The impact of policy and model uncertainties on emissions projections of the Paris Agreement pledges
File(s)
Published version
Author(s)
Type
Journal Article
Abstract
Tracking progress towards the Paris Agreement climate goal requires understanding the 2030 emission levels implied by countries' National Determined Contributions (NDCs). However, key uncertainties and assumptions impact greenhouse gas (GHG) emission projections implied by the NDCs. This study analyses this impact, both globally and for major emitting countries. We find that the assessed uncertainties markedly affect global GHG emission projections. Full achievement of NDC targets is estimated to result in a range of 46–60 GtCO2eq by 2030 (median estimate: 53 GtCO2eq). The uncertainty in measuring historical emissions, including land-use, as reflected by different datasets is the most important contributing factor. This is followed by two equally important factors globally: socio-economic baseline uncertainty and uncertainty about the emissions implied by current policies in case NDCs are less ambitious than these. Overall, the impact of policy uncertainty (i.e. uncertainty resulting from conditionality of or ranges in NDC targets and uncertainty in emissions resulting from current policies) is about equally important as model/technical uncertainty (i.e. uncertainty in historical emissions and socio-economic baseline variations). This new insight is important for decision makers and researchers because a larger share of the total uncertainty is now attributable to aspects that can be influenced by policy decisions compared to previous analyses of NDC uncertainty.
Date Issued
2023-05-01
Date Acceptance
2023-04-20
Citation
Environmental Research Letters, 2023, 18 (5)
ISSN
1748-9326
Publisher
IOP Publishing
Journal / Book Title
Environmental Research Letters
Volume
18
Issue
5
Copyright Statement
© 2023 The Author(s). Published by IOP Publishing Ltd Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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https://www.webofscience.com/api/gateway?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000981787300001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=a2bf6146997ec60c407a63945d4e92bb
Subjects
CLIMATE
climate change mitigation
climate policy
COUNTRIES
Environmental Sciences
Environmental Sciences & Ecology
integrated assessment models
Life Sciences & Biomedicine
Meteorology & Atmospheric Sciences
NDC
NEED
Paris Agreement
Physical Sciences
Science & Technology
TIME
uncertainty
Publication Status
Published
Article Number
054026
Date Publish Online
2023-05-05