Although at first they might look like a sierra crest viewed from an airplane, they are in fact cloud formations shot with an ultra-zoom lens, at dusk, sometime in late February 2009. Image by Evangelos Karageorgos, distributed by EGU under a Creative Commons License.
Imaggeo is the online open access geosciences image repository of the European Geosciences Union. Every geoscientist who is an amateur photographer (but also other people) can submit their images to this repository. Being open access, it can be used by scientists for their presentations or publications as well as by the press. If you submit your images to imaggeo, you retain full rights of use, since they are licenced and distributed by EGU under a Creative Commons licence.