Stable Isotopes of Pteropod Shells as Recorders of Sub-Surface Water Conditions
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Fig. 1. Stable oxygen isotope composition «a): note inverse scale), species fluxes ofG. ruber (w) (fraction> 150 !lm)
(b), calculated ambienttemperature (c) in surface (about 30 m depth from G. ruber) and sub-surface waters (about
50 m depth from L. inflata) off Cape Blanc. In panel (d), measured weekly means of sea-surface temperature (SST)
at the study site are plotted. Annual means in estimated and measured water temperatures are indicated by horizontallines (c, d).