The Earth’s protective ozone layer has been slowly recovering since 1987, when harmful gases once used in pesticides, hairsprays and refrigerants were banned, but new samples of these gases are now being found in the air and ice once again. Scientists are busy trying to figure out how these new additions to the atmosphere got there, since such gases should have been phased out of all products in the years following the Montreal Protocol treaty’s adoption in 1987.
The ozone layer of Earth’s atmosphere filters out UV rays, cosmic radiation and other harmful effects, allowing many species to survive on the planet without more outbreaks of skin cancer, cataracts and other illnesses. The UN, alerted by studies from various scientists, put a 1989 moratorium on the use of chlorofluorocarbons (CFCs) in any form, to be enforced completely by the year 2010. This treaty was agreed upon in order to save the denizens of Earth from the effects of such radiation if the hole in the protective layer were to get any larger. Another culprit, hydrochlorofluorocarbon (HCFC), was to be eliminated by 2030.
These two types of gases come in many forms, but all have similar degrading effects on Earth’s atmosphere. The former was used in many configurations from the 1950s through the 1980s, while the latter type was developed later on as an alternative to CFCs. HCFCs are somewhat less damaging to the ozone layer, but are on track to be eliminated by the ban as well, since they contribute significantly to the problem.
The new gases, unfortunately, seem to include three types of CFCs as well as one new type of HCFC, meaning that at least three of them ought not to exist. Found in the ice over Greenland, they have been found to be completely new forms of the banned gases, and thus cannot be left over from previous emissions. Having been banned in 1987 and eliminated by 2010, these gases ought not to have been found in the atmosphere or damaging the ozone layer four years after they purportedly ceased to be produced anywhere on Earth.
A comparison with gas levels in Tasmania, which is notoriously low in pollution, shows the character of the gases, as well as their levels. Scientists estimate that approximately 74,000 metric tons of the material may have been released. Cores taken from the ice in Greenland indicate that these dangerous gases are definitely artificial in that they did not exist before 1960.
The scientists involved in the study have said that the amount of CFCs and HCFCs released thus far has not been enough to cause irreparable damage because the new levels are minuscule compared to what was released before the 1990s. The team, comprised of scientists from many countries, including the UK, Germany, the Netherlands, Switzerland, France and Australia, published their findings in Natural Geoscience.
Since the new concentrations of gases had to come from somewhere, the team posits that they might be produced during manufacturing taking place using some of the few loopholes in the Montreal Protocol. The scientists involved have shared hopes that the discovery will force the UN and its participating countries to remove all exemptions in the treaty. Their concern comes from the fact that this spike in damaging gases is sudden. There had been no similar increases for the period after the Protocol was enacted in 1989.
CFCs, and to some extent the less-damaging HCFCs capture more heat than does carbon dioxide, and are thus more dangerous to global temperature management. If CFCs are kept down, it is hoped that the holes in the ozone layer caused by their mass production will have reverted to their 1950s state by 2080. Scientists hope that the source of the emissions can be located by extrapolating the movements of the gases. Since the gases were found first in Greenland and only detected later in Tasmania, it is likely they were originally dispersed in the northern hemisphere. A study of air currents might lead to the culprit.
CFCs were thought to have been under control for years now. While the source of these dangerous gases is being pursued by scientists, U.N. representatives must comb over the Montreal Protocol in order to figure out what loopholes allowed these new gases, banned since 1987, to be produced to continue to damage Earth’s ozone layer.
By Kat Turner