Changes in plankton communities. a, schematic comparison of the plankton communities in the past and the warmer present. b, surface chlorophyll-a concentration; c, total phytoplankton cell abundance; d, cell abundance of diatoms (blue) and dinoflagellates (yellow); e, zooplankton abundance; f, abundance of small jellyfish; g, the abundance ratios of small-sized (0.3–0.5 mm; blue) and large-sized (>0.5 mm; orange) copepods (Wang et al., 2023).