Polar Vortex: A major contributor to depletion of ozone layer

Polar Vortex: A major contributor to depletion of ozone layer

Question-Polar vortex contributes in the depletion of ozone layer. What is Polar Vortex and what role does it play in the absence of Arctic Hole compared to the Antarctica Hole?

- A polar vortex is a relentless, massive cyclone around the north or south poles. It rarely spreads densely populated areas. The centers of these cyclones are low-pressure zones which are surrounded by high-pressure zones at the polar.

- The core strengthens during winters and summers are weaker. This happens basically due to presence of high temperature systems in the west or east Pacific during summers, displacing cold air from poles, making them weak.

- Wind blows at a speed of 100mph, trapping the cold air in the Arctic. However on splitting, it is capable of flinging the cold air far off. The polar vortex at Arctic is weaker than Antarctica due to the distribution of land mass in the former that gives rise to Rossby waves, causing a breakdown of vortex.

- This leads to an exchange of winds between the poles and high pressure regions of of the mid latitude. Meanwhile the vortex remains undisturbed in the Antarctica.

- The low temperatures during winter in the South Pole forms extremely tiny ice particles which then form polar stratospheric clouds. These clouds can only form at temperatures below -80º C and Antarctic polar vortex provides ideal conditions. The number of chlorine-bonded molecules merge with the ice particles wherein there is a release of chlorine.

- Sunlight during summers, through UV rays breaks the chlorine molecules into radicals which results into ozone depletion. Due to greater air exchange in North Pole, the impact is much less, of this similar phenomenon which is observed in the Arctic as well.

- This is why the occurrence of seasonal reduction in Ozone is better known as "Ozone Hole" in Antarctic and "Ozone Dent" in Arctic.