ethicfail: Nature: No Photoshop required. 1. Lenticular Clouds2. Anvil Clouds3. Cirrus Kelvin-Helmholtz Clouds4. Fallstreak Hole5. Mammatus Clouds6. Polar Stratospheric Cloud7. Roll Cloud8. Undulatus Asperatus9. Mammatus Clouds10. Undulatus Asperatus