Final answer:
If we did not have an ozone layer, there would be no protection from UV rays, leading to increased health risks and ecological damage. The ozone layer absorbs most of the Sun's harmful UV radiation, thus safeguarding all forms of life on Earth.
Step-by-step explanation:
If we did not have an ozone layer, there would be no protection from UV rays. The ozone layer, which is a form of oxygen with three atoms per molecule (O3), plays a critical role in shielding the Earth from the Sun's ultraviolet (UV) radiation. The presence of ozone in the stratosphere, approximately 10 to 50 km above Earth, allows it to absorb most of the dangerous UV radiation, thus protecting living organisms from severe cell damage that UV light can cause.
Without the ozone layer, we would experience increased levels of UV radiation on Earth's surface. This scenario would lead to a host of problems, including higher rates of skin cancer, cataracts, damage to plant life, and disruption to the base of aquatic food webs due to the death of plankton. Moreover, the loss of ozone has been attributed to pollutants such as chlorofluorocarbons (CFCs), which have thankfully been phased out by international agreement, leading to a gradual recovery of the ozone layer.
While the absence of ozone would not directly affect the greenhouse effect, air pollution, or the presence of oxygen in the atmosphere, its role in protecting life on Earth from UV damage is undeniable and critical to the survival of many species, including humans.