Lightning is thought of as a chance event that appears wherever there is a storm. Over the mouth of the Catatumbo river in Venezuela it returns to the same corner night after night, with a steady seasonal pattern. What produces something like that?
A lake and a ring of mountains, on a nightly clock. Humid over the river mouth at night, and does the rest. Ridges of the Andes surround the basin on three sides and force the air up, to cool and condense into deep storm clouds. The seasonal pattern is relatively fixed, and the lightning does not burn continuously all year. Satellites found especially strong nocturnal activity in a small area, peaking after midnight.
Lightning returning night after night to the same corner looks like a mystery, and what distinguishes the place is not the power but the regularity of a .
At night humid winds converge over the area from the lake. The difference between the heat of the water and the heat of the land reverses every evening and feeds a wind in the same direction, so the engine itself is daily.
Mountain ridges surround the basin on three sides and force the air to rise, cool and condense into deep storm clouds. The mountains also fix the location, which is why the phenomenon is concentrated in a small area.
Satellites found especially strong nocturnal activity there, peaking in the hours after midnight. The seasonal pattern is relatively fixed, and the lightning does not burn continuously all year, with activity varying between years and in dry seasons. The popular is not needed: the winds and the mountains suffice.
wat. Catatumbo lightning returns at night when humid air from the lake is pushed upward by the mountains closing the basin.
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The place shows how a lake and mountains can lock a daily cycle of electrical storms into a local scale.
How do we know?
Satellite lightning sensors and ground networks counted flashes over years and compared them with winds, humidity and seasons.
What is still unknown
The activity varies from year to year and in dry seasons, and the popular methane explanation is not needed to create the storms.
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