• ACSA, cited 2010: Cape Town International Airport, aircraft statistics. Airports Company South Africa. [Available online at www.acsa.co.za.]

  • Ahrens, C. D., 2000: Meteorology Today. Brooks/Cole, 528 pp.

  • ATNS, 2009: New radar statistics. Air Traffic and Navigation Services Standard Rep. ATM DIR 4/2009, ATM DIR 5/2009, and ATM DIR 7/2009.

  • Baars, J. A., Witiw M. , and Al-Habash A. , 2003: Determining fog type in the Los Angeles basin using historic surface observation data. Preprints, 16th Conf. on Probability and Statistics in the Atmospheric Sciences/13th Symp. on Global Change and Climate Variations, Long Beach, CA, Amer. Meteor. Soc., J3.8. [Available online at https://ams.confex.com/ams/pdfpapers/29133.pdf.]

  • Carter, T. J., 2005: The evolution of coastal lows along the south coast of South Africa. M.S. dissertation, Dept. of Geography and Environmental Studies, University of Zululand, KwaDlangezwa, South Africa, 165 pp.

  • Civil Aviation Authority, 2007: Operations specifications template. Form CA ACC-F-011. [Available online at www.caa.co.za.]

  • Croft, P. J., Pfost R. L. , Medlin J. M. , and Johnson G. A. , 1997: Fog forecasting for the southern region: A conceptual model approach. Wea. Forecasting, 12, 545556.

    • Search Google Scholar
    • Export Citation
  • Demarcq, H., Barlow R. G. , and Shillington F. A. , 2010: Climatology and variability of sea surface temperature and surface chlorophyll in the Benguela and Agulhas ecosystems as observed by satellite imagery. Afr. J. Mar. Sci., 25, 363372, doi:10.2989/18142320309504022.

    • Search Google Scholar
    • Export Citation
  • De Villiers, M. P., and Van Heerden J. , 2007: Fog at Abu Dhabi International Airport. Weather, 62, 209214.

  • Glickman, T., Ed., 2000: Glossary of Meteorology. 2nd ed. Amer. Meteor. Soc., 855 pp.

  • Hewitson, B. C., and Crane R. G. , 2002: Self-organizing maps: Applications to synoptic climatology. Climate Res., 22, 1326.

  • Hyvärinen, O., Julkunen J. , and Nietosvaara V. , 2007: Climatological tools for low visibility forecasting. Pure Appl. Geophys., 164, 13831396.

    • Search Google Scholar
    • Export Citation
  • ICAO, 2001: International standards and recommended practices: Attachment E. Annex 3 to the Convention on International Civil Aviation, International Civil Aviation Organization.

  • ICAO, 2010: Technical specifications related to meteorological observations and reports: Appendix 3. Annex 3 to the Convention on International Civil Aviation: Meteorological Service for International Air Navigation, 17th ed. International Civil Aviation Organization, APP 3-1–APP 3-5.

  • Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-Year Reanalysis Project. Bull. Amer. Meteor. Soc., 77, 437471.

  • Kohonen, T., 2001: Self-Organizing Maps. 3rd ed. Springer, 511 pp.

  • Kohonen, T., Hynninen J. , Kangas J. , and Laaksonen J. , 1996: SOM_PAK: The Self-Organizing Map Program package. Laboratory of Computer and Information Science Tech. Rep. A31, Helsinki University of Technology.

  • MeteoGraphics, 2010: Terra3D visualization software with bing terrain layer. MeteoGraphics. [Available at www.meteographics.de.]

  • Meyer, M. B., and Lala G. G. , 1990: Climatological aspects of radiation fog occurrence at Albany, New York. J. Climate, 3, 577586.

  • Miao, Y., Potts R. , Huang X. , Elliott G. , and Rivett R. , 2012: A fuzzy logic fog forecasting model for Perth Airport. Pure Appl. Geophys.,169, 1107–1119, doi:10.1007/s00024-011-0351-x.

  • Olivier, J., and Van Heerden J. , 1999: The South African Fog Water Collection Project. Water Research Commission Rep. 671/1/99., 149 pp. [Available from Library and Publications Division, Private Bag X03, Gezina 0031, South Africa.]

  • Pilié, R. J., Mack E. J. , Kocmond W. C. , Rogers C. W. , and Eadie W. J. , 1975: The life cycle of valley fog. Part I: Micrometeorological characteristics. J. Appl. Meteor., 14, 347373.

    • Search Google Scholar
    • Export Citation
  • Pilié, R. J., Mack E. J. , Kocmond W. C. , Rogers C. W. , and Katz U. , 1979: The formation of marine fog and the development of fog-stratus systems along the California coast. J. Appl. Meteor., 18, 12751286.

    • Search Google Scholar
    • Export Citation
  • Reusch, D. B., Alley R. B. , and Hewitson B. C. , 2005: Relative performance of self-organizing maps and principal component analysis in pattern extraction from synthetic climatological data. Polar Geogr., 29, 188212.

    • Search Google Scholar
    • Export Citation
  • SAWB, 1968: Aeronautical climatological summaries, 1957–1964. WB31, South African Weather Bureau, Pretoria, South Africa, 73 pp.

  • SAWB, 1996: Regional description of the weather and climate of South Africa: The weather and climate of the extreme south-western Cape. South African Weather Bureau, Pretoria, South Africa, 39 pp.

  • SAWS, 2010: Aeronautical climatological summaries, 1996–2010. Cape Town International Airport. CLS-CI-AERO-SUM-FACT-2010.001.2, South African Weather Service, Pretoria, South Africa, 30 pp.

  • Steyn, A. G. W., Smit C. F. , Du Toit S. H. C. , and Strasheim C. , 1994: Modern Statistics in Practice. J. L. Van Schaik, 761 pp.

  • Tardif, R., 2004: Characterizing fog occurrences in the northeastern United States using historical data. Preprints, 11th Conf. on Aviation, Range, and Aerospace Meteorology, Hyannis, MA, Amer. Meteor. Soc., P10.6. [Available online at https://ams.confex.com/ams/pdfpapers/81650.pdf.]

  • Tardif, R., and Rasmussen R. M. , 2007: Event-based climatology and typology of fog in the New York City region. J. Appl. Meteor. Climatol., 46, 11411168.

    • Search Google Scholar
    • Export Citation
  • Tennant, W., and Hewitson B. C. , 2002: Intra-seasonal rainfall characteristics and their importance to the seasonal prediction problem. Int. J. Climatol., 22, 10331048.

    • Search Google Scholar
    • Export Citation
  • Uppala, S. M., and Coauthors, 2005: The ERA-40 Re-Analysis. Quart. J. Roy. Meteor. Soc., 131, 29613012.

  • Van Schalkwyk, L., 2011: Fog forecasting at Cape Town International Airport: A climatological approach. M.S. dissertation, Dept. of Geography, Geoinformatics and Meteorology, University of Pretoria, 133 pp.

  • Weather Underground, cited 2010: Historic METAR data downloads. [Available online at www.wunderground.com.]

  • Willet, H. C., 1928: Fog and haze, their causes, distribution, and forecasting. Mon. Wea. Rev., 56, 435468.

  • World Airports, cited 2010: Cape Town International Airport, O.R. Tambo International Airport. [Available online at www.azworldairports.com.]

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 625 551 53
PDF Downloads 509 464 36

Climatological Characteristics of Fog at Cape Town International Airport

View More View Less
  • 1 Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Pretoria, and eTV (Pty) Ltd., Cape Town, South Africa
  • | 2 Department of Geography, Geoinformatics and Meteorology, University of Pretoria, Pretoria, South Africa
© Get Permissions Rent on DeepDyve
Restricted access

Abstract

The character of fog at Cape Town International Airport (CTIA), South Africa, is investigated, using 13 yr of historical hourly data during the period 1997–2010. Hourly surface observations are used to identify fog types that most frequently affect CTIA, by using an objective fog-type classification method that classifies fog events according to their primary formation mechanisms. Fog-type characteristics, such as the minimum visibility, duration, and time of onset and dissipation, are determined. Self-organizing maps (SOMs) are used to determine the dominant synoptic circulation types associated with fog at CTIA. Results show that radiative processes are the most common cause of fog, with an enhanced likelihood of radiation fog in winter. Cloud-base-lowering fog and advection fog events are more likely at the start of the fog season. As the fog season (March–August) progresses, synoptic circulations associated with fog change from a dominant low pressure pattern along the west coast in March and April to a dominant interior high pressure pattern toward July and August. The techniques presented may be used to provide aviation forecasters with a detailed description of the types of fog that frequently occur, their characteristics, and the synoptic circulation associated therewith.

Corresponding author address: Lynette van Schalkwyk, Dept. of Geography, Geoinformatics and Meteorology, Private Bag X20, Hatfield 0028, South Africa. E-mail: lynvanschalkwyk@gmail.com

Abstract

The character of fog at Cape Town International Airport (CTIA), South Africa, is investigated, using 13 yr of historical hourly data during the period 1997–2010. Hourly surface observations are used to identify fog types that most frequently affect CTIA, by using an objective fog-type classification method that classifies fog events according to their primary formation mechanisms. Fog-type characteristics, such as the minimum visibility, duration, and time of onset and dissipation, are determined. Self-organizing maps (SOMs) are used to determine the dominant synoptic circulation types associated with fog at CTIA. Results show that radiative processes are the most common cause of fog, with an enhanced likelihood of radiation fog in winter. Cloud-base-lowering fog and advection fog events are more likely at the start of the fog season. As the fog season (March–August) progresses, synoptic circulations associated with fog change from a dominant low pressure pattern along the west coast in March and April to a dominant interior high pressure pattern toward July and August. The techniques presented may be used to provide aviation forecasters with a detailed description of the types of fog that frequently occur, their characteristics, and the synoptic circulation associated therewith.

Corresponding author address: Lynette van Schalkwyk, Dept. of Geography, Geoinformatics and Meteorology, Private Bag X20, Hatfield 0028, South Africa. E-mail: lynvanschalkwyk@gmail.com
Save