Smoke ring. This is a toroidal (doughnut-shaped) vortex. It is caused by friction between moving air and the stationary air around it | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Lawry, Lawrence |
Taille de l’image : | 4201 px × 3332 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : | - |