Recent satellite data suggests that there are more than 3 million lightning flashes worldwide per day, or more than 30 flashes per second on average. This includes flashes within or between clouds as well as flashes extending from cloud to ground. The amount of lightning found by satellites is considerably less than scientists once thought existed across the planet.
The most accepted global measure of lightning frequency is the thunderstorm day--a day on which thunder is heard at a reporting site. By this standard, the tropics are the earth's lightning capital. From 100 to 200 thunderstorm days are reported each year across the equatorial belt from South America to Africa, southeast Asia, and northern Australia.- However, thunderstorm days are not the ideal index of lightning, since this measure does not distinguish between a single clap of thunder and a prolonged severe storm.
On average, lightning strikes kill about 100 Americans each year, more than hurricanes, tornadoes, or any other single kind of bad weather except floods. Some studies have shown that U.S. lightning deaths may be under reported by 20 to 30% and lightning injuries by more than 40%. The lightning death toll has dropped from its 1940 level of 400 a year as people moved from rural to urban settings. Recently it has held constant, due to an increase in outdoor recreation.
According to the National Lightning Safety Institute, people under the age of 35 represent some 85% of lightning victims. One out of five strike victims die, and 70% of those who survive suffer serious long-term after effects.Source: The Agencies
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