Highway to Paradise by Sara Jazbar
Photo location: Črni Kal, Slovenia
Camera: Nikon D500
Two or three times each year, Črni Kal, a small town in Slovenia, experiences a temperature inversion which places fog under the highway bridge. When Sara first arrived, there was a wall of fog, and the visibility was reduced to just a couple of metres. However, after waiting a few hours, this beautiful scene appeared. "The fog stopped under the bridge and lingered there, flowing, moving, as if alive".
Fog is a low cloud that forms at the surface. The relative humidity is above 95%, and visibility is reduced to less than 1,000 metres. Fog is caused by tiny water droplets suspended in the air, and there are a few different types of fog: radiation fog, valley fog, advection fog, hill fog and evaporation fog.
In the troposphere, the lower part of the atmosphere where most of our weather happens, the temperature typically decreases with height. However, sometimes a smaller layer can form where the temperature increases with height; this layer is called a temperature inversion. Inversions usually happen in areas of high pressure, where the air descends towards the ground, and as it falls, it dries out and warms up. This warm layer of air can act as a lid and trap the cooler air, low clouds, and fog near the surface.
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