The Southern Hemispheric ozone hole usually begins to develop in mid- to late August, as the hemisphere emerges from its winter, and peaks in mid-October.
This year it first appeared closer to the end of August and by mid-September was 18.48 million square kilometers in size, smaller than in recent years, including both 2022 and 2023. Though this year’s slow start does not necessarily reflect a recovery of the ozone layer, it does support the notion that expert guidance has made a positive contribution to this vexing problem.
Just a few years after the ozone hole was detected via satellite, the industrialized nations of the world, meeting in Montreal in 1987, adopted what is known as the Montreal Protocol. That international agreement, based upon the consensus scientific understanding of the problem, placed prudent restrictions on the use of chlorofluorocarbons, or CFCs.
The result of this scientifically informed policy-making has been a gradual but systematic healing of the ozone hole. Despite the success of the Montreal Protocol, current estimates are it will require another four decades, if the protocol is followed, before recovery toward pre-ozone hole conditions.
This success should serve as a leading example of the power of scientific analysis and understanding to shape important environmental policy.
The world is facing a slower-burning crisis as a result of human-induced changes to the atmosphere that are, in turn, compelling a change to a warmer climate. There is no lack of scientific consensus of the roots of this problem nor any shortage of science-based prescriptions for seeking its remedy.
The time has long passed for our society to seriously debate, and then begin to take, the bold actions necessary to meet this crisis. Our scientific and industrial infrastructure is more than sufficient to meet this pressing challenge — we have successfully done so before!
Steve Ackerman and Jonathan Martin, professors in the UW-Madison department of atmospheric and oceanic sciences, are guests on WHA radio (970 AM) at noon the last Monday of each month. Send them your questions at stevea@ssec.wisc.edu or jemarti1@wisc.edu.
