Stratospheric Dynamics and Climate Predictability

Predictions of the future state of the climate system are potentially beneficial to society. The stratosphere, which contains ~25% of the mass of the atmosphere at mid-to-high latitudes, has been recognized as a source of predictability at extratropical latitudes. Recent works have demonstrated that seasonal forecast systems initialized during Stratospheric Sudden Warmings lead to significantly larger skill in the extratropics. At the decadal timescales, sustained stratospheric anomalies can affect the ocean circulation in the North Atlantic implying a role of the stratosphere in decadal climate predictions. However, our lack of understanding of the stratosphere-troposphere coupling introduces uncertainty in climate projections. This talk will review our current understanding of the stratospheric variability and its relevance on climate predicability at different timescales.