Ozone Layer is an atmospheric layer that is normally characterized by high ozone content which blocks most solar ultraviolet radiation from entry into the lower atmosphere. This natural sunscreen absorbs and blocks the majority of the sun’s UV radiation
. A layer of ozone gas acts as a shield encircling Earth and exists between 9.3 (15 kilometers) to 18.6 miles (30 kilometers) above its surface. It is between the stratosphere and troposphere. The ozone layer is filled with ozone, also known as 03
or trioxygen. Ozone is created when oxygen molecules (02
) are split by the sun into a duo of free-ranging oxygen atoms. When one of these free atoms bonds with a 02
molecule, a 03
molecule — ozone — is created.
Without this barrier in place, all of the radiation would reach Earth, damaging the DNA of plants and animals, like us humans. Even underwater life would not be safe since UV rays can penetrate clear water to a certain depth before being absorbed. Experts believe that for every 1% drop in ozone protection, there is an increase of around 2% in UV-B rays which get through to the planet’s surface. “Earth without the ozone layer is like a house without a roof.” Skin cancer rates would soar, but we might not even live long enough to experience that cause of death.
Within days of the ozone layer’s disappearance, many plants would die. The intensity of the sun’s radiation would make photosynthesis — a process by which plants convert light energy into chemical energy to fuel their growth — an impossibility for all but the largest and slowest-growing florae. And even these holdouts, primarily massive trees, would eventually die, too. Without plants, the food chain would collapse. Herbivores would starve. Omnivores and carnivores could feed off their bodies for a time, but their food supply would dwindle and cause widespread extinction.
Increased exposure to the sun’s radiation can also cause blindness and cataracts and, alarmingly, some experts now believe that the amount of protection we receive from vaccinations (for diseases such as measles) could be reduced in people exposed to higher levels of UV-B rays.
Depending on the level of exposure to the sun, effects can range from premature aging to certain kinds of skin cancer. Over the past decade, there has been a large increase in the number of people developing skin cancer but this could be attributed to the rise in the popularity of sunbathing over the past quarter-of-a-century rather than simply to reduced ozone levels.
Despite its protective powers, ozone isn’t necessarily stable, and it doesn’t take much to reduce ozone to its base elements. Take chlorofluorocarbons (CFCs), for example. When these synthetic chemicals, once used as refrigerants and aerosol-spray propellants, travel to the upper atmosphere they begin a chain reaction that spells disaster for the ozone layer. The CFCs are broken down by ultraviolet light and, as a result, release free chlorine atoms that attract oxygen atoms from ozone molecules. And what happens when you take an oxygen atom from ozone? It becomes oxygen. In this way, CFCs can make quick work of the ozone layer, which is why they have been placed under ever-tightening regulations over the past several decades, with a goal of eliminating their use completely later this century.
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