Scientists from Brazil have recently recorded a moment where lightning bolts can be seen getting attracted towards upward discharges from buildings. Marcelo MF Saba, a senior researcher at the National Institute for Space Research in Brazil (INPE) and PhD candidate Diego Rhamon have caught the incident on camera. The scientists captured the event with the help of high-speed video cameras at a very high resolution. The stunning event was recorded and photographed in the city of São José dos Campos. A total of 31 upward discharges were successfully captured. The scientists were 137.16 metres away from the lightning strikes. They managed to reveal what happens before the charge from the rod meets the charge from the lightning bolt.
The study and photos of this incident were published in Geophysical Research Letters – agupubs.onlinelibrary.wiley.com/doi/10.1029/2022GL101482 – last December.
These discharges were reportedly not just produced by the lightning rods, but also the many corners of the buildings along with other high spots. Saba told New York Times, “Any person standing in an open area can similarly launch an upward connecting discharge from their head or shoulders and be injured by lightning even when not directly struck by it.”
When Saba was asked if one kind of lightning rod offers better protection than the another, he replied saying some salesmen say that their lightning rods are better, but it is just sales talk. He went on to add that there is no concrete research done on this. According to him, there are standards that are needed to be followed by installing lightning rods and this is the best they can do for now.
Saba told Scienmag that lightning strikes can be as long as 100 km and transport currents as strong as 30,000 amps, which is equivalent to the current utilised by 30,000 bulbs of 100 watts simultaneously. He went on to add that the current can reach 300,000 amps in some cases. He added that the temperature of a usual lightning strike is 30,000 °C, which is five times hotter than the Sun’s surface. Saba explained that lightning rods don’t attract or repel the strikes, they simply provide lightning an easy and safe way to the ground.