Fig. 5: Physical and ecological changes in the region across time.
a Annual cycle of Coastal Upwelling Transport Index (CUTI). b Biologically Effective Upwelling Transport Index (BEUTI). c Regionally available nitrate for the studied time period (2014-2020). Lines are 2-month moving averages and the color palettes represent three distinct time periods, 2014–2016 (red), 2017–2018 (blue), and 2019–2020 (gold). CUTI (m2 s−1) is a regionally integrated rate of vertical volume transport. BEUTI (μM m−1 s−1) is an estimate of nitrate flux into the surface mixed layer. Regionally available nitrate (μM) is the concentration of nitrate at the base of the mixed layer and can be calculated by dividing BEUTI by CUTI (see Jacox et al. 201847 for a full explanation). d Mean nitrate (μM) concentrations at 10 m depth at each CalCOFI station during the warm period (2014–2016). e mean nitrate concentrations during the cool period. f The difference in nitrate concentrations between the two phases (2014–2016) – (2017–2018). g–k Maps of the mean Bray-Curtis similarity92 between samples from the warm (2014–2016) and cool (2017–2018) phase for each station. Maps show surface samples for our five main groups (g Archaea, h Bacteria, i Cyanobacteria, j Photosynthetic Eukaryotic Protists, and k Heterotrophic Eukaryotic Protists). For DCM samples, see Supplementary Fig. 11.
