Fig. 2

(a) Standard deviation of detrended net primary production anomalies (NPPA, shading) estimated by the standard vertically generalized production model and OI-SST anomalies (SSTA, blue contours, every 0.2 °C). The magenta region in (a) represents the coastal Dakar Niño Index region (CDNI, 9°N-18°N, 2°-coastal band). The dashed red line represents the isobath 2000 m. (b) Seasonal cycle of the standard deviation of CDNI-averaged detrended NPPA (red) and climatology (black) of the CDNI-averaged detrended NPP. (c) Same as (a), but for NPPA averaged in March-April-May (MAM) and SSTA averaged in February-March-April (FMA). (d) Monthly detrended CDNI-averaged NPPA. The horizontal green and blue dashed lines indicate the ± 0.8 standard deviation of the interannual NPPA. Green and blue shaded areas represent the extreme high and low NPP events, respectively, and are identified when the CDNI-averaged NPPA exceeds ± 0.8 standard deviation (± 0.551 gC m⁻² day⁻¹) for at least 2 consecutive months. Only the NPPA events that peak during MAM are highlighted by their corresponding years. All anomalies have been calculated over the period 2003/01–2023/12.