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Burze w Hornsundzie (SW Spitsbergen)

Soroka J., Bania M.

Problemy Klimatologii Polarnej

2013

Nr 23

137--146

W pracy opisano przypadki burz zanotowane w Polskiej Stacji Polarnej w Hornsundzie w latach 1983-2012. W tym okresie zaobserwowano zaledwie siedem dni z burzą. Z każdym zaobserwowanym zjawiskiem wyładowań atmosferycznych powiązano przebieg wybranych elementów meteorologicznych oraz sytuację synoptyczną i typ cyrkulacji. Burze w Hornsundzie obserwowano jako epizody z co najwyżej kilkoma wyładowaniami atmosferycznymi. Zjawiska te związane były zazwyczaj z aktywnymi frontami chłodnymi napływającymi z południa i południowego-zachodu. Uzupełnieniem opisu burz są relacje osób, które przeżyły burze na Spitsbergenie.

The thunderstorms are very rare phenomena in polar regions. This paper present an analysis of occurrence of atmosphere lightning observed at Polish Polar Station Hornsund (Spitsbergen) over the last 30 years (1983-2012). During this period only seven thunderstorms occurred (20 December 1984, 5 March 1985, 9 September 1985, 26 March 1990, 24 November 1993, 5 and 8 August 1997). For each cases a course of meteorological parameters, synoptic situations and type of circulation were described. Thunderstorms at Hornsund are in most cases a short event with a few lightning. This phenomena were usually caused by strong cold front, which comes from south and southwest.

Some observations of bipolar flashes during summer thunderstorms near Warsaw

Barański P., Bodzak P.

Acta Geophysica

2006

Vol. 54, no. 1

71-89

Lightning discharges monitored by the SAFIR network system in Poland have been additionally identified over the 100×100 km area near Warsaw by single-point independent recordings of electric field and Maxwell current rapid changes. The data collected in summer thunderstorm days of 2002 showed some untypical properties of the lightning discharges which are rarely observed. Especially remarkable was a number of ground multistroke flashes with the return strokes (RS) which transported to the earth charges of opposite signs. Bipolar flashes (BF) of this kind were mostly involved in the events in which the nearby intracloud (ic) and cloud-to -ground (c-g) discharges were very closely associated in time. Events of such a close collocation of two different types of lightning discharges, previously called the complex lightning discharge events (CLDE), were quite often observed during summer thunderstorms in Poland. The events of this kind, i.e. 8 flashes, identified by the SAFIR detection system as BF’s present the multiple stroke flashes of the mean horizontal separation distance between striking points of particular RS equal to (2.8 š 2.1) km and of the mean time interval between strokes of (46.8 š 74.4) ms. The time separation between the observed BF and the adjacent ic flashes was from 0.1 to 335 ms, and horizontal separation distance between them ranged from 1.8 to 14.5 km. The mul-tiplicity of the recorded BF’s ranged from 2 to 4 strokes. Four of these BF’s followed the ic discharge, but the other three preceded the ic and one was alone with no close ic.