Seasonality of synoptic eddy feedback and the AO/NAO
نویسنده
چکیده
[1] In this paper, by using a dynamic model with synoptic eddy and low-frequency flow (SELF) interaction, we show that the SELF feedback is of significant importance for the formation of the AO/NAO in both winter and summer. Although background storm activity is significantly weaker in summer than that in winter, the positive SELF feedback associated with the AO/NAO mode in summer can be as strong as that in winter. The seasonal variations of the AO/NAO patterns are found to resemble those of the leading singular modes simulated by a linear dynamic system with the SELF interaction in different seasons, and the seasonal shifts in spatial patterns of the AO/NAO are the result of the seasonal changes in climatological basic state and synoptic eddy activity. Citation: Pan, L.-L., and F.-F. Jin (2005), Seasonality of synoptic eddy feedback and the AO/NAO, Geophys. Res. Lett., 32, L21708, doi:10.1029/2005GL024133.
منابع مشابه
Dynamics of Synoptic Eddy and Low-Frequency Flow Interaction. Part II: A Theory for Low-Frequency Modes
Amidst stormy atmospheric circulation, there are prominent recurrent patterns of variability in the planetary circulation, such as the Antarctic Oscillation (AAO), Arctic Oscillation (AO) or North Atlantic Oscillation (NAO), and the Pacific–North America (PNA) pattern. The role of the synoptic eddy and low-frequency flow (SELF) feedback in the formation of these dominant low-frequency modes is ...
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