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Name: Brian
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 2000-2001

When lighting hits water (ocean) how many miles are effected by the electrical path


This is a very good question, which is not easy to answer. I know of no measurements of this. However, the horizontal distance that the lightning energy would travel across the surface would depend on the intensity (current) of the lightning and how deep the water is where the stroke hit the water. Water is a fairly good conductor of electrical energy. If you dropped a 120 volt AC line into an 18 foot diameter, 3 foot deep home swimming pool, you very well may be killed. In the case of lightning, multiply the electrical current by thousands, and for the ocean multiply the volume by as much as millions.

My guess is that the average lightning strike would electrify a few hundred feet worth of water from it's strike point sufficiently to electrocute someone. However, some current is probably for up to a mile before it is fully dissipated.

Great question. Thanks Brian.

David Cook
Lightning researcher at Argonne National Laboratory

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