Connection between interannual variability of the western Pacific and eastern Indian Oceans in the 1997–1998 El Niño event*

Abstract

In this paper, the sea surface height and the heat content of the upper ocean are analyzed to retrieve the relationship of interannual variabilities between the tropical western Pacific and eastern Indian Oceans during the 1997 similar to 1998 El Nino event. In the prophase of this El Nino, the negative sea level anomalies (SLA) occurred in the tropical western Pacific (TWP) firstly, and then appeared in the tropical eastern Indian Ocean (TEI). The negative heat content anomalies (HCA) emerged in the TWP before this El Nino burst while the SLA signals developed over there. During the mature stage of this El Nino, two kinds of signals in the TWP and TEI turned to be the maximum negative sequently. Due to the connected interannual adjustment between the TEI and TWP, we adopted a method to estimate the Indonesian Throughflow (ITF) transport by calculating the HCA budget in the TEL The indirect estimation of the ITF was comparable to the observation values. Therefore, the anomalies in the TEI had been proved as advecting from the TWP through the ITF during the 1997 similar to 1998 El Nino.