UN Environmental Report Reveals That The Ozone Layer Is Beginning To Recover

Chuck Bednar for redOrbit.com – Your Universe Online
The ozone layer that protects the planet from harmful ultraviolet radiation is on the road to recovery, scientists from the United Nations Environment Programme (UNEP) and the World Meteorological Organization (WMO) announced on Wednesday.
According to BBC News environmental analyst Roger Harrabin, a new report compiled by an international team of 300 scientists reveals that the ozone layer is starting to show signs of thickening, and the ozone hole that appears annually over Antarctica has stopped growing larger.
The UNEP and WMO said it will take decades before the hole begins to shrink, and credited the progress to “concerted international action against ozone depleting substances.” Without global policies such as the Montreal Protocol, atmospheric levels of ozone-depleting substances could have increased tenfold by 2050, they added.
“International action on the ozone layer is a major environmental success story,” said WMO Secretary-General Michel Jarraud, according to Reuters reporter Tom Miles. He added that the findings of this new report “should encourage us to display the same level of urgency and unity to tackle the even greater challenge of tackling climate change.”
While previous reports have suggested the ozone layer had stopped getting worse, WMO senior scientific officer Geir Braathen told Miles that this is the first time scientists have been able to say “that we see indications of a small increase in total ozone. That means recovery of the ozone layer in terms of total ozone has just started.”
Based on global models, the Montreal Protocol will have prevented two million cases of skin cancer annually through 2030, as well as prevented considerable damage to human eyes and immune systems and protected agriculture and wildlife, UNEP said. Since so many ozone-depleting substances are also potent greenhouse gases, it has had an overall positive impact on the global climate, the report authors explained.
The study found that Montreal Protocol and similar agreements have led to enough decreases in gases such as chlorofluorocarbons (CFCs) and halons that the ozone layer is now expected to recover to 1980 benchmark levels (the period before which there was significant depletion) by the mid-century in most parts of the world. Those benefits, however, could be undone based on the projected emissions by hydrofluorocarbons (HFCs).
While HFCs, which are used to replace those ozone-depleting substances, do not damage the ozone layer directly, many of them are potent greenhouse gases and currently contribute about 0.5 gigatons of CO2-equivalent emissions each year. Those emissions, the study authors said, are growing at a rate of seven percent annually, and left unchecked they “can be expected to contribute very significantly to climate change in the next decades.”
Mexican chemist Mario Molina, who was a co-recipient of the 1995 Nobel Prize in Chemistry for his research into the ozone layer, told Gail Sullivan of the Washington Post that the results were “a victory for diplomacy and for science and for the fact that we were able to work together.”
However, the news was not all good, Sullivan said. One of the ozone-depleting chemicals that should have been phased out by the international protocols, carbon tetrachloride (CCl4), was actually found to have increased over the past decade. This discovery suggests that the substance, which was used in fire extinguishers, as a precursor to refrigerants, and as a cleaning agent, might still being used illegally in some parts of the world.
“We are not supposed to be seeing this at all,” NASA atmospheric scientist Qing Liang said earlier this week. From 2007 through 2012, countries throughout the world reported zero emissions of CCl4, Liang and a team of researchers found that satellites, weather balloons, aircraft, and surface-based sensors found that the average global emissions of carbon tetrachlorides average 39 kilotons per year, or roughly 30-percent pre-treaty levels.
“It is now apparent there are either unidentified industrial leakages, large emissions from contaminated sites, or unknown CCl4 sources,” she added, noting that computer models suggest that the substance is lingering in the atmosphere approximately 40 percent longer than previously believed. Alternatively, the researchers think it could be possible there is something about the physical CCI4 loss process that is still not fully understood.
—–
What If?: Serious Scientific Answers to Absurd Hypothetical Questions by Randall Munroe