The IPCC estimates the costs of adaptation to be between 70-100 billion per year (Chambwera, et al, 2014). However, the UNEP Adaptation Gap Report 2015 (UNEP, 2016) estimates that the costs of adaptation are likely to be two-to-three times higher than current global estimates of adaptation costs by 2030, and potentially four-to-five times higher than current estimates by 2050. The Paris Agreement notes that the scale of the adaptation challenge and its associated costs are linked to progress on mitigation, i.e. less progress on mitigation will increase the need for and the costs of adaptation, while more mitigation will reduce the need to adapt and make adaptation less costly (article 7.4).