Lake Maracaibo is South America’s largest lake, more than 13,000 sq kms of brackish water in northern Venezuela. It is also the most lightning-prone place on Earth. Early last year, a group of scientists identified the lake as the planet’s lightning hotspot, where thunderstorms occur on average 297 days a year.
A unique combination of topography and climatology produces perfect conditions for the development of thunderstorms over the lake. Being in the tropics, heat and humidity are at permanently high levels, and the lake sits in a large valley surrounded by the northernmost ridges of the Andes. Evening winds blowing down from the mountains drive air over the lake, warming it and creating convection. The resulting thunder clouds generate the most intense and predictable lightning in the world.
The scientists, from Nasa and the universities of São Paulo, Maryland and Alabama, tracked the distribution of lightning strikes using a sensor onboard a Nasa satellite that had been recording data since 1998. The resulting map showed the area with the highest strike rate — an annual average of 233 flashes per sq km — was not in the Congo basin as previously thought, but directly over Lake Maracaibo.