Fig. 2: Composite evolutions of two types of multiyear La Niña events during the post-1970 period.
From: Understanding the recent increase in multiyear La Niñas
a,b, Three SE2ML events (1983–1984, 1998–2000, 2016–2017) (a) and five CPE2ML events (1970–1971, 1973–1975, 2007–2008, 2010–2011, 2020–2022) (b) showing SST (shading, °C) and 1,000 hPa zonal wind (contours, m s−1) anomalies. The stippled areas in SST denote a significance level of 0.05 by a two-tailed Student’s t-test. Horizontal purple lines indicate January (0) and January (1). There were only two double La Niña events before 1970, which followed a neutral ENSO state (Fig. 1a), differing from the eight multiyear La Niña events after 1970.
