Climate variability in marine environments, particularly sea surface temperature (SST), is influenced by natural fluctuations occurring at various temporal and spatial scales. Distinguishing between anthropogenic climate change trends and natural variability is crucial for understanding the complex dynamics of ocean temperatures. This study applies the concept of Time of Emergence (ToE) to estimate when the signal of long-term...

We develop a data assimilation scheme with the Icosahedral Non-hydrostatic Earth System Model (ICON-ESM) for operational decadal and seasonal climate predictions at the German weather service. For this purpose, we implement an Ensemble Kalman Filter to the ocean component as a first step towards a weakly coupled data assimilation. We performed an assimilation experiment over the period 1960–2014. This ocean-only assimilation e...