The Ozone Hole Story - Antarctica and Arctic polar regions

Another environmental trouble that gets a lot of headlines is ozone depletion. Ozone is a gas that’s made of molecules formed by three oxygen atoms. The oxygen we breathe is made of two oxygen atoms. When it’s close to the ground, ozone is toxic and unwanted, but up in the stratosphere, we need ozone to protect the earth from the sun’s ultraviolet rays.
The ozone layer surrounding the globe is getting thinner everywhere, but in some places it’s worse than others. There’s a significant thinning that occurs seasonally over Antarctica. It’s not an actual “hole” really, just super-thin ozone. But it’s referred to as a hole.

What is the Ozone Hole Story?

During spring in Antarctica, September through November, up to 60 percent of the ozone in the stratosphere is lost above the big, icy continent. Why in the spring? During the winter, Antarctica has the coldest temperatures in the world and receives no sunlight. Strong, swirling winds create clouds that release chlorine into the atmosphere. When the sun hits the chlorine in the spring, it goes to work tearing apart ozone molecules.
Later as the winds calm and the temperature rises, the ozone grows thicker again. Scientists worry that more “holes” will open up in the ozone around the world, and that some day they may not thicken back up.
Something similar happens in the Arctic polar regions. It’s called a “dimple” since it’s not as severe as Antarctica’s ozone loss.

What causes Ozone Depletion?

When certain gases, such as chlorine, enter the atmosphere, they tear apart the ozone molecules. The big culprits are chlorofluorocarbons (CFCs), chemicals made of chlorine, fluorine, and carbon. When CFCs were invented in the 1930s, they were considered wonder chemicals. They were cheap and easy to produce, so CFCs were used in many different products, such as propellants in spray cans (like hair spray, bug spray, and deodorant) and to make foam food packaging and other things made from Styrofoam. By the early 1970s, however, scientists realized that those CFCs were floating up into the atmosphere, and what was happening up in the stratosphere was cause
for alarm.

Updates to Ozone Hole Story:

A new study has revealed that an asteroid (as small as 1Km wide) striking in one of the Earth's oceans could cause a destructive chemical reaction that would wipe out half the ozone layer in stratosphere. The ozone layer helps protect the humans and living beings on earth from sun's harmful ultra violet radiations which it filter out before reaching the earth surface.

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