11. The polar vortex of high-speed circulating winds occurs above southern New Zealand during the southern hemisphere spring. 12. This warming of stratospheric air can reverse the circulation in the Arctic Polar Vortex from counter-clockwise to clockwise. 13. The lack of sunlight contributes to a decrease in temperature and the polar vortex traps and chills air. 14. Within this polar vortex , over 50 percent of the lower stratospheric ozone is destroyed during the Antarctic spring. 15. The strength and position of the polar vortex shapes the flow pattern in a broad area about it. 16. These conditions occur at lower latitudes only when the core of Arctic air, called the polar vortex , swings south. 17. The polar vortex is not broken down and the wind reversal from westerly to easterly is less extensive ." 18. It was carried by the Polar vortex winds in a circle around the South Pole, returning after two weeks. 19. A polar vortex is a moving cyclone with a low-pressure, cold center where ozone is less likely to be present. 20. The weakening or strengthening of the polar vortex can alter the sea circulation more than a mile beneath the waves.
