El Niño-Pass Filtered SST
Filtering Details:
Penland and Matrosova (2004,2006) showed that the optimal structure seen on the Current projection of SST onto ENSO optimal structure was dominated by three empirically-derived normal modes (See also Penland and Sardeshmukh 1995). The time series here were first prepared as described in Description of SST predictions for three-month running mean SST anomalies in the global tropical strip. The resulting 20 EOFs were then projected onto the modal adjoints corresponding to the normal modes dominating the optimal structure, thus isolating the evolving nonnormal El Niño structure.
Product Details:
Forecasts are presented in a format consistent with those shown on Global Tropics SST.