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The successful redeployment of float 47 is celebrated by posting the realtime profile of Nitrate from its ISUS sensor.

This illustrates both the advantages and problems with the new generation of biogeochemical sensors. The profile shows nitrate drawdown by about 4 uMol/kg in the euphotic zone above about 100m. On the other hand, the deep value of nitrate, 19 uMol/kg is much higher than the value expected in this area, about 14 uMol/kg at depth, so the sensor clearly needs a better calibration. This will be provided by water samples taken by the Knorr.

Nevertheless, the drawdown is only about 20% of the stock, so the bloom is a long way from nitrate limitation and will remain so for quite a while.