Fig. 2: Empirical orthogonal function (EOF) temporal patterns.
From: Modulation of ocean acidification by decadal climate variability in the Gulf of Alaska
Time series of the a Northern Gulf of Alaska Oscillation (NGAO) Index of satellite observed sea surface height (SSH) anomalies, b NGAO of modeled SSH anomalies, and the normalized principal components associated with the first Empirical Orthogonal Function (EOF) mode of c salinity, d temperature, e NO3, f pCO2, g saturation state for aragonite (Ωarag), and h pH. The EOFs were computed based on the illustrated spatial domain in Fig. 1. The amount of explained variance of each EOF is given in the lower-left corner of each map in Fig. 1. The EOFs were applied to monthly model output after first removing a long-term temporal trend using a quadratic function and second deseasonalizing the data. The Pearson correlation coefficients between the NGAO of the modeled SSH anomalies and each variable are given on the right side of the time-series of each variable (in bold when p < 0.05). The correlation coefficients designated with a star were based on low pass filtered data (6 years). Autocorrelation and the effective degrees of freedom were accounted for in this statistical analysis54. The black frame illustrates the time period of the ROMS-Cobalt hindcast simulation (1980−2013).
