A fragile atmosphere. Photo credit: NASA
For the first time, dramatic ozone loss over the Arctic has formed a “hole” in the ozone layer to rival that above the Antarctic, a paper in the science journal Nature revealed on Sunday. We’re used to hearing of the annual removal of much of the Antarctic ozone forming an ozone hole, but this is the first year that there is evidence of the pattern being replicated so dramatically at the Northern pole of the planet. Over 80 percent of the ozone above the Arctic was destroyed at an altitude of roughly 20 kilometres, with the hole growing to cover an area of roughly 2 million square kilometres.
Holes in the ozone layer typically coincide with low temperatures, but the authors claim that this finding reveals the Arctic ozone’s susceptibility to damage at milder temperatures than those in the Antarctic. Since the emergence of the Antarctic ozone hole in the 1980s, much has been done to prevent further chemical damage being done by humans to the protective layer, but many may fear that this is an ominous finding that spells danger for the planet and, more importantly, the people living on it. But is this a human driven development, and are we in any real danger?
Blame the weather. Although recent temperatures in the Arctic have not been dramatically low, it has been cold for longer. Wired report that Michelle Santee, one of the paper’s authors, said “it was continuously cold from December through April, and that has never happened before in the Arctic in the instrumental record.” Depletion occurs when chemicals that damage the ozone become particularly active, as they do at low temperatures. In addition to the cold, the BBC reports that strong winds may have compounded the problem: “the polar vortex was stronger than usual. Here, winds circulate around the edge of the Arctic region, somewhat isolating it from the main world weather systems.” The use of ozone-destroying compounds such as chlorofluorocarbons (CFCs) has been greatly reduced since legislation in place since 1987, but these substances “persist for decades in the upper atmosphere”, meaning they still linger on and cause these problems today.
People at risk? The Daily Mail warns that “Europe, Canada and Russia [are] at risk”, but Bruce Armstrong, speaking to The New Scientist, was more reassuring: “Occasional ozone depletion episodes such as this would add very little to the underlying population’s risk of UV-related cancer.”
It’s all our fault. Climate change may have played a role in this problem, as, paradoxically, global warming cools the stratosphere while warming the surface, and if climate change is going to continue to cause lower temperatures in the stratosphere, it could delay the closing of the ozone holes. That said, it’s not time to panic just yet. Paul Fraser told ABC News that scientists were unsurprised by this finding, and confirmed that he still expects the ozone holes to close up with time, as the damaging chemicals in the atmosphere deplete. Phew.
More science
- Can things travel faster than light?
- Tatooine found
- Space junk reaches tipping point
- Space is full of our junk
- Websurfing refreshes workers
