The relationship between ENSO events and sea surface temperature in the East (Japan) Sea

A relationship between ENSO events and variation of Sea Surface Temperature (SST) in the East Sea (Japan Sea) has been investigated using SST data compiled by the Japan Meteorological Agency (JMA) with 1 degree x1 degree resolution during 1950 to 1998. ENSO index used here is SST in the tropical Pacific Ocean. The results of the SST data analysis show that the variation of SST anomaly (SSTA) in the East Sea is closely related to ENSO events with the following features: 1) The summer in the year in which El Nino events develop (year 0) tends to be colder than in the year prior to the development of the El Nino events (year -1), i.e. `cold summer', whereas the winter tends to be `warm winter'; 2) The states in year 0 during La Nina events are opposite to those during El Nino events. A statistical correlation analysis supports the above results. EOF analysis of SST indicates that the first mode explains more than 90% of the SST variation. This paper shows that variation of SSTA in the East Sea occurs simultaneously with the development of ENSO events in the tropical Pacific Ocean.