Abstract
Sprites are the optical signatures of electrical discharges in the mesosphere triggered by large lightning strikes associated with thunderstorms. Since their discovery in the late 1980s, sprites have been observed extensively around the world, although very few observations of sprites from Africa have been documented in the literature. In this paper, we report the first ground-based recorded observations of sprites from South Africa. In 2 out of the 22 nights of observations (11 January and 2 February 2016), about 100 sprite elements were recorded from Sutherland in the Northern Cape, comprising different morphologies (carrot (55%), carrot/column (11%), unclassified (21%), column (13%)). The sprites were triggered by positive cloud-to-ground lightning strikes, which had an average peak value of ~74 kA and were observed at distances from ~400 km to 800 km. The estimated charge moment change of the lightning discharges associated with these events was in agreement with the threshold for dielectric breakdown of the mesosphere and correlates well with the observed sprite brightness.
 Significance: 
 
 The first ground-based recording of sprite events over southern Africa.
 It is suggested that the intensity of the events is proportional to the lightning stroke current.
Highlights
Such phenomena were noted by South African observers
Our analysis shows that, for the sprite events that were associated with their corresponding lightning strokes, the average lightning peak current associated with these sprite initiations was ~74 kA, and that the maximum and minimum current values were 191 kA and 11 kA, respectively
Sprites have been photographically recorded for the first time in southern Africa since the earliest sightings reported anecdotally in 1937
Summary
Anecdotal accounts of sporadic brief optical emissions appearing above thunderstorms have been found in the scientific literature for many years.[1,2,3,4] Such phenomena were noted by South African observers. In 1937, Malan[5] reported seeing a different kind of lightning in Johannesburg, at an approximate altitude of 50 km. He noted: On the evening of 2 January 1937, there was a long cloud bank about 100 km to the northeast. During the span of an hour and a half, a long and weak streamer of reddish hue appeared about ten times in the upper cloud simultaneously with a weak illumination of the same cloud. I assume the weak illumination was due to cloud-to-ground discharge (CG) behind the hills
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