Is the ozone hole getting bigger? Is the banning of CFCs enough to stop it?
1 Answer
It continues to fluctuate normally. The apparent effect of the Montreal Protocols to ban CFCs was to stop the decrease, and possibly allow replenishment by natural phenomena.
Explanation:
Keep in mind that the actual amounts (concentrations) of ozone are very small, although important. The normal fluctuations at any mean (average) level are also large enough that it is difficult to determine exactly what a "normal" or especially 'optimal' level of stratospheric ozone is.
The image below shows the Antarctic ozone hole on September 13, 2014, as observed by the Ozone Monitoring Instrument (OMI) on the Aura satellite.
Earth’s protective ozone layer is on track for recovery within the next few decades according to a new assessment by 282 scientists from 36 countries. The abundance of most ozone-depleting substances in the atmosphere has dropped since the last assessment in 2010, and stratospheric ozone depletion has leveled off and is showing some signs of recovery.
These observations were the headlines of the recent “Assessment for Decision-Makers,” part of a larger report to be released in early 2015 by the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO).
