Final answer:
There are two types of ozone: stratospheric ozone (good ozone), which forms a protective layer high in the atmosphere shielding Earth from ultraviolet radiation, and ground-level ozone (bad ozone), which contributes to smog and poses health risks. Stratospheric ozone is naturally occurring while ground-level ozone is formed by pollutants reacting in sunlight. Ozone depletion, primarily caused by man-made chemicals, damages this protective layer, leading to an increase in health and environmental risks.
Step-by-step explanation:
Ozone is a gas composed of three atoms of oxygen (O3). There are two distinct types of ozone, often referred to in terms of their location in the atmosphere and their effects on living things. The first type, known as stratospheric ozone, forms naturally in the upper atmosphere when ultraviolet light from the sun splits oxygen molecules, which then recombine to form ozone. This good ozone provides a vital protective layer, shielding Earth from harmful UV radiation which can cause skin cancer, cataracts, and damage to organisms such as plankton.
The second type of ozone, ground-level ozone, is not emitted directly into the air but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. This bad ozone is a primary component of urban smog and poses serious health risks to humans, animals, and plants, aggravating respiratory diseases and compromising the ability to breathe safely.
Unfortunately, this beneficial ozone layer is threatened by pollutants such as chlorine and bromine gases from man-made sources, leading to ozone depletion and the creation of ozone holes. This results in increased UV radiation reaching Earth's surface, heightening the risk of health issues and ecological disruptions.