|MadSci Network: Earth Sciences|
Lightning always produces thunder however there are a number of reasons why we may not hear it. Distance: As with other sounds, thunder fades as the sound wave moves through the air. Dissipation: Sound waves may bend upward (or downward) as they travel and not reach you even though you can see the lightning from which they initiated. The thunder clap may also dissipate within the chaos of the thunderstorm itself leaving decreasing the horizontal distance over which it can be heard. Environment: A sound wave bends when traveling through air with different temperatures. Thunderstorm clouds may be up to 12 miles high and envelope temperatures from 80 degrees at the surface to -20 or less at the top.
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