Hostname: page-component-cd9895bd7-jn8rn Total loading time: 0 Render date: 2024-12-25T04:40:05.968Z Has data issue: false hasContentIssue false
  • English
  • Français

Distribution of Jet Streams in the North Atlantic, Europe and the Mediterranean, 1957–8

Published online by Cambridge University Press:  18 January 2010

A. F. Crossley
A. F. Crossley
Affiliation:
(Meteorological Office)
Get access Rights & Permissions [Opens in a new window]

Extract

From an inspection of upper-air contour charts for 300 and 200 mb., the location of the axis of jet streams of 80 kt. or more has been assessed once daily over the two years 1957–8. Results are presented for each of the four seasons by means of isopleths of frequency (Fig. 1) and also by means of frequency-roses in areas of 5 degrees of latitude by 10 degrees of longitude (Figs. 2–5); each rose shows the number of occasions of direction of the axis from the eight compass points. The area covered extends from latitude 30° N. to 70° N., and from longitude 60° W. to 30° E. An Appendix contains some discussion of the technique of locating the axis of jet streams on contour charts.

The characteristics of jet streams were described in a paper by Chambers in this Journal for July/October 1959. The present paper goes a stage further by giving the number of occurrences of jet streams per season over a two-year period in an area from the North Atlantic to the Mediterranean. The number of occurrences depends very much on the chosen definition, about which there is no general agreement. Whilst a jet stream may be fairly described as a fast-moving stream of air in the upper troposphere with great extension in the direction of the wind and persistence of the order of days, for statistical purposes it is necessary to be more precise. In this paper a critical speed of 80 kt. is required at the 300- or 200-mb. level in order that the stream shall qualify as a jet stream. Further discussion of this point is given in the Appendix, but any definition is largely subjective and it does not matter a great deal what definition is used provided the reader is aware of the limits to which the statistics refer.

Type
Research Article
Information
The Journal of Navigation , Volume 14 , Issue 4 , October 1961 , pp. 432 - 445
Copyright
Copyright © The Royal Institute of Navigation 1961

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Campbell, W. J. (1958). The Arctic jet stream. Dept. of Met. and Climatology, University of Washington, Sc. Rep. No. 1.Google Scholar
Chambers, E. (1959). The jet stream. This Journal, 12, 266.Google Scholar
Endlich, R. M. and McLean, G. S. (1957). The structure of the jet stream core, J. Met., 14, 543.2.0.CO;2>CrossRefGoogle Scholar
Gilbert, G. H. (1945). Note on graphical methods for determining the curvature correction to the geostrophic wind, S.D.T.M. No. 98 (Copy available in M.O. Library).Google Scholar
Heastie, H. and Stephenson, P. M. (1960). Upper winds over the World, Parts I and II. Geophysical Memoirs, London, 13, no. 103.Google Scholar
Johnson, D. H. (1953). A further study of the upper westerlies, Quart. J. R. Met. S., 79, 402.CrossRefGoogle Scholar
Lamb, H. H., Fleming, J., Hoyle, H. D. and Robinson, J. (1957). Jet streams over North Africa and the central Mediterranean in January and February, 1954, Met. Mag., Lond., 86, 97.Google Scholar
Murray, R. (1953). Jet streams over the British Isles during June 14–18, 1951, Met. Mag., Lond., 82, 129.Google Scholar
Murray, R. and Johnson, D. H. (1952). Structure of the upper westerlies; a study of the wind field in the eastern Atlantic and western Europe in September, 1950, Quart. J. R. Met. S., 78, 186.CrossRefGoogle Scholar
Namias, J. and Clapp, P. J. (1951). Observational studies of general circulation patterns, Compendium of Met., Amer. Met. Soc, Boston, 551.CrossRefGoogle Scholar
Neiburger, M.et al. (1948). On the computation of wind from pressure data, J. Met., 5, No. 3, 87.2.0.CO;2>CrossRefGoogle Scholar
Palmén, E. (1951). The aerology of extratropical disturbances, Compendium of Met., Amer. Met. Soc, Boston, 599.CrossRefGoogle Scholar
Palmén, E. and Nagler, K. M. (1948). An analysis of the wind and temperature distribution in the free atmosphere over North America in a case of approximately westerly flow, J. Met., 5, No. 2, 58.Google Scholar
Palmén, E. and Nagler, K. M. (1949). The formation and structure of a large scale disturbance in the westerlies, J. Met., 6, No. 4, 227.2.0.CO;2>CrossRefGoogle Scholar
Palmén, E. and Newton, C. W. (1948). A study of the mean wind and temperature distribution in the vicinity of the polar front in winter, J. Met., 5, No. 5, 220.2.0.CO;2>CrossRefGoogle Scholar
Riehl, H., Alaka, M. A., Jordan, C. L. and Renard, R. J. (1954). The jet stream, Met. Monographs, 2, No. 7.Google Scholar
Sawyer, J. S. (1949). The significance of dynamic instability in atmospheric motions. Quart. J. R. Met. S., 75, 364.Google Scholar
Sawyer, J. S. (1950). The movement of jet streams and the wind hodograph, Met. Mag., Lond., 79, 357.Google Scholar
Serebreny, S. M., Wiegman, E. J. and Hadfield, R. G. (1957). A study of jet stream conditions in the northern hemisphere during winter, PAA Met. Dept., Tech. Rep. No. 5. See also Tech. Rep. No. 6 (summer), No. 7 (spring), and No. 8 (autumn).Google Scholar
Serebreny, S. M., Wiegman, E. J. and Hadfield, R. G. (1960). Models of jet stream structure. PAWA Inc., Pacific Alaska Div., Met. Dept., Tech. Rep. No. 9.Google Scholar
World Meteorological Organization (1958). Ninth session of the executive Committee Geneva, 24 September-14 October 1957. Abridged report with resolutions, Publication No. 67, R.C. 14, Geneva, p. 64.Google Scholar
Zobel, R. F. (1958). The evaluation of winds at 200 mb. from contour charts, Met. Mag., Lond., 87, 44.Google Scholar