New CFCs and HCFCs were detected in samplings from Greenland snow and from relatively unpolluted air in Tasmania. Samplings date from 1978 and 2012. All indicate that the four new gases are of recent release and have been accumulating.
Why is it of concern? After all it is only 74,000 tons when compared to the more than one million tons per year humans used to produce back in the latter part of the 20th century. The gases which were invented in the 1920s are composed of carbon, chlorine and fluorine. In combination these slowly degrade. As a result they have the time to rise into the stratosphere where the chlorine component contributes to ozone destruction. When compared to natural occurring chlorine the CFCs and HCFCs are far more destructive. That’s because chlorine on its own degrades much faster and because of its high specific gravity never reaches into the stratosphere.
CFCs and HCFCs were banned completely as of 2010 based on an international signed agreements dating back to 1989. But the gases have a nasty habit of hanging around from between 20 and 120 years before the ultraviolet rays emitted by the Sun deplete them. That’s the problem because the gases have plenty of time to mix in the lower atmosphere and rise into the stratosphere where they do their damage. Without the protective ozone layer those ultraviolet rays get through and contribute to rates of occurrence of cancer and cataracts.
And one more thing. Ozone depletion may also be contributing to the acidification of the Earth’s oceans. So additional emissions have many consequences.
Currently ozone has been disappearing from the upper atmosphere at the rate of 4% per decade for the last 30 years. That is happening despite the ban on CFCs and HCFCs. That’s because of the longevity of the gases already released. These new human created suspects may turn out to be producers of insecticides and solvents. The search is on to find out who are the culprits. We may never know.
The actual numbers:
For climate change skeptics the Antarctic statistics support their belief that global warming is nonsense while Arctic results give global warming champions the smoking gun evidence that something needs to be done by all of us.
Sorry to disappoint the skeptics but geography plays a key role in the differing results at the two poles. The Arctic is far more susceptible to global warming than the Antarctic because the Arctic is a sea surrounded by land whereas the Antarctic is an isolated continent surrounded by sea. These two opposite features play a significant role in why one has shrinking ice while the other continues to see the growth in sea ice. Air currents and ocean currents are very different at our two poles. Warming continents impact the Arctic raising surface temperatures and the air above. As summer sea ice melts more ocean is exposed absorbing heat rather than reflecting it back into space. As a result the Arctic is experiencing the global heating effect much more than its polar opposite.
The Antarctic has been an isolated continent at the southern pole for 30 million years. Surrounded by cold ocean currents, uninfluenced by the warming of other land masses in its isolated state, and battered by unimpeded sea winds, it is a natural refrigerator that reinforces the cooling of the ocean surfaces that surround it. The ozone hole over the Antarctic may be contributing to this cooling as well affecting ultraviolet light absorption which in turn impacts atmospheric circulation contributing to cooling over the southern pole.
So while the thermometer rises over most of the continents and oceans of the planet the Antarctic, in isolation, remains in a deep freeze. Scientists, however, project that this lag by the Antarctic will come to an end before the close of the 21st century if we continue to see the Earth continue to heat up.
