Chapter 4. The emissions gap - Emissions Gap Report 2021: The Heat Is On – A World of Climate Promises Not Yet Delivered

The emissions gap is estimated as the difference between projected global GHG emissions assuming full implementation of the mitigation pledges that countries have made for 2030, and emissions under least-cost pathways consistent with the Paris Agreement long-term goal of limiting global average temperature increase to well-below 2oC and pursing efforts to limiting it to 1.5oC, compared with pre-industrial levels. This year, the update of the emissions gap is particularly interesting as it is the first time countries have submitted new or updated NDCs as part of the five-year ambition-raising cycle of the Paris Agreement. Thus, the update of the emissions gap provides an indication of the extent to which the NDC process under the Paris Agreement is working and the progress made. To estimate the emissions gap, updated scenarios that underlie the quantification of the emissions gap are assessed (section 4.2). This year, the mitigation pledge scenarios include the latest available NDCs as well as announced mitigation pledges for 2030 with a cut-off date of 30 August. Further, scenarios consider the repercussions of the COVID-19 pandemic outbreak and possible economic recovery paths. The emissions gap assessment for 2030 is presented in section 4.3, and the implications of failing to bridge the emissions gap for global temperature rise are discussed in section 4.4. In this context, the key questions assessed in this chapter are: What is our current best estimate of the emissions gap for 2030 taking into account the new or updated NDCs, announced pledges and the impact of the COVID-19 pandemic and associated recovery measures? What are the global warming implications over the course of the century?