Modeling Wet Snow Accretion on Power Lines: Improvements to Previous Methods Using 50 Years of Observations

Bjørn Egil Kringlebotn Nygaard Norwegian Meteorological Institute, Oslo, Norway

Search for other papers by Bjørn Egil Kringlebotn Nygaard in
Current site
Google Scholar
PubMed
Close
,
Hálfdán Ágústsson Institute for Meteorological Research, University of Iceland, and Icelandic Meteorological Office, Reykjavík, Iceland

Search for other papers by Hálfdán Ágústsson in
Current site
Google Scholar
PubMed
Close
, and
Katalin Somfalvi-Tóth Hungarian Meteorological Service, Budapest, Hungary

Search for other papers by Katalin Somfalvi-Tóth in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

Methods to model wet snow accretion on structures are developed and improved, based on unique records of wet snow icing events as well as large datasets of observed and simulated weather. Hundreds of observed wet snow icing events are logged in detail in an icing database, most of which include an estimate of the mean and maximum diameter of observed icing on overhead power conductors. Observations of weather are furthermore available from a dense network of weather stations. The existing models for wet snow accretion on a standard cylinder are updated with realistic values for the terminal fall speed of wet snowflakes together with a snowflake liquid fraction–based criterion to identify wet snow. The widely used parameterization of the sticking efficiency is found to strongly underestimate the accretion rate. A calibrated parameterization of the sticking efficiency is suggested on the basis of long-term statistics of observed and modeled wet snow loads. Application of the improved method is demonstrated in a high-resolution simulation for a case of observed widespread and intensive wet snow icing in south Iceland. The results form a basis for mapping the climatology of wet snow icing in the complex terrain of Iceland as well as for preparing operational forecasts of wet snow icing and severe weather for overhead power transmission lines in complex terrain.

Corresponding author address: Bjørn Egil Kringlebotn Nygaard, Norwegian Meteorological Institute, Box 1022, Blindern N-0315 Oslo, Norway. E-mail: bjornen@met.no

Abstract

Methods to model wet snow accretion on structures are developed and improved, based on unique records of wet snow icing events as well as large datasets of observed and simulated weather. Hundreds of observed wet snow icing events are logged in detail in an icing database, most of which include an estimate of the mean and maximum diameter of observed icing on overhead power conductors. Observations of weather are furthermore available from a dense network of weather stations. The existing models for wet snow accretion on a standard cylinder are updated with realistic values for the terminal fall speed of wet snowflakes together with a snowflake liquid fraction–based criterion to identify wet snow. The widely used parameterization of the sticking efficiency is found to strongly underestimate the accretion rate. A calibrated parameterization of the sticking efficiency is suggested on the basis of long-term statistics of observed and modeled wet snow loads. Application of the improved method is demonstrated in a high-resolution simulation for a case of observed widespread and intensive wet snow icing in south Iceland. The results form a basis for mapping the climatology of wet snow icing in the complex terrain of Iceland as well as for preparing operational forecasts of wet snow icing and severe weather for overhead power transmission lines in complex terrain.

Corresponding author address: Bjørn Egil Kringlebotn Nygaard, Norwegian Meteorological Institute, Box 1022, Blindern N-0315 Oslo, Norway. E-mail: bjornen@met.no
Save
  • Admirat, P., 2008: Wet snow accretion on overhead lines. Atmospheric Icing of Power Networks, M. Farzaneh, Ed., Springer, 119–169.

  • Admirat, P., and Y. Sakamoto, 1988: Calibration of a wet-snow model on real cases in Japan and France. Proc. Fourth Int. Workshop on Atmospheric Icing of Structures (IWAIS), Paris, France, 7–13.

  • Ágústsson, H., and H. Ólafsson, 2007: Simulating a severe windstorm in complex terrain. Meteor. Z., 16, 111112.

  • Betts, A. K., 1986: A new convective adjustment scheme. Part I: Observational and theoretical basis. Quart. J. Roy. Meteor. Soc., 112, 677691.

    • Search Google Scholar
    • Export Citation
  • Betts, A. K., and M. J. Miller, 1986: A new convective adjustment scheme. Part II: Single column tests using GATE wave, BOMEX, and arctic air-mass data sets. Quart. J. Roy. Meteor. Soc., 112, 693709.

    • Search Google Scholar
    • Export Citation
  • Bonelli, P., M. Lacavalla, P. Marcacci, G. Mariani, and G. Stella, 2011: Wet snow hazard for power lines: A forecast and alert system applied in Italy. Nat. Hazards Earth Syst. Sci., 11, 24192431.

    • Search Google Scholar
    • Export Citation
  • Chen, F., and J. Dudhia, 2001: Coupling an advanced land surface–hydrology model with the Penn State–NCAR MM5 modeling system. Part II: Preliminary model validation. Mon. Wea. Rev., 129, 587604.

    • Search Google Scholar
    • Export Citation
  • Coles, S., 2001: An Introduction to Statistical Modeling of Extreme Values. Springer, 224 pp.

  • Dalle, B., and P. Admirat, 2011: Wet snow accretion on overhead lines with French report of experience. Cold Reg. Sci. Technol., 65, 4351.

    • Search Google Scholar
    • Export Citation
  • DeGaetano, A. T., B. N. Belcher, and P. L. Spier, 2008: Short-term ice accretion forecasts for electric utilities using the Weather Research and Forecasting Model and a modified precipitation-type algorithm. Wea. Forecasting, 23, 838853.

    • Search Google Scholar
    • Export Citation
  • Dudhia, J., 1989: Numerical study of convection observed during the winter monsoon experiment using a mesoscale two-dimensional model. J. Atmos. Sci., 46, 30773107.

    • Search Google Scholar
    • Export Citation
  • Elíasson, Á. J., and E. Thorsteins, 2007: Ice load measurements in test spans for 30 years. Proc. 12th Int. Workshop on Atmospheric Icing of Structures (IWAIS), Yokohama, Japan, Japanese Society of Snow and Ice, 6 pp.

  • Elíasson, Á. J., E. Thorsteins, and H. Ólafsson, 2000: Study of wet snow events on the south coast of Iceland. Proc. Ninth Int. Workshop on Atmospheric Icing of Structures (IWAIS), Chester, United Kingdom.

  • Elíasson, Á. J., E. Thorsteins, H. Ágústsson, and Ó. Rögnvaldsson, 2011: Comparison between simulations and measurements of in-cloud icing in test spans. Proc. 14th Int. Workshop on Atmospheric Icing of Structures (IWAIS), Chongqing, China, 7 pp.

  • Fikke, S., and Coauthors, 2007: COST Action 727: Atmospheric icing on structures, measurements and data collection on icing: State of the art. MeteoSwiss Publ. 75, 110 pp. [Available online at http://www.wmo.int/pages/prog/www/IMOP/meetings/Surface/ET-STMT-2/COST-727-report_MCH-V75.pdf.]

  • Finstad, K. J., S. M. Fikke, and M. Ervik, 1988: A comprehensive deterministic model for transmission line icing applied to laboratory and field observation. Proc. Fourth Int. Workshop on Atmospheric Icing of Structures (IWAIS), Paris, France, 227–231.

  • Frick, C., and H. Wernli, 2012: A case study of high-impact wet snowfall in northwest Germany (25–27 November 2005): Observations, dynamics, and forecast performance. Wea. Forecasting, 27, 12171234.

    • Search Google Scholar
    • Export Citation
  • Gumbel, E. J., 2004: Statistics of Extremes. Dover Publications, 375 pp.

  • Ísaksson, S. P., Á. J. Elíasson, and E. Thorsteins, 1998: Icing Database—Acquisition and registration of data. Proc. Eighth Int. Workshop on Atmospheric Icing of Structures (IWAIS), Reykjavík, Iceland, 235–240.

  • ISO, 2001: Atmospheric icing of structures. ISO 12494, Geneva, Switzerland, 56 pp.

  • Janjic, Z. I., 1994: The step-mountain eta coordinate model: Further developments of the convection, viscous sublayer and turbulence closure schemes. Mon. Wea. Rev., 122, 927945.

    • Search Google Scholar
    • Export Citation
  • Janjic, Z. I., 2002: Nonsingular implementation of the Mellor–Yamada level 2.5 scheme in the NCEP Meso model. NCEP Office Note 437, 61 pp.

  • Klinger, C., M. Mehdianpour, D. Klingbeil, D. Bettge, R. Häcker, and W. Baer, 2011: Failure analysis on collapsed towers of overhead electrical lines in the region Münsterland (Germany) 2005. Eng. Fail. Anal., 18, 18731883.

    • Search Google Scholar
    • Export Citation
  • Kollár, L. E., O. Ossama, and M. Farzaneh, 2010: Natural wet-snow shedding from overhead cables. Cold Reg. Sci. Technol., 60, 4050.

  • Liu, C., K. Ikeda, G. Thompson, R. Rasmussen, and J. Dudhia, 2011: High-resolution simulations of wintertime precipitation in the Colorado Headwaters region: Sensitivity to physics parameterizations. Mon. Wea. Rev., 139, 35333553.

    • Search Google Scholar
    • Export Citation
  • Makkonen, L., 1989: Estimation of wet snow accretion on structures. Cold Reg. Sci. Technol., 17, 8388.

  • Makkonen, L., 2008: Problems in the extreme value analysis. Struct. Saf., 30, 405419.

  • Makkonen, L., and B. Wichura, 2010: Simulating wet snow loads on power line cables by a simple model. Cold Reg. Sci. Technol., 61 (2–3), 7381.

    • Search Google Scholar
    • Export Citation
  • Mellor, G. L., and T. Yamada, 1982: Development of a turbulence closure model for geophysical fluid problems. Rev. Geophys. Space Phys., 20, 851875.

    • Search Google Scholar
    • Export Citation
  • Milbrandt, J. A., A. Glazer, and D. Jacob, 2012: Predicting the snow-to-liquid ratio of surface precipitation using a bulk microphysics scheme. Mon. Wea. Rev., 140, 24612476.

    • Search Google Scholar
    • Export Citation
  • Mlawer, E. J., S. J. Taubman, P. D. Brown, M. J. Iacono, and S. A. Clough, 1997: Radiative transfer for inhomogeneous atmosphere: RRTM, a validated correlated-k model for the longwave. J. Geophys. Res., 102, 16 663–16 682.

    • Search Google Scholar
    • Export Citation
  • Nygaard, B. E. K., J. E. Kristjánsson, and L. Makkonen, 2011: Prediction of in-cloud icing conditions at ground level using the WRF Model. J. Appl. Meteor. Climatol., 50, 24452459.

    • Search Google Scholar
    • Export Citation
  • Ólafsson, H., and S. H. Haraldsdóttir, 2003: Diurnal, seasonal, and geographical variability of air temperature limits of snow and rain. Proc. Int. Conf. on Alpine Meteorology and MAP-Meeting 2003, Vol. B, Brig, Switzerland, MeteoSwiss, 473–476. [Available online at http://www.map.meteoswiss.ch/map-doc/icam2003/ProceedingsB.pdf.]

  • Ólafsson, H., Á. J. Elíasson, and E. Thorsteins, 2002: Orographic influence on wet snow icing—Part I: Upstream of mountains. Proc. 10th Int. Workshop on Atmospheric Icing of Structures (IWAIS), Brno, Czech Republic, P4.31.

  • Podolskiy, E. A., B. E. K. Nygaard, K. Nishimura, L. Makkonen, and E. P. Lozowski, 2012: Study of unusual atmospheric icing at Mount Zao, Japan, using the Weather Research and Forecasting model. J. Geophys. Res., 117, D12106, doi:10.1029/2011JD017042.

    • Search Google Scholar
    • Export Citation
  • Poots, G., and P. L. I. Skelton, 1995: Thermodynamic models of wet-snow accretion: Axial growth and liquid water content on a fixed conductor. Int. J. Heat Fluid Flow, 16, 4349.

    • Search Google Scholar
    • Export Citation
  • Pytlak, P., P. Musilek, E. Lozowski, and D. Arnold, 2010: Evolutionary optimization of an ice accretion forecasting system. Mon. Wea. Rev., 138, 29132929.

    • Search Google Scholar
    • Export Citation
  • Rögnvaldsson, Ó., J. W. Bao, H. Ágústsson, and H. Ólafsson, 2011: Downslope windstorm in Iceland—WRF/MM5 model comparison. Atmos. Chem. Phys., 11, 103120.

    • Search Google Scholar
    • Export Citation
  • Sakakibara, D., Y. Nakamura, K. Kawashima, and S. Miura, 2007: Experimental result for snow accretion characteristics of communications cable. Proc. Int. Wire and Cable Symp. (IWCS), Lake Buena Vista, FL, 581–586.

  • Sakamoto, Y., 2000: Snow accretion on overhead wires. Philos. Trans. Roy. Soc. London, A358, 29412970.

  • Sakamoto, Y., and A. Miura, 1993: Comparative study of wet snow models for estimating snow load on power lines based on general meteorological parameters. Proc. Sixth Int. Workshop on Atmospheric Icing of Structures (IWAIS), Budapest, Hungary, 133–138.

  • Skamarock, W. C., and Coauthors, 2008: A description of the Advanced Research WRF version 3. NCAR Tech. Note NCAR/TN–475+STR, 125 pp.

  • Szyrmer, W., and I. Zawadzki, 1999: Modeling of the melting layer. Part I: Dynamics and microphysics. J. Atmos. Sci., 56, 35733592.

  • Thompson, G., R. Rasmussen, and K. Manning, 2004: Explicit forecasts of winter precipitation using an improved bulk microphysics scheme. Part I: Description and sensitivity analysis. Mon. Wea. Rev., 132, 519542.

    • Search Google Scholar
    • Export Citation
  • Thompson, G., P. Field, R. Rasmussen, and W. Hall, 2008: Explicit forecasts of winter precipitation using an improved bulk microphysics scheme. Part II: Implementation of a new snow parameterization. Mon. Wea. Rev., 136, 50955115.

    • Search Google Scholar
    • Export Citation
  • Thompson, G., B. E. Nygaard, L. Makkonen, and S. Dierer, 2009: Using the Weather Research and Forecasting (WRF) model to predict ground/structural icing. Proc. 13th Int. Workshop on Atmospheric Icing on Structures, Andermatt, Switzerland, 8 pp. [Available online at http://www.iwais2009.ch/fileadmin/user_upload/pictures/Session_3_cost_727_wg1.zip.]

  • Wakahama, G., 1979: Experimental studies of snow accretion on electric lines developed in a strong wind. Nat. Disaster Sci., 1, 2133.

    • Search Google Scholar
    • Export Citation
  • Yuter, S. E., D. E. Kingsmill, L. B. Nance, and M. Löffler-Mang, 2006: Observations of precipitation size and fall speed characteristics within coexisting rain and wet snow. J. Appl. Meteor. Climatol., 45, 14501464.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 1300 346 33
PDF Downloads 1082 301 27