Spring Break
Ozone hole at record size
NASA, UN confirm hole biggest ever
Jacob Stump
Issue date: 10/10/06 Section: Space Technology
- Page 1 of 1
Confirmed by both NASA and the U.N. Weather Agency, the ozone hole over Antarctica has reached a record size. While the numbers vary, between nine million square miles at the low end and 18.3 million square miles at the high end, both agencies agree that the area has surpassed the previous record, which was set back in 2000. Previously, some had suggested that the ozone hole was well on its way to repairing itself.
In 2003 a report was released which said that ozone layer depletion may be slowing down, due to the 1987 Montreal Protocol international treaty, which phased out CFC production completely in 1997. However, CFCs are very versatile molecules; they can survive for 50-100 years before making the trip to the upper atmosphere to absorb UV radiation and break apart, consuming over 10,000 ozone molecules per one CFC.
Therefore while the rate of depletion may be slowing, the ozone layer has yet to begin healing itself. Another contributing factor is the especially cold winter Antarctica has had this year. The cold affects the ozone layer by increasing the amount of depletion. This increase in depletion, though more marked for this year, is part of the normal cycle for the ozone hole.
NASA's Ozone Resource Page (www.nasa.gov/vision/earth/environment/ozone_resource_page.html) says that the ozone hole "opens up" in mid-August, and peaks in September and October. The ozone hole isn't actually a hole, but rather a thinning of the ozone layer over the South Pole.
This allows a significant amount of dangerous UV radiation through the atmosphere that normally would not be able to pass. Luckily there are very few humans in Antarctica for the UV radiation to harm, and the few that are there wear thick layers of insulated clothing. NASA predicts that given proper enforcement of the Montreal Protocol, the ozone hole should show signs of improvement as early as 2018, and actually start to shrink by 2025.
In 2003 a report was released which said that ozone layer depletion may be slowing down, due to the 1987 Montreal Protocol international treaty, which phased out CFC production completely in 1997. However, CFCs are very versatile molecules; they can survive for 50-100 years before making the trip to the upper atmosphere to absorb UV radiation and break apart, consuming over 10,000 ozone molecules per one CFC.
Therefore while the rate of depletion may be slowing, the ozone layer has yet to begin healing itself. Another contributing factor is the especially cold winter Antarctica has had this year. The cold affects the ozone layer by increasing the amount of depletion. This increase in depletion, though more marked for this year, is part of the normal cycle for the ozone hole.
NASA's Ozone Resource Page (www.nasa.gov/vision/earth/environment/ozone_resource_page.html) says that the ozone hole "opens up" in mid-August, and peaks in September and October. The ozone hole isn't actually a hole, but rather a thinning of the ozone layer over the South Pole.
This allows a significant amount of dangerous UV radiation through the atmosphere that normally would not be able to pass. Luckily there are very few humans in Antarctica for the UV radiation to harm, and the few that are there wear thick layers of insulated clothing. NASA predicts that given proper enforcement of the Montreal Protocol, the ozone hole should show signs of improvement as early as 2018, and actually start to shrink by 2025.
Be the first to comment on this story