Kimoto, M., A. Numaguti, T. Nakajima and M. Takahashi, 1995: Interannual variabilities simulated by CCSR/NIES AGCM with observed SSTs during 1979-1988. Abstracts of the First International AMIP Scientific Conference, Monterey, California, 40.

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Interannual variability simulated by a T21L20 version of the CCSR/NIES AGCM with 1979-88 SSTs is compared with observed circulation patterns. The overall magnitude of interannual variance in the troposphere is comparable, but somewhat smaller than, the observations. Grid-pointwise temporal correlations between simulated and observed seasonal-mean anomalies of zonal wind at 850hPa reach 0.8 in the eastern equatorial Pacific, but the correlation drops to insignificant values outside the tropical Pacific. The high correlation comes from large circulation changes associated with ENSO cycle. Equatorial low-level westerlies in the 1982/83 and 86/87 warm events and easterlies during the 1988 cold event are reasonably reproduced. However, even during these extreme phases of ENSO cycle, correspondence in circulation anomalies outside the equatorial belt in the Pacific is not particularly impressive. It appears important to simulate accurately the spatial distribution of precipitation anomalies not only in the immediate neighborhood of the largest SST anomalies but also in some key regions such as the western Pacific and Indian monsoon regions. Outside the tropics, little evidence of correspondence has been found between the simulated and observed circulation patterns except for dominance of westerlies over the North Pacific during the warm events. We would like to investigate the sensitivity of simulated variability in the tropics to model physics and to horizontal resolution, in tandem with an attempt to clarify the extent to which SST governs such variations.