ethicfail:Nature; No Photoshop required. 1. Lenticular Clouds 2. Anvil Clouds 3. Cirrus Kelvin-Hel
ethicfail: Nature; No Photoshop required. 1. Lenticular Clouds 2. Anvil Clouds 3. Cirrus Kelvin-Helmholtz Clouds 4. Fallstreak Hole 5. Mammatus Clouds 6. Polar Stratospheric Cloud 7. Roll Cloud 8. Undulatus Asperatus 9. Mammatus Clouds 10. Undulatus Asperatus -- source link