Beyond Horizons

Cantavieja – Comaloforno | 255 km.


By Juanjo Diaz de Argandoña
Camera Nikon D5100 @ ISO160 – 1/400
Lens ED80 APO Refractor Telescope
Date December 22nd 2014 – 09:09
Moving moutains, or refration doing its job in long distance pictures.
The above images show the very same mountains on the same day, just separated by a handful of minutes. In this time the layers of air are moving enough to change the direction of the beams of light, thus modifying the layout of the complete view.
As you can see, it almost seems that the mountains are growing in seconds!

Ulrich Deuschle has a simulation of the view here, where we can see how is the real looking of this mountains system:

View from Cantavieja looking North to Comaloforno at 255 km.

The synoptical situation this morning was very good for distant mountain observation, as Spain was just in the middle of one of the strongest High pressure systems ever recorded above our country.

This High pressure system allowed very clear air from the upper layers of the atmosphere to sink into the surface, in a process called Subsidence. Also related to it, is the accumulation of colder air in “pools” near the surface, producing the typical fog and mist of winter mornings. Meanwhile, the sinking air above is clear and perfect for our observations.

Synoptical situation on the morning of the observation. Credits: / GFS

As the atmosphere is getting more and more stable due to the High pressure system, the air is layered in its different temperatures and compositions. Moreover, the light travels differently depending on the air temperature, and as the layers are moving in the atmosphere, the combination of both creates the changing figures in the mountain shown above.