2014-07. The Antarctic ozone hole: An update.

posted Jul 2, 2014, 11:55 AM by Alan Gould

For GSS Ozone chapter 9. Excerpt: In the 30 years since the ozone hole was discovered, our understanding of the polar atmosphere has become much more complete. The worldwide response to the discovery was fast, but the recovery is slow. ...Although anthropogenic CFCs are emitted mostly in the Northern Hemisphere, they are well mixed throughout the troposphere over the course of a couple of years, and air that enters the stratosphere in the tropics carries with it tropospheric levels of CFCs. ...Although the Arctic and Antarctic are similar in some ways, ozone columns below 180 DU, routine in the Antarctic, have never been observed in the Arctic. Chlorine levels are similar in both hemispheres, but winter and spring temperatures in the Antarctic are much colder than in the Arctic. ...The Northern Hemisphere’s large mountain ranges and its broad contrasts between land and sea temperatures result in a weaker polar vortex, warmer temperatures, and stronger Brewer–Dobson circulation. That stronger circulation leads to greater transport of ozone to the Arctic lower stratosphere and naturally higher ozone; year-to-year variability is also greater than in the Southern Hemisphere.... http://scitation.aip.org/content/aip/magazine/physicstoday/article/67/7/10.1063/PT.3.2449. By Anne R. Douglass, Paul A. Newman and Susan Solomon, Physics Today.