During winters, the polar vortex at the North Pole expands, sending cold air southward. An ozone hole is the thinning of the ozone layer boosted in size by colder temperatures. As the temperatures high up in the stratosphere starts to rise, ozone depletion slows, the polar vortex weakens and breaks down.Jan 6, 2021
What is meant by ozone holes?
The term 'ozone hole' refers to the depletion of the protective ozone layer in the upper atmosphere (stratosphere) over Earth's polar regions.
What is ozone hole Ncert?
Ozone holes can be termed as the depletion of the ozone layer which is present in the upper atmosphere i.e. stratosphere at the polar region of earth. The ozone hole doesn't stop the radiation which is harmful to living things on earth and causes harmful effects such as health problems like skin cancer and eye damages.
How ozone hole is formed Upsc?
Formation: Polar vortex leads to the most depletion of stratospheric ozone. As winter arrives, a vortex of winds develops around the pole and isolates the polar stratosphere. When temperatures drop below -78°C (-109°F), thin clouds form ice, nitric acid, and sulphuric acid mixtures.
What is ozone hole and why it occurred?
The ozone hole has developed because people have polluted the atmosphere with chemicals containing chlorine and bromine. The primary chemicals involved are chlorofluorocarbons (CFCs for short), halons, and carbon tetrachloride.
What is ozone hole Class 6?
Ozone layer depletion is the thinning of the ozone layer present in the upper atmosphere. This happens when the chlorine and bromine atoms in the atmosphere come in contact with ozone and destroy the ozone molecules. One chlorine can destroy 100,000 molecules of ozone. It is destroyed more quickly than it is created.
Where is ozone hole found?
The ozone hole is not technically a “hole” where no ozone is present, but is actually a region of exceptionally depleted ozone in the stratosphere over the Antarctic that happens at the beginning of Southern Hemisphere spring (August–October).
What is ozone hole Class 11?
The ozone hole is the depletion of the ozone layer. The ozone layer absorbs the harmful UV rays coming from the sun and therefore does not allow those rays to reach Earth's surface. Consequences of ozone depletion: Due to its depletion, more radiation enters the Earth's atmosphere.
Why is the ozone hole in Antarctica Upsc?
The very low winter temperatures in the Antarctic stratosphere cause polar stratospheric clouds (PSCs) to form. Special reactions that occur on PSCs, combined with the relative isolation of polar stratospheric air, allow chlorine and bromine reactions to pro- duce the ozone hole in Antarctic springtime.
What is ozone layer importance?
The ozone layer protects the Earth against most UVB coming from the sun. It is always important to protect oneself against UVB, even in the absence of ozone depletion, by wearing hats, sunglasses, and sunscreen. However, these precautions will become more important as ozone depletion worsens.