An Overview of International Climate Change Law, including the Paris Agreement

At the core of international climate change law is the 1992 UN Framework Convention on Climate Change (UNFCCC) and its several follow-on instruments, including, most recently, the 2015 Paris Agreement. These agreements and the decisions taken thereunder address a wide range of issues, including mitigation, adaptation, reporting, capacity-building, and financial assistance, among many others. The Convention and its progeny (UNFCCC regime) are undoubtedly the primary focus of global climate efforts. At the same time, the UNFCCC regime is only part of an international " regime complex" that includes other institutions, such as the Green Climate Fund, and other instruments, such as the International Civil Aviation Organization's 2016 Resolution on a global market-based measure to address international aviation emissions and the Montreal Protocol's 2016 Kigali Amendment on the production and consumption of hydrofluorocarbons. At this point, concern about climate change is so pervasive that it is the rare international arena that is not affected; even the Universal Postal Union has taken up the issue. This article focuses on the UNFCCC regime. There are many possible ways to examine it. One could start from the present, from the Paris Agreement in particular, and trace the derivation of various elements. One could look at it thematically, focusing on adaptation, mitigation, finance, and other aspects. This article looks at the regime historically, from the 1992 Framework Convention to the 2015 Paris Agreement, highlighting four issues and how they have been addressed over the years. In the case of two of these issues - legal character and the balance between nationally determined and internationally determined elements - it concludes that the Paris Agreement reflects a "Goldilocks" approach between past extremes. In the case of the other two differentiation among Parties' commitments and environmental ambition Paris represents a distinct advance over previous instruments.