Articles | Volume 17, issue 4
https://doi.org/10.5194/os-17-997-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-17-997-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Laboratory experiments on the influence of stratification and a bottom sill on seiche damping
Karim Medjdoub
von Kármán Laboratory of Environmental Flows; Eötvös Loránd University, Pázmány P. sétány 1/A, 1117 Budapest, Hungary
Imre M. Jánosi
Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Str. 38, 01187 Dresden, Germany
University of Public Service, Faculty of Water Sciences, Ludovika sqr. 1, 1083 Budapest, Hungary
von Kármán Laboratory of Environmental Flows; Eötvös Loránd University, Pázmány P. sétány 1/A, 1117 Budapest, Hungary
MTA-ELTE Theoretical Physics Research Group, Pázmány P. sétány 1/A, 1117 Budapest, Hungary
Related authors
No articles found.
Imre M. Jánosi, Holger Kantz, Jason A. C. Gallas, and Miklós Vincze
Ocean Sci., 18, 1361–1375, https://doi.org/10.5194/os-18-1361-2022, https://doi.org/10.5194/os-18-1361-2022, 2022
Short summary
Short summary
Surface flow fields of the global oceans are dominated by so-called mesoscale (50–300 km) eddies. They usually drift westward at a few kilometers per day, transporting mass, temperature, chlorophyll, and debris. There are several methods to identify and track eddies based on satellite measurements, some of them very computationally demanding. Here we extend a recently proposed simple procedure to the global scale, which gives quick coarse-grained statistics on mesoscale vortex properties.
Costanza Rodda, Uwe Harlander, and Miklos Vincze
Weather Clim. Dynam., 3, 937–950, https://doi.org/10.5194/wcd-3-937-2022, https://doi.org/10.5194/wcd-3-937-2022, 2022
Short summary
Short summary
We report on a set of laboratory experiments that reproduce a global warming scenario. The experiments show that a decreased temperature difference between the poles and subtropics slows down the eastward propagation of the mid-latitude weather patterns. Another consequence is that the temperature variations diminish, and hence extreme temperature events might become milder in a global warming scenario. Our experiments also show that the frequency of such events increases.
Imre M. Jánosi, Amin Padash, Jason A. C. Gallas, and Holger Kantz
Ocean Sci., 18, 307–320, https://doi.org/10.5194/os-18-307-2022, https://doi.org/10.5194/os-18-307-2022, 2022
Short summary
Short summary
Spectacular climatic phenomena such as El Nino—La Nina oscillations are connected with large-scale rearrangements of oceanic surface flow patterns. In order to get a better insight into the dynamics of such changes, we performed numerical experiments on the advection of 6600 water parcels in the focal area. Surface flow fields were taken from the AVISO data bank. A simple stochastic model (fractional Brownian motion) with only two parameters nicely reproduced the statistics of advection.
Imre M. Jánosi, Miklós Vincze, Gábor Tóth, and Jason A. C. Gallas
Ocean Sci., 15, 941–949, https://doi.org/10.5194/os-15-941-2019, https://doi.org/10.5194/os-15-941-2019, 2019
Short summary
Short summary
Mesoscale eddies are ubiquitous swirling flow patterns in the open ocean with diameters of around 100 km. They transport a huge amount of heat and material and are therefore key elements of the “weather” of the ocean. Using satellite-based ocean surface elevation, we found that the combined global effect of all mesoscale eddies can be treated as a single strong “super-vortex”. This finding can be helpful to estimate the energy budget of ocean regions where only sparse field data are available.
P. I. Orvos, V. Homonnai, A. Várai, Z. Bozóki, and I. M. Jánosi
Geosci. Instrum. Method. Data Syst., 4, 189–196, https://doi.org/10.5194/gi-4-189-2015, https://doi.org/10.5194/gi-4-189-2015, 2015
Short summary
Short summary
The remotely sensed drought severity index (DSI) records compiled by Mu et al. (2013) exhibit significant local trends in several geographic areas. Since the interpretation of DSI values and trends depend on several local factors, standard field significance tests cannot provide more reliable results than the presented local trend survey. The observed continent-wide trends might be related to a slow (decadal) mode of climate variability, a link to global climate change cannot be established.
Cited articles
Antenucci, J. P. and Imberger, J.: Energetics of long internal gravity waves in
large lakes, Limnol. Oceanogr., 46, 1760–1773,
https://doi.org/10.4319/lo.2001.46.7.1760, 2001. a, b
Antenucci, J. P. and Imberger, J.: The seasonal evolution of wind/internal wave
resonance in Lake Kinneret, Limnol. Oceanogr., 48, 2055–2061,
https://doi.org/10.4319/lo.2003.48.5.2055, 2003. a, b
Bell Jr., T. H.: Topographically generated internal waves in the open ocean, J.
Geophys. Res. (1896–1977), 80, 320–327,
https://doi.org/10.1029/JC080i003p00320, 1975. a
Boegman, L. and Ivey, G. N.: The dynamics of internal wave resonance in
periodically forced narrow basins, J. Geophys. Res.-Ocean., 117, C008134,
https://doi.org/10.1029/2012JC008134, 2012. a, b
Boschan, J., Vincze, M., Jánosi, I. M., and Tél, T.: Nonlinear
resonance in barotropic-baroclinic transfer generated by bottom sills,
Phys. Fluids, 24, 046601, https://doi.org/10.1063/1.3699062, 2012. a
Castillo, M. I., Pizarro, O., Ramírez, N., and Cáceres, M.: Seiche
excitation in a highly stratified fjord of southern Chile: the
Reloncaví fjord, Ocean Sci., 13, 145–160,
https://doi.org/10.5194/os-13-145-2017, 2017. a
Chapman, D. and Giese, G.: Seiches, in: Encyclopedia of Ocean Sciences, 2nd
Edn., edited by: Steele, J. H., Academic Press, Vol. 5, 344–350, Oxford,
https://doi.org/10.1016/B978-012374473-9.00128-4, 2001. a, b
Chapman, D. C. and Giese, G. S.: A model for the generation of coastal seiches
by deep-sea internal waves, J. Phys. Oceanogr., 20, 1459–1467,
https://doi.org/10.1175/1520-0485(1990)020<1459:AMFTGO>2.0.CO;2, 1990. a
Cushman-Roisin, B., Willmott, A. J., and Biggs, N. R.: Influence of
stratification on decaying surface seiche modes, Cont. Shelf Res., 25,
227–242, https://doi.org/10.1016/j.csr.2004.09.008, 2005. a, b
Davies, A. M., Xing, J., and Willmott, A. J.: Influence of open boundary
conditions and sill height upon seiche motion in a gulf, Ocean Dynam., 59,
863–879, 2009. a
de Carvalho Bueno, R., Bleninger, T., Yao, H., and Rusak, J. A.: An empirical
parametrization of internal seiche amplitude including secondary effects,
Env. Fluid Mech., 21, 209–237,
https://doi.org/10.1007/s10652-020-09767-1, 2020. a
French, A.: Vibrations and Waves, M.I.T. introductory physics series, Taylor &
Francis, available at: https://books.google.hu/books?id=RqE26vDmd5wC (last access: 23 July 2021), 1971. a
Garrett, C.: Internal tides and ocean mixing, Science, 301, 1858–1859,
https://doi.org/10.1126/science.1090002, 2003. a
Harris, C. R., Millman, K. J., van der Walt, S. J., Gommers, R., Virtanen, P.,
Cournapeau, D., Wieser, E., Taylor, J., Berg, S., Smith, N. J., Kern, R.,
Picus, M., Hoyer, S., van Kerkwijk, M. H., Brett, M., Haldane, A., del
Río, J. F., Wiebe, M., Peterson, P., Gérard-Marchant, P.,
Sheppard, K., Reddy, T., Weckesser, W., Abbasi, H., Gohlke, C., and Oliphant,
T. E.: Array programming with NumPy, Nature, 585, 357–362,
https://doi.org/10.1038/s41586-020-2649-2, 2020. a
Inall, M., Cottier, F., Griffiths, C., and Rippeth, T.: Sill dynamics and
energy transformation in a jet fjord, Ocean Dynam., 54, 307–314,
https://doi.org/10.1007/s10236-003-0059-2, 2004. a
Johnsson, M., Green, J. A. M., and Stigebrandt, A.: Baroclinic wave drag from
two closely spaced sills in a narrow fjord as inferred from basin water
mixing, J. Geophys. Res.-Ocean., 112, C003694,
https://doi.org/10.1029/2006JC003694, 2007. a
Lee, G. R., Gommers, R., Wasilewski, F., Wohlfahrt, K., and O'Leary, A.: PyWavelets: A Python package for wavelet analysis, J. Open Source Softw., 4, 1237, https://doi.org/10.21105/joss.01237,
2019. a
Lelong, M.-P. and Kunze, E.: Can barotropic tide – eddy interactions excite
internal waves?, J. Fluid Mech., 721, 1–27,
https://doi.org/10.1017/jfm.2013.1, 2013. a
Massel, S. R.: Internal gravity waves in the shallow seas, Springer, Springer International Publishing, Cham, Switzerland, 2015. a
Morozov, E. G.: Oceanic Internal Tides: Observations, Analysis and Modeling: A
Global View, Springer International Publishing, Cham,
https://doi.org/10.1007/978-3-319-73159-9, 2018. a
Münnich, M.: The influence of bottom topography on internal seiches in
stratified media, Dynam. Atmos. Ocean., 23, 257–266,
https://doi.org/10.1016/0377-0265(95)00439-4, 1996. a
Niiler, P. P.: On the internal tidal motions in the Florida Straits, Deep-Sea Res. Oceanogr. Abst., 15, 113–123,
https://doi.org/10.1016/0011-7471(68)90031-4, 1968. a, b
Park, J., MacMahan, J., Sweet, W. V., and Kotun, K.: Continuous seiche in bays
and harbors, Ocean Sci., 12, 355–368,
https://doi.org/10.5194/os-12-355-2016, 2016. a
Rattray Jr., M.: On the coastal generation of internal tides, Tellus, 12,
54–62, https://doi.org/10.1111/j.2153-3490.1960.tb01283.x, 1960. a, b
Rippeth, T. and Green, J. A. M.: Tides, the Moon and the kaleidoscope of ocean
mixing, in: Oceanography and Marine Biology – An Annual Review, Vol. 58,
edited by: Hawkins, S., Allcock, A., Bates, A., Evans, A., Firth, L., McQuaid,
C., Russell, B., Smith, I., Swearer, S., and Todd, P., CRC
Press, 319–350, available at: https://books.google.hu/books?id=Mp4FEAAAQBAJ (last access: 23 July 2021), 2020. a
Roget, E., Khimchenko, E., Forcat, F., and Zavialov, P.: The internal seiche field in the changing South Aral Sea (2006–2013), Hydrol. Earth Syst. Sci., 21, 1093–1105, https://doi.org/10.5194/hess-21-1093-2017, 2017. a
Staalstrøm, A. and Røed, L. P.: Vertical mixing and internal wave energy
fluxes in a sill fjord, J. Mar. Syst., 159, 15–32,
https://doi.org/10.1016/j.jmarsys.2016.02.005, 2016. a
Stanev, E. V. and Ricker, M.: Interactions between barotropic tides and
mesoscale processes in deep ocean and shelf regions, Ocean Dynam., 70,
713–728, https://doi.org/10.1007/s10236-020-01348-6, 2020. a, b
Stevens, K. N.: Acoustic Phonetics, MIT Press, London, 2000. a
Stigebrandt, A.: Barotropic and baroclinic response of a semi-enclosed basin to
barotropic forcing from the sea, in: Fjord Oceanography. NATO Conference
Series (IV Marine Sciences), Vol 4., edited by: Freeland, H., Farmer, D., and
Levings, C., Springer, Boston, MA, 141–164,
https://doi.org/10.1007/978-1-4613-3105-6_5, 1980. a
Stigebrandt, A.: Resistance to barotropic tidal flow in straits by baroclinic
wave drag, J. Phys. Oceanogr., 29, 191–197,
https://doi.org/10.1175/1520-0485(1999)029<0191:RTBTFI>2.0.CO;2, 1999. a
Stigebrandt, A. and Aure, J.: Vertical mixing in basin waters of fjords, J.
Phys. Oceanogr., 19, 917–926,
https://doi.org/10.1175/1520-0485(1989)019<0917:VMIBWO>2.0.CO;2, 1989. a
Vic, C., Naveira Garabato, A. C., Green, J. A. M., Waterhouse, A. F., Zhao, Z.,
Melet, A., de Lavergne, C., Buijsman, M. C., and Stephenson, G. R.:
Deep-ocean mixing driven by small-scale internal tides, Nat. Commun., 10,
2099, https://doi.org/10.1038/s41467-019-10149-5, 2019. a
Virtanen, P., Gommers, R., Oliphant, T. E., Haberland, M., Reddy, T.,
Cournapeau, D., Burovski, E., Peterson, P., Weckesser, W., Bright, J., van
der Walt, S. J., Brett, M., Wilson, J., Millman, K. J., Mayorov, N., Nelson,
A. R. J., Jones, E., Kern, R., Larson, E., Carey, C. J., Polat, İ., Feng,
Y., Moore, E. W., VanderPlas, J., Laxalde, D., Perktold, J., Cimrman, R.,
Henriksen, I., Quintero, E. A., Harris, C. R., Archibald, A. M., Ribeiro,
A. H., Pedregosa, F., van Mulbregt, P., and SciPy 1.0 Contributors:
SciPy 1.0: Fundamental Algorithms for Scientific Computing in Python,
Nat Method., 17, 261–272, https://doi.org/10.1038/s41592-019-0686-2, 2020. a
Wunsch, C. and Ferrari, R.: Vertical mixing, energy, and the general
circulation of the oceans, Annu. Rev. Fluid Mech., 36, 281–314,
https://doi.org/10.1146/annurev.fluid.36.050802.122121, 2004. a
Wynne, Z., Reynolds, T., Bouffard, D., Schladow, G., and Wain, D.: A novel
technique for experimental modal analysis of barotropic seiches for assessing
lake energetics, Environ. Fluid Mech., 19, 1527–1556,
https://doi.org/10.1007/s10652-019-09677-x, 2019. a
Xue, M.-A., Kargbo, O., and Zheng, J.: Seiche oscillations of layered fluids in
a closed rectangular tank with wave damping mechanism, Ocean Eng., 196,
106842, https://doi.org/10.1016/j.oceaneng.2019.106842, 2020. a, b
Short summary
In our laboratory experiments we addressed the question of how surface standing waves in a closed stratified basin are damped by the interaction of the flow in the bulk with a sill-like bottom obstacle reaching up to a density interface between the more saline deep layer and the freshwater layer at the top. We quantify the decay rates of the surface waves and explore what types of internal waves can be excited in this process along the internal density interface.
In our laboratory experiments we addressed the question of how surface standing waves in a...