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Transition Probabilities of Noise-induced Transitions of the Atlantic Ocean Circulation.

ABSTRACT: The Atlantic Meridional Overturning Circulation (AMOC) is considered to be a tipping element of the climate system. As it cannot be excluded that the AMOC is in a multiple regime, transitions can occur due to atmospheric noise between the present-day state and a weaker AMOC state. For the first time, we here determine estimates of the transition probability of noise-induced transitions of the AMOC, within a certain time period, using a methodology from large deviation theory. We find that there are two types of transitions, with a partial or full collapse of the AMOC, having different transition probabilities. For the present-day state, we estimate the transition probability of the partial collapse over the next 100 years to be about 15%, with a high sensitivity of this probability to the surface freshwater noise amplitude.

SUBMITTER: Castellana D

PROVIDER: S-EPMC6937345 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Transition Probabilities of Noise-induced Transitions of the Atlantic Ocean Circulation.

Castellana Daniele D Baars Sven S Wubs Fred W FW Dijkstra Henk A HA

Scientific reports 20191230 1

The Atlantic Meridional Overturning Circulation (AMOC) is considered to be a tipping element of the climate system. As it cannot be excluded that the AMOC is in a multiple regime, transitions can occur due to atmospheric noise between the present-day state and a weaker AMOC state. For the first time, we here determine estimates of the transition probability of noise-induced transitions of the AMOC, within a certain time period, using a methodology from large deviation theory. We find that there ...[more]

PMID: 31889057

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