ISSN 2070-7401 (Print), ISSN 2411-0280 (Online)
Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa


Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2020, Vol. 17, No. 5, pp. 228-240

The baroclinic Rossby radius in the Nordic Seas

E.V. Novoselova 1 , T.V. Belonenko 1 , V.G. Gnevyshev 2 
1 Saint Petersburg University, Saint Petersburg, Russia
2 Shirshov Institute of Oceanology RAS, Moscow, Russia
Accepted: 08.10.2020
DOI: 10.21046/2070-7401-2020-17-5-228-240
In this paper, we analyze the baroclinic Rossby radius of deformation which is a fundamental term in oceanography. We also discuss the story of the term’s origin. The concept is found in the works by Bjerknes (1937) who was the first researcher to connect the dynamic characteristics of particles and the radius of surface curvature in synoptic structures. However, the analysis of dynamical equations by Bjerknes has rather a qualitative nature and refers to the atmosphere. This approach was further developed in the works by Carl Rossby who formulated it through the movement equations (Rossby, 1940). We also consider various approaches to numerical estimates of the deformation radius. Based on the ARMOR3D dataset, estimates of the baroclinic deformation radius for the Norwegian and the Greenland Seas are obtained and their spatial distribution is considered. The seasonal and interannual variability of the deformation radius is analyzed. It is shown that the Rossby radius in the studied area does not exceed 7–9 km on average. For most of the study area, the seasonal fluctuations in the radius are 1–2 km, with the greatest values of the radius being achieved in the warm season, and the smallest in the cold one. It was shown that bottom topography and convective processes play a significant role in the spatial and seasonal distribution of the Rossby deformation radius. An increase in both average and maximum values was revealed by the end of the 1993–2018 period.
Keywords: baroclinic Rossby radius, Lofoten basin, Norwegian basin, Greenland basin, ARMOR3D
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  1. Belonenko T. V., Kubryakov A. A., Stanichnyi S. V., Spektral’nye kharakteristiki voln Rossbi severo-zapadnoi chasti Tikhogo okeana po sputnikovym al’timetricheskim dannym (Spectral Characteristics of Rossby Waves in the Northwestern Pacific based on Satellite Altimetry), Issledovanie Zemli iz kosmosa, 2016, Vol. 1–2, pp. 43–52.
  2. Gill A., Dinamika atmosfery i okeana (Atmosphere-Ocean Dynamics), Vol. 2, Moscow: Mir, 1986, 415 p.
  3. Zinchenko V. A., Gordeeva S. M., Sobko Yu. V., Belonenko T. V., Mezomasshtabnye vikhri Lofotenskoi kotloviny po sputnikovym dannym (Analysis of mesoscale eddies in the Lofoten basin based on satellite altimetry), Fundamental’naya i prikladnaya gidrofizika, 2019, Vol. 12, No. 3, pp. 46–54, available at:
  4. Le Blond P. H., Mysak L. A., Volny v okeane (Waves in the Ocean), Moscow: Mir, 1981, 365 p.
  5. Novoselova E. V., Belonenko T. V., Izopiknicheskaya advektsiya v Lofotenskoi kotlovine Norvezhskogo morya (Isopycnal Advection in the Lofoten Basin of the Norwegian Sea), Fundamental’naya i prikladnaya gidrofizika, 2020, Vol. 13, No. 3, pp. 56–67, available at:
  6. Pedlosky J., Geofizicheskaya gidrodinamika (Geophysical Fluid Dynamics), Moscow: Mir, 1984, Vol. 1, 398 p., Vol. 2, 416 p.
  7. Stepanov D. V., Otsenka baroklinnogo radiusa deformatsii Rossbi v Okhotskom more, Meteorologiya i gidrologiya, 2017, Vol. 9, pp. 83–89.
  8. Travkin V. S., Belonenko T. V., Otsenka glubiny zimnei konvektsii v Lofotenskoi kotlovine Norvezhskogo morya i metody ee otsenki (Mixed layer depth in winter convection in the Lofoten Basin in the Norwegian Sea and assessment methods), Gidrometeorologiya i ekologiya, 2020, No. 59, pp. 67–83, available at:
  9. Fedorov A. M., Bashmachnikov I. L., Belonenko T. V., Lokalizatsiya oblastei glubokoi konvektsii v moryakh Severo-Evropeiskogo basseina, Labrador i Irminger (Localization of areas of deep convection in the Nordic seas, the Labrador Sea and the Irminger Sea), Vestnik Sankt-Peterburgskogo universiteta. Nauki o Zemle, 2018, Vol. 63, No. 3, pp. 345–362, available at:
  10. Fedorov A. M., Bashmachnikov I. L., Belonenko T. V., Zimnyaya konvektsiya v Lofotenskoi kotlovine po dannym buev Argo i gidrodinamicheskogo modelirovaniya (Winter convection in the Lofoten Basin according to ARGO buoys and hydrodynamic modeling), Vestnik Sankt-Peterburgskogo universiteta. Nauki o Zemle, 2019, Vol. 64, No. 3, pp. 491–511, available at:
  11. Alenius P., Nekrasov A., Myrberg K., Variability of the baroclinic Rossby radius in the Gulf of Finland, Continental Shelf Research, 2003, Vol. 23, No. 6, pp. 563–573, available at:
  12. Bjerknes J., Die Theorie der außertropischen Zyklonenbildung, Meteorologische Zeitschrift, 1937, Vol. 54, pp. 462–466.
  13. Cai S., Long X., Wu R., Wang S., Geographical and monthly variability of the first baroclinic Rossby radius of deformation in the South China Sea, J. Marine Systems, 2008, Vol. 74, No. 1–2, pp. 711–720, available at:
  14. Chelton D. B., deSzoeke R. A., Schlax M. G., El Naggar K., Siwertz N., Geographical variability of the first-baroclinic Rossby radius of deformation, J. Physical Oceanography, 1998, Vol. 28, pp. 433–460.
  15. Emery W. J., Lee W. G., Magaard L., Geographic and seasonal distributions of Brunt-Vaisala frequency and Rossby radii in the North Pacific and North Atlantic, J. Physical Oceanography, 1984, Vol. 14, pp. 294–317.
  16. Fennel W., Seifert T., Kayser B., Rossby radii and phase speeds in the Baltic Sea, Continental Shelf Research, 1991, Vol. 11(1), pp. 23–36, available at:
  17. Fer I., Bosse A., Ferron B., Bouruet-Aubertot P., The Dissipation of Kinetic Energy in the Lofoten Basin Eddy, J. Physical Oceanography, 2018, Vol. 48, pp. 1299–1316, available at:
  18. Gordeeva S., Zinchenko V., Koldunov A., Raj R. P., Belonenko T., Statistical analysis of long-lived mesoscale eddies in the Lofoten Basin from satellite altimetry, Space Research, 2020, available at:, (In press)
  19. Guinehut S., Dhomps A.-L., Larnicol G., Le Traon P.-Y., High resolution 3-D temperature and salinity fields derived from in situ and satellite observation, Ocean Science, 2012, Vol. 8, No. 5, pp. 845–857, available at:
  20. Houry S. E., Dombrowsky P., De Mey, Minster J.-F., Brunt-Väisälä Frequency and Rossby Radii in the South Atlantic, J. Physical Oceanography, 1987, Vol. 17, pp. 1619–1626, available at:<1619:BVFARR>2.0.CO;2.
  21. Köhl A., Generation and Stability of a Quasi-Permanent Vortex in the Lofoten Basin, J. Physical Oceanography, 2007, Vol. 37, pp. 2637–2651.
  22. Kurkin A., Kurkina O., Rybin A., Talipova T., Comparative analysis of the first baroclinic Rossby radius in the Baltic, Black, Okhotsk, and Mediterranean seas, Russ. J. Earth Science, 2020, Vol. 20, Art. No. ES4007, 29 p., available at:
  23. McDougall T. J., Barker P. M., Getting started with TEOS-10 and the Gibbs Seawater (GSW) Oceanographic Toolbox, 2011, 28 p.
  24. McDougall T. J., Feistel R., Wright D. G., Pawlowicz R., Millero F. J., Jackett D. R., King B. A., Marion G. M., Seitz S., Spitzer P., Chen C-T. A., The International Thermodynamic Equation of Seawater — 2010: Calculation and use of thermodynamic properties, Manuals and Guides No. 56, Intergovernmental Oceanographic Commission, UNESCO (English), 2010, 196 p.
  25. Meyer A., Sundfjord A., Fer I., Provost C., Robineau N. V., Koenig Z., Onarheim I. H., Smedsrud L. H., Duarte P., Dodd P. A., Graham R. M., Schmidtko S., Kauko H. M., Winter to summer oceanographic observations in the Arctic Ocean north of Svalbard, J. Geophysical Research: Oceans, 2017, Vol. 122, pp. 6218–6237, available at:
  26. Mulet S., Rio M.-H., Mignot A., Guinehut S., Morrow R., A new estimate of the global 3D geostrophic ocean circulation based on satellite data and in-situ measurements, Deep Sea Research. Part II: Topical Studies in Oceanography, 2012, pp. 70–81, available at:
  27. Nurser A. J. G., Bacon S., The Rossby radius in the Arctic Ocean, Ocean Science, 2014, Vol. 10, pp. 967–975, available at:
  28. Osinski R., Rak D., Walczowski W., Jan P., Baroclinic Rossby radius of deformation in the southern Baltic Sea, Oceanologia, 2010, Vol. 52, available at:
  29. Pawlowicz R., What every oceanographer needs to know about TEOS-10 (The TEOS-10 Primer), 2010, 10 p.
  30. Østerhus S., Turrell W. R., Hansen B., Lundberg P., Buch E., Observed transport estimates between the North Atlantic and the Arctic Mediterranean in the Iceland-Scotland region, Polar Research, 2001, Vol. 20, No. 2, pp. 169–175, available at:
  31. Raj R. P., The circulation of the Norwegian Sea — An investigation from space and ocean: Doctoral Thesis, University of Bergen, 2013, 173 p.
  32. Rossby C. G., On the mutual adjustment of pressure and velocity distributions in certain simple current systems. I, J. Marine Research, 1937, Vol. 1, pp. 15–28.
  33. Rossby C. G., On the mutual adjustment of pressure and velocity distributions in certain simple current systems. II, J. Marine Research, 1938, Vol. 2, pp. 239–263.
  34. Rossby C. G., Relation between variations in the zonal circulation of the atmosphere and the displacements of the semi-permanent centers of action, J. Marine Research, 1939, Vol. 2, pp. 38–55.
  35. Rossby C. G., Planetary flow patterns in the atmosphere, Quarterly J. Royal Meteorological Society, 1940, Vol. 66, pp. 68–87.
  36. Rossby T., Ozhigin V., Ivshin V., Bacon S., An isopyncal view of the Nordic Seas hydrography with focus on properties of the Lofoten Basin, Deep Sea Research. Part I: Oceanographic Research Papers, 2009, Vol. 56, pp. 1955–1971.
  37. Saenko O. A., Influence of Global Warming on Baroclinic Rossby Radius in the Ocean: A Model Intercomparison, J. Climate, 2006, Vol. 19, pp. 1354–1360, available at:
  38. Sueyoshi M., Yasuda T., Reproducibility and future projection of the ocean first baroclinic Rossby radius based on the CMIP3 multi-model dataset, J. Meteorological Society of Japan, 2009, Vol. 87, pp. 821–827, available at:
  39. Verbrugge N., Mulet S., Guinehut S., Buongiorno-Nardelli B., ARMOR3D: A 3D multi-observations T, S, U, V product of the ocean, Geophysical Research Abstracts, 2017, Vol. 19, EGU2017-17579.
  40. Volkov D. L., Kubryakov A. A., Lumpkin R., Formation and variability of the Lofoten basin vortex in a high-resolution ocean model, Deep Sea Research. Part I, 2015, Vol. 105, pp. 142–157, available at: