The Frequency Of Thunderstorms

[Jane Louise]

Estimates of the frequency of thunderstorms around the world have been hard to pin down and may have been overstated for decades.

The European Geosciences Union has now tried to take a definitive stance and has found that the figure is likely on average to be about 760 thunderstorms per hour globally.

This is far fewer than, for example, the number estimated by he climatologist CEP Brooks, who in 1925 put it at about 1,800 per hour.

The data with which he was working, however, were incomplete, and an assumption that thunderstorms are evenly distributed over land and sea may have led to this overestimation. In fact, thunderstorms are much more likely to occur over the Earth’s land masses than its oceans.

The new number has the advantage of having been calculated by using a network of 40 monitoring stations around the world that are sensitive to lightning strikes. These comprise the World Wide Lightning Location Network (WWLLN).

However many lightning strikes there are it would take a pretty unlucky person to be hit by one even once in a lifetime, never mind on multiple occasions.

An American named Roy Cleveland Sullivan can probably therefore be counted as one of the least fortunate people ever to have lived. Between 1942 and 1977 he was struck by lightning seven times, landing him an unenviable place in the Guinness World Records and the title “Human Lightning Rodâ€.

In 1969, the second time he was hit, he had his eyebrows singed off, and the fourth strike, in 1972, burned his hair off. After that he took to carrying a pitcher of water with him. This would have come in useful in 1973 when he was caught for the fifth time, the lightning bolt tearing through his hat and setting his hair ablaze again.

Given that he worked as a ranger in ShenandoahNational Park, his outdoor existence meant that he was more likely than the average Joe to be caught in a storm but does not account for the extraordinary frequency with which lightning found him.

Even somebody standing atop a skyscraper during a thunderstorm dressed in a suit of armour and waving a golf club above his head might expect less risk. Mr Sullivan’s awful experiences brook no ready explanation.

By: Stephen Davenport

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