| Autor: |
R R Chapman, P Ashwin, J Baker, R A Wood |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Environmental Research Communications, Vol 6, Iss 11, p 111003 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
2515-7620 |
| DOI: |
10.1088/2515-7620/ad8f98 |
| Popis: |
The Atlantic Meridional Overturning Circulation (AMOC) exerts a major influence on global climate. There is much debate about whether the current strong AMOC may collapse as a result of anthropogenic forcing and/or internal variability. Increasing the noise in simple salt-advection models can change the apparent AMOC tipping threshold. However, it’s not clear if ‘present-day’ variability is strong enough to induce a collapse. Here, we investigate how internal variability affects the likelihood of AMOC collapse. We examine the internal variability of basin-scale salinities and temperatures in four CMIP6 pre-industrial simulations. We fit this to an empirical, process-based AMOC box model, and find that noise-induced AMOC collapse (defined as a decade in which the mean AMOC strength falls below 5 Sv) is unlikely, however, if the AMOC is pushed closer to a bifurcation point due to external climate forcing, noise-induced tipping becomes more likely. Surprisingly, we find a case where forcing temporarily overshoots a stability threshold but noise decreases the probability of collapse. Accurately modelling internal decadal variability is essential for understanding the increased uncertainty in AMOC projections. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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