Vapour Trail

Flight contrails over the French Alps, March 2007. These were pretty much the only clouds I saw on my skiing holiday this year. Exhaust from aircraft engines create contrails (condensation trails) which can develop into cirrus clouds that have an impact on the radiation balance of the Earth. The details is a complex balance between trapping and reflection of radiation; the net effect is a warming of the Earth's climate.

First you look so strong
then you fade away
you are a vapour trail
in a deep blue sky

Ride, Vapour Trail, Nowhere, 1990