Remember Me
Or use your Academic/Social account:


Or use your Academic/Social account:


You have just completed your registration at OpenAire.

Before you can login to the site, you will need to activate your account. An e-mail will be sent to you with the proper instructions.


Please note that this site is currently undergoing Beta testing.
Any new content you create is not guaranteed to be present to the final version of the site upon release.

Thank you for your patience,
OpenAire Dev Team.

Close This Message


Verify Password:
Verify E-mail:
*All Fields Are Required.
Please Verify You Are Human:
fbtwitterlinkedinvimeoflicker grey 14rssslideshare1
Zahn, Matthias; Von Storch, Hans; Bakan, Stephan (2008)
Publisher: Co-Action Publishing
Journal: Tellus A
Languages: English
Types: Article
Polar lows are not properly resolved in global re-analyses. In order to describe the year-to-year variability and decadal trends in the formation of such mesoscale storms, atmospheric limited area models, which post-process re-analysis data, may be an appropriate tool. In this study we demonstrate the merits and potential of this approach. A series of 3-week long ensemble simulations of weather situations over the NE Atlantic with a limited area model/regional climate model (CLM) are examined. The model was driven with NCEP–NCAR re-analyses at the lateral and lower boundaries. Additionally, the spectral nudging technique was used to enforce the large-scale circulation, as given by the NCEP–NCAR reanalysis, on the simulation. The ensemble members differ by initial conditions taken from several consecutive days. In most of the cases, a polar low developed after a simulated time of about 2 weeks, that is, long after the initialization of the model calculations. The spectrally nudged version of the model is very insensitive to initial conditions. The observed polar lows were reproduced in all ensemble members. A reasonable correlation between the simulated polar low features and those derived from a satellite product (HOAPS-III) and operational high-resolution weather analyses (DWD) is found. The polar lows are considerably deepened compared to the driving NCEP–NCAR analysis, but the comparison with weather maps indicates some differences in detail. When CLM is run without the large-scale constraint of spectral nudging, considerable variability emerges across the different ensemble members and the observed polar low often does not emerge.
  • The results below are discovered through our pilot algorithms. Let us know how we are doing!

    • Andersson, A., Bakan, S., Fennig, K., Grassl, H., Klepp, C.-P. and coauthors. 2007. Hamburg ocean atmosphere parameters and fluxes from satellite data-hoaps-3-twice daily composite. Electronic publication: doi:10.1594/WDCC/HOAPS3 DAILY.
    • Blier, W. 1996. A numerical modeling investigation of a case of polar airstream cyclogenesis over the Gulf of Alaska. Mon. Wea. Rev. 124, 2703-2725.
    • Bo¨hm, U., Ku¨cken, M., Ahrens, W., Block, A., Hauffe, D. and co-authors. 2006. CLM - the climate version of LM: brief description and longterm applications. COSMO Newslett. 6, 225-235.
    • Bo¨hm, U., Ku¨cken, M., Hauffe, D., Gerstengarbe, F.-W., Werner, P., Flechsig and co-authors. 2004. Reliability of regional climate model simulations of extremes and of long-term climate. Nat. Hazards Earth Syst. Sci. 4, 417-431.
    • Bracegirdle, T. J. and Gray, S. L. 2006. The Role of Convection in the Intensification of Polar Lows. PhD Thesis. The University of Reading, UK, 69 pp.
    • Bracegirdle, T. J. and Gray, S. L. 2008. An objective climatology of the dynamical forcing of polar lows in the Nordic seas. Int. J. Climatol. doi:10.1002/joc.1686.
    • Bresch, J. F., Reed, R. J. and Albright, M. D. 1997. A polar-low development over the Bering Sea: analysis, numerical simulation, and sensitivity experiments. Mon. Wea. Rev. 125, 3109-3130.
    • Carleton, A. M. and Carpenter, D. A. 1990. Satellite climatology of “polar lows” and broadscale climatic associations for the Southern Hemisphere. Int. J. Climatol. 10, 219-246.
    • Claud, C., Heinemann, G., Raustein. E. and Mcmurdie, L. 2004. Polar low 'Le Cygne': satellite observations and numerical simulations. Quart. J. Roy. Meteor. Soc. 130, 1075-1102.
    • Condron, A., Bigg, G. R. and Renfrew, I. A. 2006. Polar Mesoscale Cyclones in the Northeast Atlantic: comparing Climatologies from ERA-40 and Satellite Imagery. Mon. Wea. Rev. 134, 1518-1533, doi:10.1175/MWR3136.1.
    • Davies, H. C. 1976. A lateral boundary formulation for multi-level prediction models. Quart. J. Roy. Meteorol. Soc. 102, 405-418.
    • De´que´, M., Jones, R., Wold, M., Giorgi, F., Christensen, J. and co-authors. 2005. Global high resolution versus limited area model climate change projections over Europe: quantifying confidence level from PRUDENCE results. Climate Dyn. 25, 653-670, doi:10.1007/s00382-005-0052-1.
    • Emanuel, K. A. 1986. An air-sea interaction theory for tropical cyclones. Part I: steady-state maintenance. J. Atmos. Sci. 43, 585-605.
    • Emanuel, K. A. and Rotunno, R. 1989. Polar lows as arctic hurricanes. Tellus 41A, 1-17.
    • Feser, F. 2006. Enhanced detectability of added value in limited area model results separated into different spatial scales. Mon. Wea. Rev. 134, 2180-2190.
    • Feser, F. and von Storch, H. 2005. A spatial two-dimensional discrete filter for limited area model evaluation purposes. Mon. Wea. Rev. 133, 1774-1786.
    • Feser, F., Weisse, R. and von Storch, H. 2001. Multi-decadal atmospheric modeling for Europe yields multi-purpose data. EOS Trans. 82, pp. 305, 310.
    • Grøna˚s, S. and Kvamstø, N. 1995. Numerical simulations of the synoptic conditions and development of arctic outbreak polar lows. Tellus 47A, 797-814.
    • Harold, J. M., Bigg, G. R. and Turner, J. 1999a. Mesocyclone activities over the north-east Atlantic. Part 1: vortex distribution and variability. Int. J. Climatol. 19, 1187-1204.
    • Harold, J. M., Bigg, G. R. and Turner, J. 1999b. Mesocyclone activities over the north-east Atlantic. Part 2: an investigation of causal mechanisms. Int. J. Climatol. 19, 1283-1299.
    • Harrold, T. W. and Browning, K. A. 1969. The polar low as a baroclinic disturbance. Quart. J. Roy. Meteorol. Soc. 95, 710-723.
    • Heinemann, G. 1998. A meso-scale model-based study of the dynamics of a wintertime polar low in the Weddell Sea region of the Antarctic during WWSP86. J. Geophys. Res. 103, 5983-6000.
    • Heinemann, G. and Klein, T. 2003. Simulations of topographically forced mesocyclones in the Weddell Sea and the Ross Sea region of Antarctica. Mon. Wea. Rev. 131, 302-316.
    • Kalnay, E., Kanamitsu, M., Kistler, R., Collins, W., Deaven, D. and coauthors. 1996. The NCEP/NCAR reanalysis project. Bull. Am. Meteorol. Soc. 77, 437-471.
    • Kolstad, E. 2006. A new climatology of favourable conditions for reverse-shear polar lows. Tellus 58A, 344-354, doi:10.1111/j.1600- 0870.2006.00171.x.
    • Lee, T.-Y., Park, Y.-Y. and Lin, Y.-L. 1998. A numerical modeling study of mesoscale cyclogenesis to the east of the Korean Peninsula. Mon. Wea. Rev. 126, 2305-2329.
    • Mailhot, J., Hanley, D., Bilodeau, B. and Hertzman, O. 1996. A numerical case study of a polar low in the Labrador Sea. Tellus 48A, 383-402.
    • Nielsen, N. W. 1997. An early Autumn polar low formation over the Norwegian Sea. J. Geophys. Res. 102, 13955-13973.
    • Nielsen, N. W. 1998. Om forudsigelighed af polare lavtryk (on the predictability of polar lows). Vejret 20, 37-48. (In Danish).
    • Nordeng, T. and Rasmussen, E. 1991. A most beautiful polar low. A case study of a polar low development in the Bear Island region. Tellus 44A, 81-99.
    • Rasmussen, E. 1979. The polar low as an extratropical CISK disturbance. Quart. J. Roy. Meteor. Soc. 105, 531-549.
    • Rasmussen, E. 1985. A case study of a polar low development over the Barents Sea. Tellus 37A, 407-418.
    • Rasmussen, E. and Turner, J. 2003. Polar Lows: Mesoscale Weather Systems in the Polar Regions. Cambridge University Press, Cambridge.
    • Steppeler, J., Doms, G., Scha¨ttler, U., Bitzer, H., Gassmann, A. and coauthors. 2003. Meso-gamma scale forecasts using the nonhydrostatic model LM. Meteorol. Atmos. Phys. 82, 75-96.
    • von Storch, H., Langenberg, H. and Feser, F. 2000. A spectral nudging technique for dynamical downscaling purposes. Mon. Wea. Rev. 128, 3664-3673.
    • Weisse, R., von Storch, H. and Feser, F. 2005. Northeast Atlantic and North Sea storminess as simulated by a regional climate model 1958- 2001 and comparison with observations. J. Climate 18, 465-479, doi:10.1175/JCLI-3281.1.
    • Wilhelmsen, K. 1985. Climatological study of gale-producing polar lows near Norway. Tellus 37A, 451-459.
    • Woth, K., Weisse, R. and von Storch, H. 2006. Climate change and north sea storm surge extremes: an ensemble study of storm surge extremes expected in a changed climate projected by four different regional climate models. Ocean Dyn. 56, 3-15, doi:10.1007/s10236- 005-0024-3.
    • Yanase, W., Fu, G., Niino, H. and Kato, T. 2004. A polar low over the Japan Sea on 21 january 1997. Part II: a numerical study. Mon. Wea. Rev. 132, 1552-1574.
    • Yanase, W., Niino, H. and Saito, K. 2002. High-resolution numerical simulation of a polar low. Geophys. Res. Lett. 29, 1658.
    • Zahn, M. and von Storch, H. 2006. Simulation of a Polar Low Case in the North Atlantic with Different Regional Numerical Models. WGNE report “Blue Book 2006”, 2pp.
  • No related research data.
  • No similar publications.

Share - Bookmark

Cite this article

Collected from