Articles | Volume 30, issue 4
https://doi.org/10.5194/npg-30-515-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/npg-30-515-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
21 Nov 2023
Research article |
| 21 Nov 2023
| 21 Nov 2023
Superstatistical analysis of sea surface currents in the Gulf of Trieste, measured by high-frequency radar, and its relation to wind regimes using the maximum-entropy principle
Sofia Flora
CORRESPONDING AUTHOR
Dipartimento di Matematica e Geoscienze, University of Trieste, Trieste, Italy
National Institute of Oceanography and Applied Geophysics – OGS, Oceanographic Section, Trieste, Italy
Laura Ursella
National Institute of Oceanography and Applied Geophysics – OGS, Oceanographic Section, Trieste, Italy
Achim Wirth
Univ. Grenoble Alpes, CNRS, Grenoble INP, LEGI, 38000 Grenoble, France
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Cited articles
Bogunović, B. and Malačič, V.: Circulation in the Gulf of Trieste: Measurements and model results, Nuovo Cimento C, 31, 301–326, 2008. a
CRMA – Centro Regionale di Modellistica Ambientale: Progetto NAUSICA – Downscaling di analisi meteorologiche ad alta risoluzione sul dominio Alpe Adria, https://www.arpa.fvg.it, last access: 29 March 2023. a
Corgnati, L., Mantovani, C., Novellino, A., Rubio, A., and Mader, J.: Recommendation Report 2 on improved common procedures for HFR QC analysis, JERICO-NEXT WP5-Data Management, Deliverable 5.14, Version 1.0., FREMER, https://doi.org/10.25607/OBP-944, 2018. a
Costa, M. O., Silva, R., and Anselmo, D. H. A. L.: Superstatistical and DNA sequence coding of the human genome, Phys. Rev. E, 106, 064407, https://doi.org/10.1103/PhysRevE.106.064407, 2022. a
Crombie, D. D.: Doppler spectrum of sea echo at 13.56 Mc./s., Nature, 175, 681–682, 1955. a
dos Santos, M., Menon, L., and Cius, D.: Superstatistical approach of the anomalous exponent for scaled Brownian motion, Chaos Soliton. Fract., 164, 112740, https://doi.org/10.1016/j.chaos.2022.112740, 2022. a
Ghil, M., Yiou, P., Hallegatte, S., Malamud, B. D., Naveau, P., Soloviev, A., Friederichs, P., Keilis-Borok, V., Kondrashov, D., Kossobokov, V., Mestre, O., Nicolis, C., Rust, H. W., Shebalin, P., Vrac, M., Witt, A., and Zaliapin, I.: Extreme events: dynamics, statistics and prediction, Nonlin. Processes Geophys., 18, 295–350, https://doi.org/10.5194/npg-18-295-2011, 2011. a, b
Goglio, A. C.: Progetto NAUSICA – Downscaling di analisi meteorologiche ad alta risoluzione sul dominio Alpe Adria, ARPA FVG, https://www.arpa.fvg.it/export/sites/default/tema/crma/pubblicazioni/docs_pubblicazioni/2018gen01_arpafvg_crma_nausica_rap2018_001.pdf (last access: 29 March 2023), 2018. a
Jeffries, M. A. and Lee, C. M.: A climatology of the northern Adriatic Sea's response to bora and river forcing, J. Geophys. Res.-Oceans, 112, C03S02, https://doi.org/10.1029/2006JC003664, 2007. a, b
Lorente, P., Aguiar, E., Bendoni, M., Berta, M., Brandini, C., Cáceres-Euse, A., Capodici, F., Cianelli, D., Ciraolo, G., Corgnati, L., Dadić, V., Doronzo, B., Drago, A., Dumas, D., Falco, P., Fattorini, M., Gauci, A., Gómez, R., Griffa, A., Guérin, C.-A., Hernández-Carrasco, I., Hernández-Lasheras, J., Ličer, M., Magaldi, M. G., Mantovani, C., Mihanović, H., Molcard, A., Mourre, B., Orfila, A., Révelard, A., Reyes, E., Sánchez, J., Saviano, S., Sciascia, R., Taddei, S., Tintoré, J., Toledo, Y., Ursella, L., Uttieri, M., Vilibić, I., Zambianchi, E., and Cardin, V.: Coastal high-frequency radars in the Mediterranean – Part 1: Status of operations and a framework for future development, Ocean Sci., 18, 761–795, https://doi.org/10.5194/os-18-761-2022, 2022. a
Malačič, V., Petelin, B., Gačić, M., Artegiani, A., and Orlić, M.: Regional Studies, Springer Netherlands, Dordrecht, https://doi.org/10.1007/978-94-015-9819-4_6, pp. 167–216, 2001. a, b
Okorie, U. S., Ikot, A. N., Okon, I. B., Obagboye, L. F., Horchani, R., Abdullah, H. Y., Qadir, K. W., and Abdel-Aty, A.-H.: Exact solutions of κ-dependent Schrödinger equation with quantum pseudo-harmonic oscillator and its applications for the thermodynamic properties in normal and superstatistics, Sci. Rep.-UK, 13, 2108, https://doi.org/10.1038/s41598-023-28973-7, 2023. a
Poulain, P.-M. and Raicich, F.: Forcings, Springer Netherlands, Dordrecht, https://doi.org/10.1007/978-94-015-9819-4_2, pp. 45–65, 2001. a, b, c, d
Pullen, J., Doyle, J. D., Haack, T., Dorman, C., Signell, R. P., and Lee, C. M.: Bora event variability and the role of air-sea feedback, J. Geophys. Res.-Oceans, 112, C03S18 https://doi.org/10.1029/2006JC003726, 2007. a, b
Querin, S., Crise, A., Deponte, D., and Solidoro, C.: Numerical study of the role of wind forcing and freshwater buoyancy input on the circulation in a shallow embayment (Gulf of Trieste, Northern Adriatic Sea), J. Geophys. Res.-Oceans, 111, C03S16, https://doi.org/10.1029/2006JC003611, 2006. a, b, c, d
Querin, S., Cosoli, S., Gerin, R., Laurent, C., Malačič, V., Pristov, N., and Poulain, P.-M.: Multi-platform, high-resolution study of a complex coastal system: The TOSCA experiment in the Gulf of Trieste, J. Mar. Sci. Eng. 9, 5, https://doi.org/10.3390/jmse9050469, 2021. a, b, c, d
Rizzo, S., Rapisarda, A., and Group, C.: Environmental atmospheric turbulence at Florence airport, in: AIP Conference Proceedings, vol. 742, 176–181, American Institute of Physics, https://doi.org/10.1063/1.1846475, 2004. a, b
Schäfer, B., Heppell, C. M., Rhys, H., and Beck, C.: Fluctuations of water quality time series in rivers follow superstatistics, Iscience, 24, 102881, https://doi.org/10.1016/j.isci.2021.102881, 2021. a, b, c
Ursella, L., Čermelj, B., Ličer, M., and Martini, S.: HFR-NAdr (High Frequency Radar NAdr network), European HFRadar Node [data set], https://doi.org/10.57762/8RRE-0Z07, 2023. a
Weber, J., Reyers, M., Beck, C., Timme, M., Pinto, J. G., Witthaut, D., and Schäfer, B.: Wind power persistence characterized by superstatistics, Sci. Rep.-UK, 9, 1–15, 2019. a
Short summary
An increasing amount of data allows us to move from low-order moments of fluctuating observations to their PDFs. We found the analytical fat-tailed PDF form (a combination of Gaussian and two-exponential convolutions) for 2 years of sea surface current increments in the Gulf of Trieste, using superstatistics and the maximum-entropy principle twice: on short and longer timescales. The data from different wind regimes follow the same analytical PDF, pointing towards a universal behaviour.
An increasing amount of data allows us to move from low-order moments of fluctuating...
