Seasonal teleconnection/ Indian Ocean
My current work is focused on the seasonal teleconnections from the Indian Ocean Dipole (IOD) to the North Atlantic Oscillation (NAO). Using perturbed model experiments of ECMWFs OpenIFS, I am analysing the strength and pathways of this teleconnection. A prominent example of a strong IOD event (that was crucially not in conjunction with an ENSO event) was the event in autumn and winter 2019/2020. During this winter, the IOD was in a positive phase (warm in the west and cold in the east), while the NAO was in a strong positive state as well. Additionally, the NAO was well predicted by most C3S models, which is an indicator for a strong tropical driver. Research has shown that in the Met-Office model, the tropical Indian Ocean is connected the North Atlantic via a Rossby-wavetrain, but there are still questions about the strength of this teleconnection in ERA5 and other seasonal forecast models (like SEAS5). An additional teleconnection pathway is via the interaction between mid-latitude eddies and the jetstream.