Lessons from the Montreal Protocol

Michael J. Pieropan

Michael J. Pieropan

ENVS 02: Human Nature, Technology and the Environment

Professor Everbach

Essay 4: Industrialization and the Environment

April 8, 2006


As a child, I can vividly remember the urgent public warnings of inevitable ozone depletion and its detrimental effects on global warming. At the time, very little was known about the causes or overall effects of ozone depletion. The scientific uncertainty may have added to the public hysteria, as many citizens became frantic over the idea of an ever-increasing stratospheric hole above Antarctica.

A decade later, much of the panic and global danger has subsided. The establishment of the 1987 Montreal Protocol on Substances that Deplete the Ozone Layer, and subsequent Amendments and Adjustments, has significantly curtailed the deterioration of the ozone layer. Assuming continued compliance with the stipulations of the amended Protocol by all nations, it is now estimated that the hole above Antarctica will completely disappear by the middle of the 21st century (Scientific Assessment 18). The drastic turnaround in regards to the ozone layer is an ideal example of the tremendous improvements in environmental quality that can be accomplished with global regulation and support. With the variety of pertinent environmental issues currently threatening our modern world, the rapid upgrade of the ozone layer should stand as model for global cooperation.

In 1985, it was discovered that a hole of substantial size develops annually over the Antarctic from late winter through early spring. Stratospheric ozone concentrations display a cyclical pattern; ozone-rich air is transported from the tropics to the poles during the winter and spring, while uninterrupted sunlight during the summer months ignites a reaction that results in ozone destruction. “Ozone is produced via solar ultraviolet photolysis of oxygen and destroyed through catalytic cycles involving reactive nitrogen (NOy), halogen (chlorine and bromine), and hydrogen species (HOx) (Fahey 1).” Both NOy and HOx are naturally produced in the atmosphere, and their relative concentrations have not been significantly increased by human activities. However, the abundance of halogen species in the stratosphere is largely attributable to the actions of human beings. Chlorofluorocarbons (CFCs) and other ozone-destroying halocarbons release a substantial amount of chlorine and bromine into the atmosphere. Scientific analysis has concluded that the presence of such halogen content in the stratosphere is responsible for the observed hole over the Antarctic.

One of the main stipulations of the Montreal Protocol required substantial reductions in the production of these destructive halogens, particularly by developing countries (who are often characterized by heavy industrialization and substantial emissions of pollutants). In 1999, an Amendment was added that restricted that production or consumption of known ozone-depleting compounds (primarily the CFCs) by all Parties to the Montreal Protocol. A Scientific Assessment of Ozone Depletion, conducted in 2002, concluded that stratospheric concentrations of ozone-depleting substances are currently at or near a peak. Total stratospheric amounts of chlorine and bromine, which have grown steadily for decades, have plateaued in the past few years. Simulation models suggest that minimum column ozone levels will be reached prior to 2010 (if it hasn’t been reached already).  The expected decline of halogens will lead to considerable increases in the abundance of global ozone. A recovery to pre-1980’s levels of stratospheric ozone, which includes the complete elimination of the Antarctic hole, is expected to be reached by the middle of this century (Scientific Assessment 2-10).

A decade ago, the issues of ozone deterioration and global warming threatened contemporary ways of living and created a sweeping social panic. It is highly unlikely that citizens of the time would have given legitimacy to the optimistic claim that ozone deterioration would basically be eliminated in a mere 10 years. Astoundingly, that is exactly what has happened. The Montreal Protocol restricted the production and consumption of ozone deteriorating substances, and was adhered to by a majority of nations in the world. Parties to the Montreal Protocol included both developed countries as well as developing and 3rd world nations.

Adherence to the Montreal Protocol represents an ideal example of the power of global cooperation. The countries of the world united for a common good, and were able to achieve tremendous improvements in a very short time. The key to the success of the Montreal Protocol was the strict nature of the regulations imposed, and the fact that it was adopted by an overwhelming majority of countries. Its overwhelming success in rapidly improving ozone depletion shows the overwhelming force of global collaboration towards a mutual end. Given the number of threatening environmental issues in today’s world, the triumph achieved by the Montreal Protocol should stand as a blueprint for addressing impending environmental deterioration. To achieve significant results, a regulation must be stringent and require adherence by all countries of the world. Rather than allowing countries to set individual domestic environmental policies, global regulation is necessary to handle dire issues. While developing countries may claim that universal regulations put them at an economic disadvantage, those very same developing countries are responsible for a considerable percentage of pollutant emissions. The success of the Montreal Protocol provides testament to the fact that global cooperation and adherence to a universal regulation is necessary to achieve significant environmental improvement.



Fahey, D.W. and A.R. Ravishankara. “Enhanced: Summer in the Stratosphere.” Science Magazine. March 19, 2003.

Kerr, Richard A. “A Brighter Outlook for Good Ozone.” Science Magazine. Vol. 297. September 6, 2002. Pgs. 1623-1625.

Scientific Assessment Panel of the Montreal Protocol on Substances that Deplete the Ozone Layer. “Scientific Assessment of Ozone Depletion: 2002.” Executive Summary. July 31, 2002.

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