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There is increasing concern that the Atlantic Meridional Overturning Circulation (AMOC) may collapse this century with a disrupting societal impact on large parts of the world. Preliminary estimates of the probability of such an AMOC collapse have so far been based on conceptual models and statistical analyses of proxy data. Here, we provide observationally based estimates of such probabilities from reanalysis data. We first identify optimal observation regions of an AMOC collapse from a recent global climate model simulation. Salinity data near the southern boundary of the Atlantic turn out to be optimal to provide estimates of the time of the AMOC collapse in this model. Based on the reanalysis products, we next determine probability density functions of the AMOC collapse time. The collapse time is estimated between 2037-2064 (10-90% CI) with a mean of 2050 and the probability of an AMOC collapse before the year 2050 is estimated to be 59±17%.

The Atlantic meridional overturning circulation (AMOC) is a major tipping element in the climate system and a future collapse would have severe impacts on the climate in the North Atlantic region. In recent years weakening in circulation has been reported, but assessments by the Intergovernmental Panel on Climate Change (IPCC), based on the Climate Model Intercomparison Project (CMIP) model simulations suggest that a full collapse is unlikely within the 21st century. Tipping to an undesired state in the climate is, however, a growing concern with increasing greenhouse gas concentrations. Predictions based on observations rely on detecting early-warning signals, primarily an increase in variance (loss of resilience) and increased autocorrelation (critical slowing down), which have recently been reported for the AMOC. Here we provide statistical significance and data-driven estimators for the time of tipping. We estimate a collapse of the AMOC to occur around mid-century under the current scenario of future emi

The Atlantic Meridional Overturning Circulation (AMOC), a major ocean current system transporting warm surface waters toward the northern Atlantic, has been suggested to exhibit two distinct modes of operation. A collapse from the currently attained strong to the weak mode would have severe impacts on the global climate system and further multi-stable Earth system components. Observations and recently suggested fingerprints of AMOC variability indicate a gradual weakening during the last decades, but estimates of the critical transition point remain uncertain.

En 2019, la circulation routière en France métropolitaine se stabilise et atteint 623 milliards de véhicules-kilomètres. Les voitures et les véhicules utilitaires légers français et étrangers réalisent 92 % du trafic. En 2019, 28,5 % de la circulation des voitures a été réalisée par des véhicules essence (23,6 % en 2016) et 70,6 % par des véhicules diesel (75,8 % en 2016). Les autres motorisations (GPL, électriques, hybrides rechargeables) représentent moins de 1 % du trafic des voitures immatriculées en France en 2019. Une voiture immatriculée en France métropolitaine a roulé en moyenne 12 200 km dans l’année et un véhicule utilitaire léger 14 700 km. Les véhicules lourds immatriculés en France roulent beaucoup plus : 44 400 km pour un poids lourd et 34 300 pour un bus ou car. Avec 3 millions d’immatriculations en 2019, le marché des véhicules neufs croît de 3,2 % sur un an, après + 2,1 % en 2018. Les livraisons de supercarburant sont en hausse (+ 7,3 % en 2019 après + 3,8 % en 2018) et celles de gazole recu