An 'equal effort' approach to assessing the North-South climate finance gap

This study employs a number of Integrated Assessment Models to determine what the optimal financial transfers between high-income and developing economies would be if climate mitigation effort, measured as mitigation costs as a share of gross domestic product, were to be divided equally across regions through a global carbon market. We find these to be larger than both current and planned international climate finance flows. Four out of six models imply that a North–South annual financial transfer of around US$400 billion is required by 2050, while the other two models imply larger sums, up to $2 trillion. However, the outlook for multi-country carbon markets is not encouraging at the moment. We thus review some potential sources of funds that might be used to fill the climate finance gap, including public aid, private investment, development banks, and special climate-related facilities. We find the shortcomings of public climate finance appear particularly hard to overcome, and argue that expanding private finance, either in the form of Foreign Direct Investment or through the issuance of ‘green bonds’, appears to be a more promising direction.