Influence of large-scale atmospheric circulation on controlling lightning over subtropical oceanic regions

F. I. SOLARI; M. GABRIELA NICORA; ÁVILA, ELDO E.; RENE GARREAUD

Tel Aviv

Conferencia; 17th International Conference on Atmospheric Electricity; 2022

Observed behaviour: lightning occurs ~10 times over land than overoceans (e.g. Williams & Stanfill, 2002)➢ Classic theories → “thermal theory” & “aerosol theory” (Williams &Stanfill, 2002) → supported by experiments over tropical and equatorialregions, process implies thermally forced air ascent → caveat: this cannotbe fully extrapolated to midlatitudes where meteorological systems havedifferent characteristics and air ascent is often dynamically forced➢ Subtropical oceanic regions → controlled by semi-permanent highpressure systems (see Fig. 1) → large-scale subsidence inhibitsconvection → but they can be disturbed by weather systems that cantrigger convection and lightning