UPWELLING AND THE PRODUCTION OF FISH
283
plankton zone was tabulated by year and area and averaged for the
10 years, ranging from 200-500 km. When the estimates from the
temperature distributions are compared with those from the distributions of zooplankton, the ratio of width of productive zone to
width of physical upwelling is 2.5. To treat all upwelling areas in the
same way, the width is estimated from surface temperature distributions, and is raised by 2.5.
135"
130"
125"
120"
115"
110"
I
I
I
I
I
L5" -
LO" -
3 0"
cc of plankta
FIG. 10. A typical distribution of zooplankton off California (Thrailkill, 1956); the
broken line is drawn at a median density.
283
plankton zone was tabulated by year and area and averaged for the
10 years, ranging from 200-500 km. When the estimates from the
temperature distributions are compared with those from the distributions of zooplankton, the ratio of width of productive zone to
width of physical upwelling is 2.5. To treat all upwelling areas in the
same way, the width is estimated from surface temperature distributions, and is raised by 2.5.
135"
130"
125"
120"
115"
110"
I
I
I
I
I
L5" -
LO" -
3 0"
cc of plankta
FIG. 10. A typical distribution of zooplankton off California (Thrailkill, 1956); the
broken line is drawn at a median density.