The Earth is shielded by ozone from the sun's harmful ultraviolet (UV) rays. Life on Earth would be very challenging without the ozone layer in the atmosphere. Plants and planktons, which provide nutrition to the majority of ocean life, cannot survive or grow in the presence of extreme ultraviolet radiation. With a thinner Ozone Layer shield, humans would be more susceptible to skin cancer, cataracts, and immune system impairment.