Thanks for posting

Although these images are stunning from an artistic perspective, its shocking to realise how much we are killing the planet.”

To realise how much we are killing the planet perhaps it might be better to research the species extinction rates, the man-made pollution of our water cycle, the ground-based man-made pollution of our atmosphere that causes both global warming and global dimming, than infer mass extinction by water ice trails that are both formed from, and evaporate back into, the atmosphere.

The net effect of contrails is generally thought to increase nighttime temperatures and reduce daytime temperatures by the same amount – so it is roughly zero over time. It just makes for more boring skies…

…but these skies are local skies, local to where trails are. Seen from space, it’s the weather systems of the Earth that predominate, to the extent that the global effect of aircraft contrails is too insignificant to be measurable using even today’s satellite-based technology.

This is because the westbound planes need to fly 2000 feet higher over the beacon than eastbound ones.

With the increasing accuracy of instrumentation, this has been reduced to 1000 feet.
Personally I find this to be uncomfortably close, considering that the typical forward speed of cruising aircraft is 800 feet per second. A sneeze might put you where you might earnestly NOT wish to be….
Or someone else might make your mistake for you:

http://www.youtube.com/watch?v=0KWvtIsQ-Ck

http://b.imagehost.org/0587/ATC2.png

It is quite busy in the sky!