Climatology of Cyclones, Anticyclones and Storm Tracks: Revision of Concepts

نویسندگان

  • David Mendes
  • Monica Damião Mendes
چکیده

This paper has the finality of describe climatology of extratropical cyclones, anticyclones and storm tracks for the NH and SH. There is a long history of studies on the characteristics of synoptic systems, beginning with classical work on mid-latitude cyclones. For the SH, analyses of pressure data provide extensive statistics of the climatology of synoptic systems. Interestingly, the anticyclones mean central pressure at 38 ̊S in JJA and 44 ̊S in DJF. SH cyclones are characterized in frequency maximum in the circumpolar trough between about 50 ̊S and 70 ̊S. For the NH cyclones, the principal findings of the analysis are as follows: In January the primary maxima are in the western North Atlantic, with a peak about 45 ̊ – 50 ̊N, where there is a secondary peak, over the north-central Mediterranean; These characteristics are similar in April but with decrease in the frequency of centers; In July the frequencies are further reduced and the hemisphere maximum is over eastern Canada at 55 ̊N; The October pattern resembles that of winter, except that the Atlantic maximum is off southeast Greenland.

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تاریخ انتشار 2007