50 years ago, the suns influence on Earths lightning was revealed

Lightning and the sun Science News, June 22, 1974

The latest addition to the growing list of meteorological phenomena which have been linked with solar activity is lightning. Using data from 1930 to 1973, [a researcher] reports in the May 24 Nature that in spite of year-to-year variations in the incidence of lightning, there is an underlying cyclic variation with a period of about 11 years which is in phase with the solar cycle.

Update

Multiple studies have linked upticks in lightning frequency with periodic fluctuations in the suns magnetic field. The connection isnt limited to these 11-year solar cycles. In 2018, scientists confirmed a trend related to one of the suns shorter cycles the 27 days our star takes to rotate around its axis. But how exactly the suns activity influences lightning is an enduring mystery. Perhaps the solar wind gives lightning a boost. When this stream of charged particles enters our atmosphere at high speeds, the average number of lightning strikes increases by over 30 percent for more than a month afterward, a 2014 study found.