When you include observations of weather over the whole earth, you get
some pretty amazing numbers. Here are a couple-
Number of thunderstorms occurring at any given time: 2000
Number of lightning strikes over the earth per second: 100
(The above numbers from this web site:
http://www.lightningstalker.com/weather/lightningstalker/more.html)Expanding the lightning numbers... 100 per second equals 6000 strikes per
minute
6000 per minute equals
360,000 per hour
360,000 per hour equals
8,640,000 per day
Wendell Bechtold, meteorologist
Forecaster, National Weather Service
Weather Service Office, St. Louis, MO
A number of studies have been done using lightning detection networks
located in some countries and using a couple of satellites that have
optical detectors designed to recognize lightning flashes. The most recent
data suggests that the long used statistic of around 100 flashes per second
globally is close to being correct, of which 80% are in-cloud flashes and 20%
are cloud-to-ground flashes.
This gives us approximately 20 flashes to the ground per second globally and
therefore 1,728,000 flashes to the ground per day. This seems like a huge
number, but it is necessary to maintain an electrical balance between
the Earth's surface and the atmosphere.
David R. Cook
Atmospheric Physics and Chemistry Section
Environmental Research Division
Argonne National Laboratory
Source:
http://www.newton.dep.anl.gov/askasci/wea00/wea00239.htmNEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators.
Argonne National Laboratory, Division of Educational Programs, Harold Myron, Ph.D., Division Director.
Newton Home Page*****************************************************
A lightning flash is composed of a series of strokes with an average of about four. The length and duration of each lightning stroke vary, but typically average about 30 microseconds. (The average peak power per stroke is about 1012 watts.)
Source:
http://thunder.msfc.nasa.gov/primer/primer2.html----
...and to the discovery that the global flash rate is approximately 40 flashes per second, less than half of the widely accepted estimates dating back to 1925.
From this information, it is now estimated that over 1.2 billion lightning flashes (intracloud plus cloud-to-ground) occur around the world every year. Most of the lightning is in the InterTropical Convergence Zone (ITCZ) over the continents, and there is far more lightning over the land masses than over the oceans. This results from the stronger vertical motions in continental clouds than in oceanic clouds.
Source:
http://thunder.msfc.nasa.gov/otd/----
Lightning Safety Facts from NOAA. Each second there are 50 to 100 Cloud-to-Ground Lightning Strikes to the Earth world-wide.
How big around is a typical lightning bolt? Answer: About the size of a Quarter to Half-Dollar! Lightning looks so much wider than it really is just because its light is so bright! (I just thought this to be so interesting that I should add it. - DG)
Source:
http://www.stormwise.com/striking.htm----
I suppose the correct answer depends on how the question is interpreted. The phrase "ightning strikes on our planet" could mean lightning striking Earth or it could mean lightning striking within the Earth's atmosphere.
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Some odd facts I ran across -
Approximately 494,000 cloud to ground lightning flashes occur in Colorado every year. Colorado ranks 26th in the nation (Ron Holle, Global Atmospherics, quoted from the Rocky Mountain News, 30th June, 2001) -
Number of thunderstorms occurring at any given moment - 2000
Number of thunderstorms in the USA per year - 20 Million
On a clear night, lightning flashes from a distant storm can be seen hundreds of miles away.
Since 1960, lightning strikes have killed about the same number of Americans as terrorists have. (So have deer-related auto accidents and peanuts.)
