Climatic Warming and the Decline of Zooplankton in the California Current

See allHide authors and affiliations

Science  03 Mar 1995:
Vol. 267, Issue 5202, pp. 1324-1326
DOI: 10.1126/science.267.5202.1324


Since 1951, the biomass of macrozooplankton in waters off southern California has decreased by 80 percent. During the same period, the surface layer warmed—by more than 1.5°C in some places—and the temperature difference across the thermocline increased. Increased stratification resulted in less lifting of the thermocline by wind-driven upwelling. A shallower source of upwelled waters provided less inorganic nutrient for new biological production and hence supported a smaller zooplankton population. Continued warming could lead to further decline of zooplankton.

Stay Connected to Science