Analysis of the Success of the Vienna Convention for the Protection of the Ozone Layer and the Montreal Protocol

Marjorie Mygrants, Vol. 36 Associate Editor

The Vienna Convention for the Protection of the Ozone Layer and the Montreal Protocol on Substances that Deplete the Ozone Layer are perhaps the most successful international treaties the world has seen.  In fact, both of the agreements are the most widely ratified treaties in United Nations history.[1]  This fact alone has helped lead to much of the treaties’ success, especially since worldwide recognition of a problem and willingness to take specific action to address the problem is a process that is necessary for a significant impact to occur in resolving the issue.  Of course, this is the goal of any treaty.  But, the reality is that most treaties are lacking in some criteria – enforcement, breadth of state ratification, and/or compliance with terms of the treaty.  This article will address the aspects that have made the treaty so successful.

The Vienna Convention provided the general framework for the tools to protect the ozone layer that surrounds the globe.  Generally, “The objectives of the Convention were for Parties to promote cooperation by means of systematic observations, research and information exchange on the effects of human activities on the ozone layer and to adopt legislative or administrative measures against activities likely to have adverse effects on the ozone layer.”[2]  Scientists first published their hypothesis that man-made chemicals could harm the stratospheric ozone layer in 1974.[3]  The ozone layer is important in keeping out harmful ultraviolet radiation from the sun.[4]  Losing this protective layer would cause serious problems to humans, plants, and animals alike.  The damaging radiation could not only cause mutations in any of the human, plant, or animal cells, but it would also cause increases in skin cancer and other serious health issues.[5]  “The scientists found that the chlorofluorocarbon gases (CFCs), which were widely used and viewed as posing no harm, could migrate to the stratosphere, remain intact for decades to centuries, and by releasing chlorine, break down the ozone layer.”[6]

The Montreal Protocol went into effect in 1989.  The purpose of the Protocol was to provide a system of backing the framework that was established in the Vienna Convention, in order to further the environmental goals and address the concerns that were established.  “The ozone agreements are remarkable, in that they are the first to address a long-term problem in which the cause of the damage occurs today, but the effects are not evident for decades hence… Since scientific understanding of the problem would change, the agreements needed to be flexible and capable of being adapted to accommodate new scientific assessments. No single country or group of countries could address the problem of ozone depletion alone, so maximum international cooperation was needed.”[7]  In doing so, the Montreal Protocol had to address the interests of a number of different groups, which usually has the effect of plaguing further progress in many treaties.[8]  The treaty controls the consumption and production of certain non-natural chemicals, and also sets out a timeframe for reduction targets for these chemicals for each of the ratifying states to abide by.[9]  Without the Montreal Protocol, it is estimated that the ozone depletion would have been 10 times worse than current depletion (in 2012) by 2050.[10]  The Protocol is estimated to have prevented 19 million more cases of non-melanoma cancer, 1.5 million more cases of melanoma cancer, and 130 million more cases of eye cataracts.[11]  Furthermore, 98 percent of the ozone depleting substances controlled by the Montreal Protocol have been phased out, and that because of the implementation of the treaty and its provisions, the ozone layer is estimated to return to pre-1980 levels by 2050 to 2075.[12]  Because these chemicals are also greenhouse gases, this treaty has had a mitigating effect on climate change.[13]

It is clear that the treaties have been a success in several ways, from their implementation and enforcement to the clear positive and lasting effects they have had on the quality of the ozone layer as well as the health of living things on this planet.  The Vienna Convention and the Montreal Protocol challenge the commonly held notion that treaties are not effective in international law and that state driven mechanisms are outdated.

Science, of course, plays a large role in these treaties.  The Montreal Protocol addresses specific chemicals.  Money had driven the use of these chemicals, and it would not be easy to convince countries, whose economies were boosted by the consumption and trading of these products, to stop their production.  Science needed to be a tool to convince the countries.  Science is also ever-changing and the Protocol reflected the need to incorporate new scientific advances over time.  “Anticipating changes in scientific knowledge about the ozone layer and emergence of new problems in implementing the Protocol, negotiators included several provisions to provide flexibility.”[14]

Additionally, the Montreal Protocol addressed developing countries in unique ways and has special provisions relating to them.  By creating different provisions, it eased the burdens on those countries and incentivized them to participate meaningfully in the treaty.  This also helped attract countries that would not otherwise have participated in the treaty.[15]  For example, “Article V gives qualifying developing countries a ten year delay in complying with targets and timetables, a separate consumption limit of 0.3 kilogram per capita, and access to the Montreal Protocol Fund to assist with compliance costs.”[16]  Inevitably, some countries would gain tremendously with the treaty while others would not (mainly, the poor countries).  So, funds were created by the more industrialized countries who were reaping many of the benefits of the treaty in order to support the poorer countries who were not able to bear the cost of participating in the treaty.[17]

Just as it was necessary to create special provisions for developing countries in terms of leniency, it was equally important to create punishment provisions for free-riding states.  This problem is exacerbated when dealing with public goods or common-pool resources because they are universally accessible.[18] The problem with free riding occurs when there is a public good involved, like clean air or a healthy ozone layer.[19]  Inevitably, all countries will benefit from the public good, in this case the improvement to the ozone as a result of the states who have ratified the treaties, often times at an expense to industry and the economy of those ratifying parties.  Therefore, each country also has a large incentive to let the other countries make the sacrifices, while still reaping the benefits.[20]

A fundamental aspect of the Montreal Protocol’s success is that it has reversed the incentives to free ride.[21]  Just as poorer countries were rewarded with economic incentives for joining the treaty, there were significant punishments for those who did not join.  “The threat of punishment came in the form of a ban on trade between signatories and nonsignatories in substances (such as CFCs) controlled by the treaty. It also bans imports of products (such as refrigerators and air-conditioning units) containing these substances. And it leaves open the possibility that signatories may ban the import of products made with these substances, such as computer circuits cleaned with CFCs.”[22]  This essentially cut out the source of the fear that stopped some countries from signing, so they no longer had that excuse not to sign.  Their worry was that if they took (often expensive) action towards reducing their CFCs, and that other non-signers continued to use CFCs in their products rather than switching to the more expensive alternatives, then those countries would get the benefit of the better ozone health while also not incurring the expense of changing.[23]  In addition, the point was to get manufacturers in all countries thinking about solutions and alternatives to CFCs, and thereby create a new market for these alternatives.  If every country was bound to not use CFCs, then there would be a greater incentive on each country to develop alternatives, and thereby create a new market for non-ozone depleting substances.[24]

Monetary incentives also attached to fulfillment of the treaty’s environmental objectives.  The United States was the world’s biggest consumer and producer of CFCs.[25]  For the US, the costs of implementing the Montreal Protocol were relatively low in comparison to the gains in terms of lives saved; this boiled down into an investment.[26]  “The EPA calculated that implementing the Montreal Protocol would prevent 245 million cancers, including more than 5 million cancer deaths, by 2165. Value a life at US$3 million and the benefits quickly add up.”[27]  So, for some of the biggest producers and consumer of CFCs, like the United States, there were the monetary incentives to help drive this consumption and production down (which ultimately cost money too).  The benefit of saved money help to outweigh some of the cost.[28]  Additionally, these are some of the gains that allowed the big countries, like the US, to afford to set up the fund that allowed the developing nations to participate, which in turn helped everyone.[29]

Finally, the self-enforcing nature of the Protocol has been essential to its success.  “In other words, it must be in the interest of every signatory to stick to the rules. If a treaty does not give countries an incentive to do that, no world government will do the job instead. States are sovereign and will act principally in what they perceive to be the self-interest of their citizens.”[30]  Without it being self-enforcing, a treaty lacks any real ability to make progress.

[1] UNEP News Centre. South Sudan Joins Montreal Protocol and Commits to Phasing Out Ozone-Damaging Substances, United Nations Environment Programme (Jan. 23, 2012),

[2] Ozone Secretariat, The Vienna Convention for the Protection of the Ozone Layer, United Nations Environment Programme (2010-2011),

[3] Edith Brown Weiss, Introductory Note, Audiovisual Library of International Law,

[4] Id.

[5] Id.

[6] Id.

[7] Id.

[8] Id.  (“The Montreal Protocol reflects a convergence of interest of scientists who warned of growing threats to the ozone layer, private industry that wanted a level playing field as companies responded to new national legislation controlling the harmful chemicals, nongovernmental organizations advocating environmental protection, and national governments that increasingly saw an international agreement as in their own best interests.”)

[9] Id.  (“CFCs, halons, fully Halogenated CFCs (HCFCs), methyl bromide, and similar chemicals.”)

[10] South Sudan Joins Montreal Protocol and Commits to Phasing Out Ozone-Damaging Substances, supra note 1  (“It is estimated that without the Protocol, by the year 2050 ozone depletion would have risen to at least 50% in the northern hemisphere’s mid latitudes and 70% in the southern mid latitudes.”)

[11] Id.

[12] Id.

[13] Weiss, supra note 3.

[14] Id.

[15] Id.  For example, “Article 2(6) was intended to attract countries such as the former Soviet Union to join the Protocol, in that it lets a country add facilities under construction or contracted for prior to September 1987 to its base level for calculating its compliance with base year production.”

[16] Id.

[17] Frances Cairncross, What Makes Environmental Treaties Work?, Conservation, July 29, 2008, (“In its early days, Montreal assumed that all industrialized countries did equally well abiding by the treaty. But, as developing countries began to sign up and once the Berlin Wall came down, that was no longer the case. Luckily, the overall gains to some countries were so great that they could afford to set up a special fund from which to pay developing and ex-communist countries some of the costs of participating. Over US$1 billion has been contributed to this fund by rich countries—a small fraction of the benefit these countries would gain from the investment. By making everyone a winner, Montreal’s negotiators ensured that it was a success.”).

[18] See,

[19] Cairncross, supra note 17.

[20] Id.

[21] Id.

[22] Id.

[23] Id.

[24] Id.

[25] Id.

[26] Id.  (“These huge gains came largely from eradicating the big health risk that ozone depletion entails.”)

[27] Id.

[28] Id. (”Technical advances meant that the substitutes turned out to be less costly than initially predicted.”)

[29] Id. (“Over US$1 billion has been contributed to this fund by rich countries—a small fraction of the benefit these countries would gain from the investment. By making everyone a winner, Montreal’s negotiators ensured that it was a success.”)

[30] Id.