File(s) not publicly available
The years of El Nino, La Nina and interactions with the tropical Indian Ocean
journal contributionposted on 2023-05-16, 19:37 authored by Meyers, GA, McIntosh, P, Pigot, L, Pook, M
The Indian Ocean zonal dipole is a mode of variability in sea surface temperature that seriously affects the climate of many nations around the Indian Ocean rim, as well as the global climate system. It has been the subject of increasing research, and sometimes of scientific debate concerning its existence/nonexistence and dependence/independence on/ from the El NiÃ±o-Southern Oscillation, since it was first clearly identified in Nature in 1999. Much of the debate occurred because people did not agree on what years are the El NiÃ±o or La NiÃ±a years, not to mention the newly defined years of the positive or negative dipole. A method that identifies when the positive or negative extrema of the El NiÃ±o-Southern Oscillation and Indian Ocean dipole occur is proposed, and this method is used to classify each year from 1876 to 1999. The method is statistical in nature, but has a strong basis on the oceanic physical mechanisms that control the variability of the near-equatorial Indo-Pacific basin. Early in the study it was found that some years could not be clearly classified due to strong decadal variation; these years also must be recognized, along with the reason for their ambiguity. The sensitivity of the classification of years is tested by calculating composite maps of the Indo-Pacific sea surface temperature anomaly and the probability of below median Australian rainfall for different categories of the El NiÃ±o-Indian Ocean relationship. Â© 2007 American Meteorological Society.
Publication titleJournal of Climate
Department/SchoolInstitute for Marine and Antarctic Studies
PublisherAmerican Meteorological Society
Place of publicationUnited States