For more than two decades, the 1987 Montreal Protocol has served as a shining example of how to get things done on the environment in the international arena. By banding countries together to preserve Earth’s shield against harmful ultraviolet rays, the agreement has already eliminated many ozone-depleting substances and should see off most of the rest by 2030. And in doing so, it has done more to reduce greenhouse-gas emissions than the 1997 Kyoto Protocol, which was signed expressly for that purpose. It is equally clear that Montreal could do more on the climate front — if a handful of countries would simply put politics and turf battles aside.

The Montreal Protocol itself has become a bargaining chip in the climate negotiations.

The next opportunity for progress will come when ozone negotiators gather later this month for their annual meeting in Bali, Indonesia. On the agenda again are proposals to regulate a potent and increasingly important class of greenhouse gases known as hydro-fluorocarbons (HFCs), and once again China, India and, to a lesser extent, Brazil are expected to block any real action. It would seem that the best outcome would be a strong vote on yet another non-binding resolution to consider the issue again next year. In this sense, little seems to have changed since the summer of 2009, when Nature first recommended that Montreal delegates accept this new challenge (see But there is still reason for hope.

The official line on why obstructing countries at the Bali meeting will oppose HFC regulation under Montreal is bureaucratically flawless: HFCs do not destroy ozone and so are the responsibility of parallel climate negotiations, which will reopen in Durban, South Africa, a week later. Opposing countries also fear a precedent-setting shift of climate regulations out of the Kyoto Protocol — a treaty that developing countries support because it puts the onus on industrialized nations — and into a framework in which action is mandatory for everybody. The Montreal Protocol itself has become a bargaining chip in the climate negotiations.

This is unfortunate, as the logic for tackling HFCs under the Montreal Protocol is powerful indeed. After all, the gases were introduced to replace the ozone-eating compounds outlawed by the treaty. And they could be regulated using the same tools that have helped the agreement to promote an orderly transition to less damaging chemicals. Moreover, because HFCs can be thousands of times more effective at trapping heat than carbon dioxide, they unbalance the carbon markets on which Kyoto relies. (The most notorious example, HFC-23, is a waste product of the production of Teflon and other materials. Some companies in India and China make more money from destroying HFC-23 under the Kyoto Protocol’s Clean Development Mechanism than they do from selling chemicals.)

In effect, industrialized countries are paying way over the odds to destroy HFCs. Recognizing this, the European Commission has already moved to ban any new HFC-23-destruction projects from its carbon trading scheme.

By contrast, under Montreal Protocol rules, industrialized countries would lead the development of alternative chemicals and phase out the most potent greenhouse gases, while putting money on the table to help developing countries follow suit. It is a fair system based on actual costs, and it works.

The Federated States of Micronesia first proposed targeting HFCs under the Montreal Protocol as part of a simple climate agenda that could be advanced quickly while the world deliberates over the harder problem of carbon dioxide. The United States, Mexico and Canada joined the cause, eventually followed by the European Union. By 2009, some 41 countries had offered their support for the idea. That number increased to 91 countries in 2010, and it could go even higher this year.

Montreal will celebrate its twenty-fifth anniversary in 2012, and a fitting way to honour its accomplishments would be to expand its mission. Momentum continues to build, leaving China, India and Brazil increasingly isolated on this issue. Each of these nations has been critical of industrialized countries for not doing enough to curb greenhouse-gas emissions, and rightly so. But in this case, they have only themselves to blame.