CLIMATIC EVOLUTION CHARACTERISTICS OF THE DIPOLE MODE OF SEA SURFACE TEMPERATURE IN THE TROPICAL INDIAN OCEAN
YANG Meng-xi
HU Rui-jin
LIU Mei
Abstract：Based on a total of 49a SODA data from January 1960 to December 2008,the climatic evolution characteristics of the tropical Indian Ocean dipole mode (IODM) of sea surface temperature are studied.The main results are as follows:(1) The IODM spatial patterns derived from the moving EOF (empirical orthogonal function) with 1a interval and 10a length do not always show the well-known distribution of the east-west dipole,but has an evolution from a south-north dipole to an east-west one;(2) In the case of the south-north dipole,the SST north (south) of 10 °S shows overall warming (cooling).For the east-west dipole,meanwhile,the SST in the tropical eastern (western) IO shows alternate variations of warming (cooling) and cooling (warming) on quasi-decadal timescales;(3) There are also four quasi-decadal variations in IODM,occurring in 1976,1987,1994 and 2005 respectively;(4) There is a reverse trend between the variance rate of the second mode (the IODM) and that of the first mode,in moving EOF.
Keywords：tropical Indian OceanSSTAmoving EOFIODMspatial-temporal evolution
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：10( 177-186 )