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Ref. No. [UMCES] CBL 2015-011
ACT VS15-04
43
Figure 18.
Time series of pH measured by Troll 9500 pH sensor deployed during the 1 month GLERL
trial.
Top Panel
: Continuous pH
NBS
recordings from instrument (blue line) and pH
Total
of adjacent grab
samples determined by phenol red dye (red circles).
Bottom Panel
: Difference in measured pH relative to
reference samples (Instrument – Dye Ref) observed during deployment. Dashed line represent offset (ca
0.13) predicted due to difference in pH
NBS
and pH
Total
scales used by the Troll sensor and the dye
reference method.