The urgent need to address climate change poses a range of complex moral and practical concerns, not least because rising to the challenge will require cooperation among countries that differ greatly in their wealth, the extent of their contributions to the problem, and their vulnerability to environmental and economic shocks. This thesis by publication in the field of climate ethics aims to characterise a range of national responsibilities associated with acting on climate change (Part I), and to identify proposals for (...) fulfilling those responsibilities through fair and feasible institutional arrangements (Part II). I aim not only to address substantive gaps in scholarly understanding of those responsibilities, but also to strengthen the ability of climate ethics to engage meaningfully with climate policy. Chapter 2 addresses the question of whether wealthy countries owe a “climate debt” to poor countries. It finds that even if climate debt (suitably interpreted) may provide a coherent and morally plausible concept, its political value as a discursive frame that can provide a basis for cooperation is limited. Chapter 3 investigates the role that equity may play in negotiations on a long-term climate change agreement. It argues that developed and developing countries may reach a “principled bargain” if both converge on a way of differentiating their responsibilities that places less emphasis on a rigid dichotomy between the two groups and more emphasis on objective criteria relating to their contribution to the problem and capacity to address it. Chapter 4 explores a question largely overlooked in climate ethics, namely whether wealthy countries owe compensation to those who are adversely affected by the climate policies which they enact. I find that enacting countries have responsibilities to compensate both domestic and foreign citizens who would suffer disproportionate losses from the effects of policies. Chapter 5 assesses whether wealthy countries may legitimately adopt unilateral (or “fragmented”) rather than multilaterally coordinated approaches to raising climate finance for developing countries. It finds that coordinated target-setting, effort sharing and oversight arrangements are essential, but that a mix of unilateral and coordinated approaches to raising funds will be necessary for securing legitimacy. In Chapter 6, through addressing the broader question of what should count as official aid, I consider whether wealthy countries may draw on aid budgets to support developing countries’ efforts to address climate change. I find that the current definition of official aid should be retained but supplemented by specified exclusions from eligibility in order to preserve the aid regime’s integrity. Nevertheless, some climate finance may justifiably be counted as aid provided that concerns relating to the diversion of aid funding are addressed. In addressing these research questions, the thesis seeks not only to make original theoretical contributions to climate ethics but also to strengthen broader scholarly understanding of the ways in which ethics and international public policy may inform one another, particularly by highlighting the role of framing considerations (Chapter 2), feasibility considerations (Chapter 3), and the ways in which principles of fairness and legitimacy map onto institutional functions (Chapters 4, 5 and 6). (shrink)