Those who are old enough, may recall the fierce political fight over the 1987 Montreal Protocol to phase out ozone-depleting chlorofluorocarbons (CFCs). Scientists as far back as 1978 had discovered a link between CFCs and destruction of the Earth’s protective ozone layer. Well, good news this week from NASA, who has reported that the hole in the stratospheric ozone is smaller than normal this year. This from NASA,
The ozone hole that forms each year in the stratosphere over Antarctica was slightly smaller in 2013 than average in recent decades, according to NASA satellite data.
The ozone hole is a seasonal phenomenon that starts to form during the Antarctic spring (August and September). The September-October 2013 average size of the hole was 8.1 million square miles (21 million square kilometers). For comparison, the average size measured since the mid-1990s when the annual maximum size stopped growing is 8.7 million square miles (22.5 million square kilometers). However, the size of the hole in any particular year is not enough information for scientists to determine whether a healing of the hole has begun.
“There was a lot of Antarctic ozone depletion in 2013, but because of above average temperatures in the Antarctic lower stratosphere, the ozone hole was a bit below average compared to ozone holes observed since 1990,” said Paul Newman, an atmospheric scientist and ozone expert at NASA’s Goddard Space Flight Center in Greenbelt, Md.
The ozone hole forms when the sun begins rising again after several months of winter darkness. Polar-circling winds keep cold air trapped above the continent, and sunlight-sparked reactions involving ice clouds and chlorine from manmade chemicals begin eating away at the ozone. Most years, the conditions for ozone depletion ease before early December when the seasonal hole closes.
Levels of most ozone-depleting chemicals in the atmosphere have gradually declined as the result of the 1987 Montreal Protocol, an international treaty to protect the ozone layer by phasing out production of ozone-depleting chemicals. As a result, the size of the hole has stabilized, with variation from year to year driven by changing meteorological conditions. [Full article here.]
Despite significant opposition to the Protocol by many within his cabinet, Ronald Reagan decided to support the controversial international treaty. It turns out the scientists were correct, and so was the President. An interesting history of Reagan’s decision and the tumultuous in-fighting within his cabinet at the time can be found here. A comprehensive history, with links to scientific, policy, and media sources, provided by UNEP, can also be found here. Reflecting back almost a quarter-century ago, and laying witness to the environmental success of that momentous decision, there can be little doubt that Reagan made the right one. A difficult one, but the right one. Failure to act then would have surely consigned many to premature deaths, among other harms to natural systems and the economy.
If we are to learn from our past, those who, today, argue that we humans are so insignificant as to be unable to affect earth’s balance, should take note of history.
My problem with this is that we made high impact policy changes after observing this phenomenon for an extremely short period of time. I think I read somewhere that the actual “hole” was first observed in the early 20th century but first measured in the late 1970s. The process seemed very unscientific to me.
Chris, as far as major policy changes go, agree the response was fairly rapid. The CFC and ozone concern was first noted in scientific literature in the mid 1970s. But it wasn’t until the mid 1980s, when the sizable Antarctic hole was observed, that the shift in public opinion and political winds occurred.
When the Montreal Protocol and our subsequent Clean Air act that outlawed CFCs were signed, there was no scientific proof that man-made hair spray and air conditioning coolants caused the Ozone Layer. Almost 40 years later there is better information that shows that HF and HCL compounds source mostly from natural causes such as earthquakes and volcano eruptions – and this will never change. Natural fluctuations in the size of the natural ozone hole do not make trends since measurement techniques questionable and likely inaccurate. However, there are now many rent-seeking scientists and corporations that depend on the government-caused CFC largess now estimated at $200 billion and rising. Why do we think we understand the natural conditions and processes that drive the earth’s climate when man really has no clue beyond faulty measurements and unsubstantiated theory. I think the answer is “follow the money.”
Bob, I don’t disagree with your point on corporate rent-seeking and scientific uncertainty and imperfect science. As Rod Dreher often points out, we should be as skeptical of big business as big government. Notwithstanding, our scientific understanding of these complicated earth processes will never be with absolute certainty. Rather, given their complexities and our incomplete knowledge, the most prudent approach is to respond based on weight of the evidence. There is little credible dispute within the scientific that CFCs are harmful to the ozone layer.