Studies on water movements and sediments in Southern Lake Michigan : part 1[-3] ... / by John C. Ayers.

comparisons movements of drogues were paired with no-current
indicated by dynamic heights. In only one of the nine was
there direct disagreement in direction between the computed
current and that indicated by drogue. In five of the nine
comparisons current velocity indicated by the two methods was
in order-of-magnitude agreement.
The comparison was carried out under north winds of 10 -18 knots which began during the early forenoon and continued
through the day. Winds of the 28th had been northwest 18-23
knots.
Double BT Run, Grand Haven to Milwaukee (Fig. l6)
On 23 October 1963 the vessels INLAND SEAS and MYSIS
carried out what was supposed to be a parallel run of bathythermograph soundings between Grand Haven and Milwaukee.
Inexperience with such runs is credited with the boats'
steering north of the course, and then converging after coursecorrection. Corrective measures have been taken.
Figure 16 presents the results of this run. The two
outer lines represent the paths of the two ships. Cross-lines
intersect the two ships' courses at the points where BT
soundings were taken. The center line connects the middlepoints of the "squares" which have BT soundings on each corner.
Current directions and velocities have been determined by
application of the dynamic height method: 1) along the track
of each ship, and 2) transversely to the ships' tracks along
the short cross-lines. Components of current: 1) normal to the
ships' tracks, and 2) parallel to the ships' tracks were thus

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