Diagnostics of the La Niña events in 1900–2018

Abstract

Abstract Diagnostics of La-Nina events from 1900 to 2018 is done in this paper using COBE SST2 data sets. Two La Niña space-time types were selected on the basis of two methods. The first of them is empirical orthogonal functions method. The second one is hierarchical cluster analysis. Both of methods showed the absolute identity two selected types. Analyzing the spatiotemporal series of the sea surface temperature anomalies (SSTA) in the equatorial Pacific two main EOFs were obtained. The first EOF mode describes ∼46% of the total dispersion SSTA variability in the equatorial Pacific and demonstrated two consecutive La Niña events that arise after the strong canonical El Niño. The second mode accounts for ∼ 21% of the total dispersion SSTA variability and shows a nature of the East Pacific La Niña occurrence.