Catatumbo lightning

   The Catatumbo Lightning (Spanish Relámpago del Catatumbo) is an atmospheric phenomenon in Venezuela. It occurs strictly in an area located over the mouth of the Catatumbo River where it empties into Lake Maracaibo. The frequent, powerful flashes of lightning over this relatively small area are considered to be the world's largest single generator of tropospheric ozone but not replenishing the ozone layer, as the latter is located in the stratosphere.
   It originates from a mass of storm clouds that create a voltaic arc at more than 5 km of height, during 140 to 160 nights a year, 10 hours per day and up to 280 times per hour. It occurs over and around Lake Maracaibo, typically over a bog area that forms where the Catatumbo River flows into the Venezuelan lake.
    The Catatumbo lightning usually develops between the coordinates 8 ° 30 'and 9 º 45' north latitude and 71 º and 73 º W.

   The phenomenon is characterized by almost continuous lightning, mostly within the clouds, which is produced in a large vertical development of clouds that form large electric arcs between 2 and 10 km in height (or more). The lightning tends to start approximately one hour after dusk.
  Among the major modern studies there is the one done by Melchor Centeno, who attributes the origin of the thunderstorms to closed wind circulation in the region.Between 1966 and 1970 the scientist Andrew Zavrostky with assistance from the University of Los Andes made three expeditions which concluded that the area would have several epicentres in the marshes of the Swamp National Park Juan Manuel de Aguas, Claras Aguas Negras and west Lake Maracaibo, and in 1991 he suggested that the phenomenon occurred due to cold and warm air currents meeting around the area. The study also speculated that an isolated cause for the lightning might be the presence of uranium in the bedrock.
   Between 1997 and 2000 Nelson Falcón conducted several expeditions and produced the first microphysics model of the Catatumbo Lightning identifying the methane produced by the swamps and the oil deposits in the area as a major cause of the phenomenon[8]. It has been noted to have little effects on local flora such as ferns, despite concerns.Historically the first written mention of the Catatumbo lightning was in the epic poem "La Dragontea" by Lope de Vega (1597) where the defeat of the English pirate or privateer Sir Francis Drake is narrated.
  The Prussian naturalist and explorer Alexander von Humboldt once described it as "electrical explosions that are like phosphorescent gleam". Italian geographer Agustin Codazzi described it as a "lightning that seems to arise from the continued Zulia river and its surroundings".
   The phenomenon became so celebrated that it was depicted in the flag and coat of arms of the state of Zulia, which contains Lake Maracaibo, and mentioned in the state's anthem.
   This phenomenon, for century popularly known as the Lighthouse of Maracaibo since its lights are visible for miles out at sea and the boats that sail the area navigate at night without any problems, e.g. from the lake (where no clouds usually occur at night).

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