It's not science fiction, scientists really have discovered a hole in the ozone layer above the North Pole. Although it is about 40 percent smaller than the one over the South Pole and isn’t nearly as stable, it is still a potentially dangerous development that could affect over 700 million people.
What Have the Scientists Discovered?
In early March, 2011 an announcement from the Alfred Wegener Institute in Germany stated that by the end of winter that the ozone layer over the Arctic Circle had been reduced by fifty percent. NASA confirmed this through measurements made by the Ozone Monitoring Instrument (OMI) on their Aura satellite. What this amounted to was that between the critical altitudes of 11 to 12 miles more than 80 percent of the ozone that was there in January had been destroyed in two short months. According to Michelle Santee, coauthor of the first systematic study of this phenomenon, “the magnitude of the [Arctic] loss is comparable to that in the early Antarctic ozone holes in the mid 1980s.” This is cause for concern. The image to the left shows March 19, 2010, and the same date in 2011.
What Might Have Caused This New Hole?
Scientists believe that the extremely cold winter was the catalyst for the accelerated depletion of ozone around the North Pole. When the stratosphere is cold, chlorofluorocarbons begin to break apart and their free atoms combine with the ozone molecules. The stability of the ozone hole over the South Pole is directly related to the colder stratospheric conditions over the Antarctic land mass, usually -80 C or below. As Paul Newman, an atmospheric scientist and ozone expert at NASA's Goddard Space Flight Center said, “The real question is: Why is this year so dynamically quiet and cold in the stratosphere? That’s a big question with no good answer.”
If we can't figure out why the stratosphere has been so cold we can't do anything from preventing the same conditions from happening every year. The potential dangers of a continual hole in the ozone layer can't be overstated but it would take several years to see the type of damage that would warrant a summer blockbuster.
How is This Impacting the World?
While there is no immediate danger from this temporary hole in the Arctic ozone, if it becomes a permanent structure it could cause serious health problems for up to 700 million residents who live above the 45th parallel north (circle of latitude 45 degrees north of the Earth's equatorial plane) including skin cancer, cataracts and retinal lesions. The hole in the ozone is not a static phenomenon and swirls around the pole as a vortex. There have already been instances where the hole has appeared above heavily populated areas. This is especially disconcerting because the stratospheric ozone layer protects life on Earth from the sun's harmful ultraviolet rays.
Humans wouldn’t be the only life forms affected by a permanent hole in the ozone. Several plants require cyanobacteria to retain nitrogen in their root systems. These bacteria are extremely sensitive to UV rays and their death would result in massive crop loss in several areas of the globe.
In addition to the potentially harmful UV rays if the ozone levels continue deteriorating along the same path as they did at the South Pole global warming is likely to accelerate. Greenhouse gases will trap energy lower down in the atmosphere, heating it up which will in turn reduce the temperature of the stratosphere. As colder temperatures are more suitable for the chemical reactions that break down ozone this would create an amplification effect that would only exacerbate the problem.
Is it Really a Hole?
The hole in the ozone isn't actually a hole in the common sense of the word, it is more of a depression. It also isn't a consistent hole, it is more like a thinning of various layers of ozone at different altitudes. This doesn't mean we should discount it, just that we should understand that thinning is already causing problems and if the entire ozone layer were to vanish we would be left unprotected from deadly UV rays.
We have already done everything we can do to try to prevent this catastrophe from occurring. After the discovery of the hole above the South Pole the 1989 Montreal Protocol limited the production of ozone-depleting substances. If this protocol hadn’t been put into effect when it was the chlorine levels in the atmosphere would already be so high that an Arctic ozone hole would form every spring. Unfortunately the life of chlorofluorocarbons is quite long and it will be decades before the holes at either end of the world begin to close.
- NASA image by Rob Simmon, with data courtesy of Ozone Hole Watch http://earthobservatory.nasa.gov/IOTD/view.php?id=49874
- NASA: NASA Leads Study Of Unprecedented Arctic Ozone Loss http://www.nasa.gov/home/hqnews/2011/oct/HQ_11-329_Arctic_Ozone_Loss.html
- Live Science:Earth's First Arctic Ozone Hole Recorded
- THe Ozone Hole: Arctic Ozone http://www.theozonehole.com/arcticozone.htm
- Science News: Arctic ozone: ‘Hole’ or just not whole?http://www.sciencenews.org/view/generic/id/334917/title/Arctic_ozone_%E2%80%98Hole%E2%80%99_or_just_not_whole%3F