mojib latif geomar helmholtz centre for ocean research kiel and university of kiel
DESCRIPTION
A dynamical/statistical approach to predict multidecadal AMOC variability and related North Atlantic SST anomalies. monthly AMO index 1948 - 2012. Mojib Latif GEOMAR Helmholtz Centre for Ocean Research Kiel and University of Kiel. Thanks to M. Klöwer , H. Ding, R. Greatbatch , W. Park. - PowerPoint PPT PresentationTRANSCRIPT
A dynamical/statistical approach to predict multidecadal AMOC variability and related North
Atlantic SST anomaliesMojib Latif
GEOMAR Helmholtz Centre for Ocean Research Kiel and University of Kiel
Thanks to M. Klöwer, H. Ding, R. Greatbatch, W. Park
monthly AMO index 1948 - 2012
SAT trend 1980-2012
There is a marked inter-hemispheric asymmetry in the warming during the last decades, especially in the Atlantic
New analysis of North Atlantic surface heat fluxes since 1880
suggests that the ocean drives SST at decadal time scales
Can we predict the AMO given the large model biases?
CMIP5 multi-model mean SST bias (39 models)
model bias may prevent us from exploiting the decadal full predictability potential
The null hypothesis for multi-decadal AMOC variability
NAO-related SAT pattern (°C), +1σ
The NAO affects Labrador Sea convection which in turn drives AMOC (Delworth and Greatbatch, 2000; Eden and Jung, 2001)
The NAO drives convection in the North Atlantic, which in turn drives the AMOC
Latif and Keenlyside 2011
Dynamical/statistical approach to predict North Atlantic SST
1. force the Kiel Climate Model by NAO-related heat flux anomalies2. use the KCM‘s AMOC as predictor to statistically predict observed
North Atlantic SST
observed NA SST
Hindcast of the AMOC 1900-2010Kiel Climate Model forced by NAO-related heat flux anomalies
Klöwer et al. 2013
Link between the KCM‘s AMOC and observed North Atlantic SST
Klöwer et al. 2013
The Meridional Overturning Circulation (AMOC) and observed North Atlantic SST
AMOC leads SST by 21 years
Klöwer et al. 2013
AMOC lags SST by 10 years
Statistical link between the model‘s AMOC and the observed NA SST
Explained variances by the two CCA modes
AMOC lags SST by 10 years AMOC leads SST by 21 years
suggests a rather high decadal predictability potential of North Atlantic SST
Klöwer et al. 2013
Forecast of North Atlantic SST until 2030
Klöwer et al. 2013
Dynamical/statistical prediction based on the North Atlantic Oscillation and the Kiel Climate Model’s AMOC
Take home message
Climate models are useful tools to study the dynamics and predictability of climate variability and change. However, they suffer from large biases. Model improvement is a key issue during the next years.
In the meantime, hybrid approaches may prove useful.
The research leading to these results has received funding from the European Union 7th Framework Programme (FP7 2007-2013), under grant agreement n.308299NACLIM www.naclim.eu