Premium
Impact of Indian Ocean Dipole on intraseasonal zonal currents at 90°E on the equator as revealed by self‐organizing map
Author(s) -
Iskandar Iskhaq,
Tozuka Tomoki,
Masumoto Yukio,
Yamagata Toshio
Publication year - 2008
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2008gl033468
Subject(s) - equator , pycnocline , indian ocean dipole , climatology , geology , forcing (mathematics) , stratification (seeds) , dipole , indian ocean , oceanography , sea surface temperature , latitude , physics , geodesy , seed dormancy , botany , germination , dormancy , biology , quantum mechanics
A neural network pattern recognition approach called self‐organizing map (SOM) has been used to examine the impact of the Indian Ocean Dipole (IOD) on intraseasonal zonal currents in the eastern equatorial Indian Ocean. This study shows that during negative IOD events the intraseasonal zonal currents are mostly dominated by the first two modes. On the other hand, contributions from the higher modes to the intraseasonal zonal current significantly increase during positive IOD events. This is attributed to the change in the background stratification associated with the IOD events; the sharp pycnocline in the eastern basin during the positive IOD events causes the wind forcing to project more onto the higher modes.