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Ref. No. [UMCES] CBL 2016-016
ACT VS16-07
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Results for the Troll RDO for the two Lake Michigan trials are shown in figure 16. The
instrument underestimated DO when transitioning rapidly from surface equilibration into a colder,
high DO hypolimnion. Conversely when equilibrate in the hypolimnion the Troll RDO
overestimated DO levels when rapidly transitioned into the warmer, lower DO surface waters. The
range in measurement differences between instrument and reference was -0.59 to 0.07 mg/L for
cast 1 and -0.11 to 0.54 mg/L for cast 2. In both cases the Troll RDO appeared to approach
equilibrium by the seventh minute and the offsets declined to around 0.10 – 0.15 mg/L.
Figure 11
. Time series of the rosette profiling and Niskin bottle sampling for the two profiling trials in
Muskegon Lake.