Distribution of lightning

The incidence of individual lightning strikes in any particular place is highly variable, but lightning does have an underlying spatial distribution. In 1997, NASA and National Space Development Agency (NASDA) of Japan launched the first Lightning Imaging Sensor (LIS)-equipped satellite to detect and record lightning.

Lightning is now known to occur on average 44 (± 5) times a second over the entire Earth, making a total of about 1.4 billion flashes per year.

The lightning flash rate averaged over the earth for intra-cloud (IC) + cloud-to-cloud (CC) to cloud-to-ground (CG) is at the ratio: (IC+CC):CG = 75:25. The base of the negative region in a cloud is normally at roughly the elevation where freezing occurs. The closer this region is to the ground, the more likely cloud-to-ground strikes are. In the tropics where the freeze zone is higher the (IC+CC):CG ratio is about 90:10. At the latitude of Norway (60° lat.) where the freezing elevation is lower the (IC+CC):CG ratio is about 50:50.

The map on the right shows that lightning is not distributed evenly around the planet. About 70% of lightning occurs on land in the Tropics, where the majority of thunderstorms occur. The north and south poles and the areas over the oceans have the fewest lightning strikes. The place where lightning occurs most often (according to the data from 2004 to 2005) is near the small village of Kifuka in the mountains of eastern Democratic Republic of the Congo, where the elevation is around 975 metres (3,200 ft). This region received 158 lightning strikes per 1 square kilometer (409 per sq mi) a year.

Above the Catatumbo river, which feeds Lake Maracaibo in Venezuela, Catatumbo lightning flashes several times per minute and has the highest number of lightning per square kilometer in the world. Singapore has one of the highest rates of lightning activity in the world. The city of Teresina in northern Brazil has the third-highest rate of occurrences of lightning strikes in the world. The surrounding region is referred to as the Chapada do Corisco ("Flash Lightning Flatlands").

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Wikipedia