://doi.org/10.1029/JC084iC01p00338.

17. Melville W. K. and Helfrich K. R. Transcritical two-layer flow over topography // Journal of Fluid Mechanics. — 1987. — Vol. 178. — P. 31–52. — https://doi.org/10.1017/s0022112087001101.

18. Morozov E. G. Oceanic Internal Tides: Observations, Analysis and Modeling. — Switzerland : Springer International Publishing, 2018. — https://doi.org/10.1007/978-3-319-73159-9.

19. Morozov E. G., Kozlov I. E., Shchuka S. A., et al. Internal tide in the Kara Gates Strait // Oceanology. — 2017. — Vol. 57, no. 1. — P. 8–18. — https://doi.org/10.1134/s0001437017010106.

20. Morozov E. G., Parrilla-Barrera G., Velarde M. G., et al. The straits of Gibraltar and Kara Gates: a comparison of internal tides // Oceanologica Acta. — 2003. — Vol. 26, no. 3. — P. 231–241. — https://doi.org/10.1016/s0399-1784(03)00023-9.

21. Rippeth T. P., Vlasenko V., Stashchuk N., et al. Tidal Conversion and Mixing Poleward of the Critical Latitude (an Arctic Case Study) // Geophysical Research Letters. — 2017. — Vol. 44, no. 24. — P. 12349–12357. — https://doi.org/10.1002/2017gl075310.

22. Vlasenko V., Stashchuk N., Hutter K., et al. Nonlinear internal waves forced by tides near the critical latitude // Deep Sea Research Part I: Oceanographic Research Papers. — 2003. — Vol. 50, no. 3. — P. 317–338. — https://doi.org/10.1016/s0967-0637(03)00018-9.

23. Zimin A., Kozlov I. and Kopyshov I. Temperature, Salinity, Depth data in the Kara Gates Strait in July 2023, Arctic Ocean. — Version 1. — 2026. — https://doi.org/10.17632/tr8fywy68r. — In press.


Login or Create
* Forgot password?