12C.2
Relationships between anomalous monsoons, meridional oceanic heat transport and the Indian Ocean Dipole in the NCAR CSM
Johannes Loschnigg, International Pacific Research Center, Honolulu, HI; and G. A. Meehl, P. J. Webster, J. M. Arbaster, and G. P. Compo
Analyses of the long term control integrations of the NCAR coupled ocean-atmosphere Climate System Model have been conducted with the aim of testing the relationships between the atmospheric and oceanic variability in the Indian Ocean-Monsoon region. It is found that the strength of the monsoon (determined by the vertical shear of the zonal winds over South Asia in JJAS) correlates negatively and significantly with the boreal summer meridional oceanic heat transport in the Indian Ocean. That is, during strong boreal summer monsoon years, there is larger quantities of southward (negative) oceanic heat transport, thus removing heat and reducing the heat content of the north Indian Ocean. At the same time, the sign and timing of the Indian Ocean dipole correlates negatively with the strength of the monsoon. That is, a strong monsoon leads to the formation of a negative dipole (warm water in the eastern Indian Ocean, warm in the western Indian Ocean) while a weak monsoon is associated with the opposite phase of the dipole. It is shown that the NCAR CSM appears to corroborate theories that suggest that the monsoon is regulated in amplitude by coupled ocean-atmosphere processes.
Session 12C, Ocean-Atmosphere Interaction I (Parallel with Sessions 12A, 12B, and 12D)
Thursday, 2 May 2002, 9:00 AM-10:30 AM
Previous paper Next paper