Fate of the Atlantic Meridional Overturning Circulation: Strong decline under continued warming and Greenland melting
Yin, J.
- 1Oregon State University
- 2Utrecht University
- 3University of Tokyo
- 4Commonwealth Scientific & Industrial Research Organisation (CSIRO)
- 5National Center Atmospheric Research (NCAR) - USA
- 6University of Arizona
- 7
- 8Environment & Climate Change Canada
- 9Universite Paris Saclay
Journal
Geophysical Research Letters
ISSN
0094-8276
1944-8007
Open Access
bronze
Volume
43
Start page
12252
End page
12260
The most recent Intergovernmental Panel on Climate Change assessment report concludes that the Atlantic Meridional Overturning Circulation (AMOC) could weaken substantially but is very unlikely to collapse in the 21st century. However, the assessment largely neglected Greenland Ice Sheet (GrIS) mass loss, lacked a comprehensive uncertainty analysis, and was limited to the 21st century. Here in a community effort, improved estimates of GrIS mass loss are included in multicentennial projections using eight state-of-the-science climate models, and an AMOC emulator is used to provide a probabilistic uncertainty assessment. We find that GrIS melting affects AMOC projections, even though it is of secondary importance. By years 2090-2100, the AMOC weakens by 18% [-3%, -34%; 90% probability] in an intermediate greenhouse-gas mitigation scenario and by 37% [-15%, -65%] under continued high emissions. Afterward, it stabilizes in the former but continues to decline in the latter to -74% [+4%, -100%] by 2290-2300, with a 44% likelihood of an AMOC collapse. This result suggests that an AMOC collapse can be avoided by CO2 mitigation.
Name
2-s2_0-85006788871.pdf
Type
Main Article
Size
3.54 MB
Format
Adobe PDF
Checksum
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