53"
N
52"
51"
51"
62
3"
MARCH
JANUARY
FEBRUARY
51"
SEPTEMBER
OKTOBER
NOVEMBER
DECEMBER
3"
."
."
5°E
Figure 1. Monthly chlorophyll distribution in the Southern North Sea, showing the rapid temporal changes and
patchiness. Concentrations are mean values (p,g liter-I) for the usually well-mixed water column. Based on
surveys in the late seventies.
51"