Ps 135:7 "The Lord Jesus causes the vapours to ascend from the ends of the earth, He makes lightning for the rain, He brings the wind out of His treasuries"

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Ground Flash Density

Over voltage damage caused by spikes and transients occurring in the form of lightning, utility switching, isolation arcing, electrical motor cycling, or any other sudden change in electrical power flow on AC power lines is said to be responsible for a third of all outages. The damage is caused by the sudden shock to the system which has not been designed for the higher voltage under the current design parameters and constraints. The sharp rise in voltage moves across the surface of the conductor, creating orifices in the insulation, breaking down the insulation co-ordination between phases. The breakdown in insulation, causes the system voltage to move across the electrical fields allowing the system frequency to cause a deep, prolonged type of damage to equipment associated with burning.

Ground Flash Density

Ground Flash Density is a measurement of the number of lightning strikes to ground, over a period of one year, averaged by the countries landmass per km2. It is known that only about 25 percent of lightning strikes are cloud-to-ground. The rest are either cloud-to-cloud or intra cloud.

Ground Flash Densities differ from region to region over the landmass of a country and thus some areas will be affected more seriously than others. A scale of 1 (minimum)  14 (maximum) is a comprehensive measurement of GFD.

GFD is highly correlated to thunderstorm duration or flash hours and enhanced by the topographies of the countries landmass. The lower the number of thunderstorms per year would then yield less Ground flash density. Sea breeze convection over the land plays a role as seen in the example of Florida and the Gulf coasts of the USA. In South Africa, the Northern Kwa-Zulu region is a hotspot and the Highveld regions yield by far some of the highest GFD in the world. The number of thunderstorms that occur in these regions is a direct relationship to the ground flash density.

Below are some GFD photos indicating the various degrees of density. Darker areas like orange, red and black indicate intense lightning areas, whilst lighter areas like yellow, green, blue low levels of lightning activity.

Satellite image - World Lightning Density

World Lightning Activity chart

The number of thunderstorms is in indicated in the colour coded chart below.

The yellow areas indicating low levels and blue areas indicating higher lightning dense regions. Areas with the highest lightning activty are, Central Africa, South America, Southern states of North America and South East Asia. South Africa, falls into an area with a relatively large number of thunderstorms per annum.

GFD Map of Africa

A lightning flash density map, taken of the Earth with Africa as the focal point.

The Central belt around the equator, has very high rainfall and highest levels of lightning in the world. The highest levels are seen in the Congo and Gabon where the black spot spreads out into red and orange rings.

As we move away from the equator to more temperate regions, lightning activity seems to decrease. These red and orange rings are still relatively high compared to the light yellow and green areas.

This is contrasted by a total lack of lightning over the Sahara desert in countries such as Mauritania, Algeria, Libya, and the Somalian Peninsula, indicated in blue, green and white.

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