NAO and its predictability

Ake Johansson

Swedish Meteorological and Hydrological Institute
currently Visiting Scientist, EMC/NCEP/NOAA

The North Atlantic Oscillation (NAO) is the leading mode of variability in the extra tropical Northern Hemisphere. As such, its predictability is of major concern for operational centers. This seminar will review some aspects of our present knowledge and understanding of the NAO. It will include basic facts and recent findings on aspects such as its defintion, properties, postulated underlying physical mechanisms, predictability and forecast skill in NWP and climate models. It will conclude with a discussion of possible research directions relevant to improving its predictability in operational models at NCEP.