Fig. 2: The relationship between the Winter Atlantic Niño and ENSO in the Historical and SSP585 simulations from CMIP6.

a The lagged correlation coefficients between the winter Atlantic Niño index (D[0]JF[1]) and the ENSO index (D[1]JF[2]) across 30 climate models from the Historical (pale blue, 1850–2014) and SSP585 (pale red, 2015–2100) simulations in CMIP6 are shown (Table 1). Their MMEs are illustrated on the leftmost side in blue and red. Black borders around each bar indicate statistical significance at the 95% confidence level based on the Student’s t-test, with degrees of freedom fixed at 120 for Historical and 70 for SSP585 simulations. Error bars for the MMEs represent the 95% confidence interval derived from a bootstrap method (10,000 times). b A scatter plot of correlation (x-axis) and regression (y-axis, °C) between the winter Atlantic Niño (D[0]JF[1], normalized) and the ENSO (D[1]JF[2], unnormalized) index is presented. Pale blue and pale red dots represent climate model results from the Historical and SSP585 simulations, with their MMEs marked by blue and red dots. The regressed lines are shown as dotted pale blue and pale red lines.