Montreal Protocol & Rio — Quick Rundown

Montreal Protocol (1987)

Treaty to phase out ozone-depleting substances (CFCs, HCFCs, halons). It sits under the Vienna Convention for the Protection of the Ozone Layer (1985), which is the parent framework.

Widely considered the most successful environmental treaty ever — universally ratified, and the ozone layer is actually recovering.

The Kigali Amendment (2016) extended it to phase down HFCs, which are potent greenhouse gases, so it now has major climate co-benefits too.

Rio (1992)

There isn't really a "Rio Protocol." This is the Rio Earth Summit (formally the UN Conference on Environment and Development, UNCED). It didn't produce a single binding protocol; it produced three big things:

• UNFCCC — the climate framework treaty (the parent of Kyoto and Paris)
• Convention on Biological Diversity (CBD)
• Rio Declaration + Agenda 21 — non-binding principles and action plan

So Rio is the origin point of the modern climate regime. Kyoto and Paris are downstream of it.

Are these all COPs?

No — and this is the part worth getting straight.

A COP (Conference of the Parties) is the annual decision-making meeting of a treaty's signatories. It's a meeting, not a document. Each major convention has its own COP series:

• UNFCCC COPs: Paris Agreement was adopted at COP21 (2015), Kyoto Protocol at COP3 (1997).
• CBD has its own COPs.
• The Vienna Convention has COPs, and the Montreal Protocol has its own MOP (Meeting of the Parties) that runs alongside.

So Paris and Kyoto aren't COPs — they're agreements adopted at UNFCCC COPs. Montreal isn't a COP either — it's a protocol with its own MOP. And Rio wasn't a COP; it was the summit that created the conventions whose COPs we now number.

At a glance