GREAT LAKES RESEARCH I N STI T U T E SPECIAL REPORT NO. j GREAT LAKES RESEARCH DIVISION Institute of Science & Technology The University of Michigan Ann Arbor, Michigan THE CURRENTS OF LAKES MICHIGAN AND HURON JOHN C. AYERS ANN ARBOR THE UNIVERSITY OF MICHIGAN 1 959 TABLE OF CONTENTS Page.... ~~~~~~~~...................... v INTRODUCTION. THE "NORMAL" CURRENTS........ Lake Michigan............. The Straits of Mackinac....... Lake Huron.............. Drift Bottle Studies........... WATER TEMPERATURES.......... THE UNUSUAL CURRENTS......... Lake Michigan............ Lake Huron, Winds North of Normal Lake Huron, Winds South of Normal Drift Bottle Studies.......... IN CLOSING.................. Charts 1-20................. Tables 1-9.............................. 1............... 1........................ 2............ 4 ~........... 5........... 6............ 6............ 7............ 8............ 9............ 9 10 30 iii INTRODUCTION The information presented in this booklet is part of the results of a continuing program of research designed to provide various kinds of fundamental information that are needed in the solution of practical problems in the Great Lakes. Knowledge of the currents is one of these basic types of information. That currents directly affect navigation and recreational boating is obvious -- but that they also contribute to shore erosion, to silting-up of harbors, to the spreading of pollution, and to the distribution of fish-foods is not so evident though just as true. This pamphlet has been prepared by the Great Lakes Research Institute at the request of the Great Lakes Cruising Club. It presents in non-technical language our present information about the surface currents of Lakes Michigan and Huron. The material given here is an abridgment of more detailed technical information contained in "Currents and Water Masses of Lake Huron" and "Currents and Water Masses of Lake Michigan," both being publications of the Great Lakes Research Institute of the University of Michigan. No pretense is made that the surface currents shown here are the only ones possible, but there is a considerable body of evidence that the current patterns for prevailing-wind conditions (also called the "normal" currents) are representative of the usual currents in the two lakes. The current speeds obtainable from the current charts are average speeds. Local currents may vary from the speeds indicated on the charts by as much as tenfold, either faster or slower. No effort is made to indicate possible uses of the material contained in this booklet. The author, the Great Lakes Research Institute, the University of Michigan, and the Great Lakes Cruising Club are not responsible for incidents arising out of the use or misuse of the information here presented. Charts 1 and 2 give the common-place names referred to; they are included for the reader's convenience. v THE "NORMAL" CURRENTS Lake Michigan Charts 3 and 4 show the surface currents of Lake Michigan on 28 and 29 June 1955. On each of these days the lake was completely covered by the simultaneous cruises of eight vessels -- giving an overall picture of conditions in the whole lake on each day. Chart 19 shows the courses of the vessels and the sampling stations they visited. Winds prior to these coverages had been from quarters more or less normal for that time of year. In the author's opinion, the wind conditions (and hence the currents) in the southern half of the lake were somewhat more typical on 29 June than on 28 June, while in the northern half the wind directions at Escanaba and Sault Ste. Marie were more nearly from the prevailing directions on 28 June than on the 29th. It is believed that the normal current pattern is most accurately represented if the currents of 29 June for the region south of latitude 440 (Ludington - Manitowoc) are combined with those of 28 June for the region north of 44~. The "normal" current pattern described later will be from this combination of days. The southern half of the lake is sufficiently wide to exert a modifying effect on winds crossing it. Summer winds coming to the lower lake from southerly or westerly quarters are warm from their passage over the inland states. Upon moving out onto the lake, which is cooler than the air, the lower levels of the moving air are cooled by the lake and contract. The contraction of the lower air starts a descending motion in the moving air and barometric pressure over the lake will be somewhat higher than that over the land upwind. Cooling by the lake, setting up a descending motion in the moving air and causing over the lake a "high" of greater or less strength, should produce some tendency for winds to radiate around the "high" in a clockwise direction. The condition of clockwise effective wind directions around the southern half of the lake (arrows marked "W" in the charts) was somewhat better realized on 29 June 1955 than on the preceding day. The currents are driven by the wind but, because of the rotation of the earth, they move in a direction about 45~ to the right of the wind direction (arrows marked "T" in the charts). The somewhat more typical arrangement of wind directions on 29 June argues that the current pattern of that day will be somewhat nearer the "normal" than will the one of the 28th. Table 1 gives the winds of the periods of the Lake Michigan surveys. The southern half of Lake Michigan (in Chart 4) contains two dominant current features. A large flattened clockwise eddy commonly lies close to the Michigan shore and extends from off Grand Haven to Michigan City. Associated with this eddy are two smaller ones which are counterclockwise and which, in the lee of the shore from Little Sable Point to Benton Harbor and from Michigan City to Chicago, have currents contrary to the wind. The second major feature of the current pattern is the outflow current which rises from the Wisconsin shore at about Rawley Point, then flows southward (just off shore) to about the offing of Waukegan where it turns offshore and crosses to the central and east-central part of the lake; here it becomes associated with the west side of the large east-shore eddy and moves northward to come to the Michigan shore at Big Sable Point. Small clockwise eddies lying off Waukegan, off Kenosha, and off Milwaukee are associated with the outflow 2 current and are run by it as a large gear would run three small gears. Currents in the west-central part of the southern half of the lake appear to be weak, except from Michigan City northward to the offing of Waukegan. In the northern half of the lake (in Chart 3) the dominant feature is the outflow current which passes up the Michigan shore from Big Sable Point past Point Betsie and the Manitou Islands almost to Seul Choix Point on Michigan's Upper Peninsula. Off Seul Choix Point the current divides, with the larger portion making a U-shaped swing southward to pass below Beaver Island and approach the Straits of Mackinac from the southwest, and the smaller portion passing eastward above the Beaver Islands to the straits. The outflow current runs small clockwise eddies in the embayments between Big Sable Point and Point Betsie, between Point Betsie and Sleeping Bear Point, in Little Traverse Bay, and in Sturgeon Bay (Michigan). It also drives counterclockwise eddies situated off Naubinway, Port Inland, and Manistique on the Upper Peninsula of Michigan. On the west side of the northern part of the lake the currents tend to be southward with the outflow from Green Bay contributing part of the alongshore flow. A large counterclockwise eddy lies in the east-central part of the lake off Frankfort. The Straits of Mackinac Under prevailing winds the surface current in the Straits is to the east with division of the'&flow after it has passed Point Mackinaw. The major part of the current passes down South Channel, for prevailing winds are from the north of west. Minor portions of the current pass between Mackinac Island and Round Island; current speeds in this pass may be high as a result of the narrowness of the channel. Prevailing winds usually cause southward current between Mackinac Island and St. Ignace. Lake Huron Chart 5 shows the surface current pattern of Lake Huron on 29 June 1954. Three multiple-vessel single-day coverages of the lake were made during the summer of 1954; of the three the one shown is the most "normal." Chart 20 shows the courses of the vessels and the stations they visited. Winds prior to this coverage (Table 2) were more consistently from the prevailing directions than was true in the days before the other two. Further, the results shown in Chart 5 are confirmed by two previous all-shipping-season-long studies of currents which gave the same main current features but did not cover the lake so completely. There are two primary features in the Lake Huron current pattern: the flow-through current and the mid-lake eddy. The flow-through current is the belt of main current by which the inflows from Lakes Michigan and Superior pass along the length of the lake and arrive at the St. Clair River. The midlake eddy is a large counterclockwise eddy of current located in about midlake between Presque Isle and Cape Hurd. As was the case in Lake Michigan, smaller eddies are associated with, and driven by, both the primary current features. The flow-through current originates in the eastern part of the Straits of Mackinac. Lake Superior water emerging into Lake Huron through Mississagi 3 Strait, False Detour Channel, and Detour Channel flows westward along the north shore to about Les Cheneaux Islands. Here it meets the outflow from Lake Michigan and the two unite and turn southeast. The region of junction of the two waters is east of Mackinac Island and about north of the east end of Bois Blanc Island. The united flows move southeastward along the shore of Michigan's Lower Peninsula to Presque Isle. Just beyond Presque Isle the current leaves shore by continuing to the southeast while the shore trends southward. From Presque Isle to mid-lake at latitude 440 30' the outflow current is about 15 miles in total width with the strongest currents in the center seven or eight miles. In the offing of Thunder Bay the current begins to fan out gradually and the fanning out continues to mid-lake at 440 30' where the current separates into two branches. One branch (the smaller one) turns eastward for a few miles and then curves into a northward direction and enters the mid-lake eddy. The major portion (the flow-through current) is contained in the branch that moves west and reaches the Michigan shore throughout the region from Sturgeon Point to Oscoda. Flowing southward after reaching the Michigan shore, the flow-through current in part dips into the outer end of Saginaw Bay as far as Big Charity Island and in part crosses directly across the mouth of the bay. At Pointe aux Barques the current is again narrow and close to shore. From Pointe aux Barques the flow-through current moves northeast to the center of the lake, then turns south for about 35 miles. In mid-lake off Harbor Beach the current curves to the southwest and returns to the Michigan shore. It runs along shore to Lexington where it turns southeast and moves to the center of the lake and then curves southwestward. It reaches the St. Clair River as strong flow from the northeast in the eastern half of the extreme lower end of the lake. Associated with the flow-through current, and driven gear-wise by it, are five medium-to-small eddies of current. A clockwise eddy outside Thunder Bay and a small counterclockwise one in Thunder Bay are the first two of the five. Off the mouth of Saginaw Bay a medium-sized eddy is formed by the westward meander of the flow-through current. On the Ontario shore off Goderich is a counterclockwise eddy driven by the flow-through current. The final eddy of the five is a small clockwise eddy situated off Lakeport, Michigan. Returning to mid-lake at 44 30' and the eastward branch of current, we find that this branch is the chief contributor to the mid-lake eddy. From 440 30' this branch flows successively east, north, northwest, and southwest to rejoin the eastern side of the flow-through current in the offing of Presque Isle and thus to circumscribe the mid-lake eddy. A long flattened clockwise eddy driven by the mid-lake eddy is located along the Ontario shore from Cape Hurd to Clark Point. At the entrance to Georgian Bay, waters from this eddy and from the mid-lake eddy pass eastward into the bay. There is some evidence that average surface current in Owen Channel between Fitzwilliam Island and IManitoulin Island may be westward, but the evidence is not very conclusive and this current is not shown on the chart. On 29 June 1954 the east side of the mid-lake eddy showed a reversed-S of current between latitudes 450 00' and 450 30'. It is doubted that this is a permanent feature of the eddy. Until this is proven, the east- side of the eddy should be considered as being approximately parallel to the trend of the Canadian shore. Along the shores of Manitoulin, Cockburn, and Drummond Islands there are currents of some strength moving westward parallel to shore. The waters 4 involved in this flow appear to come mostly from the mid-lake eddy, with minor additions received from Mississagi Strait, False Detour Channel, and Detour Channel. Detailed studies in Saginaw Bay were carried out by the United States Fish and Wildlife Service in 1955. They confirmed the counterclockwise trend of currents which Chart 5 indicates as "estimated" in the inner end of the bay. The author greatly appreciates their permission to use this information. Drift Bottle Studies The drift of floating objects has provided man with both food for thought and information about currents since he first approached a sea-faring mode of life. Tropical woods stranded as driftwood on the coast of Ireland are cited among the several reasons that Columbus believed the "Indies" lay west of Europe. Few persons will pass an empty bottle on the beach without at least a stolen glance to see if it contains a "bottle note." Interest in the paths taken by flotsam stems from several causes. It may have a sanitation basis (as when a public health official suspects that the sewer outfall is upcurrent from the water intake), a more macabre undertone (the location or back-tracking of a drowned body), or any of several other causes, but generally it is nothing more than plain human curiosity. For many years use has been made of the beachcomber's natural "wonder where it came from?" to obtain information about currents. Bottle messages released at sea are accompanied by a return postcard upon which the finder is asked to report the date and place of discovery. The whole package of message, return card, and bottle is commonly called a "drift bottle." Charts 6 and 7 and Tables 3 and 4 show the release points and discovery points of 161 drift bottles released in Lake Michigan on 28 and 29 June 1955. Chart 19 shows the stations where the bottles were released. It is of course impossible to tell the actual path travelled by a drift bottle, but the direction of its movement is convincing evidence of the direction of the current. Since a drift bottle usually remains afloat for several days, its average rate of travel is an average of its movements in fast currents and in slow ones. The average current speeds obtainable from Charts 3, 4, and 5 have been derived from a complicated computation of the distribution of density of the water, but they have been checked by (and are in good agreement with) the average speeds of the drift bottles that travelled in the same regions. When several drift bottles are released at one place, the straight lines connecting release point to place of recovery may all run nearly side-by-side (indicative of strong currents) or they may fan out (indicating the successive stranding of bottles moving in a circular path). The paths of bottles released off Manistee in Chart 6 and just off Charlevoix in Chart 7 are good examples of the strong-current type of distribution; the movements of those released off Manistique in both charts show the fan-shaped distribution indicative of stranding from an eddy. Chart 8 and Table 5 give the release points and recovery points of 89 drift bottles from releases made in Lake Huron on 29 June 1954. Chart 20 shows the stations where releases were made. Strong-current distributions of the bottles are indicated in South Channel of the Straits of Mackinac, False Detour Channel, and at the extreme end of the lake near the mouth of the St. Clair River. Fan-shaped distributions indicative of bottles stranding out of eddies are shown off Goderich and along the Saugeen Peninsula. 5 One bottle of the Lake Huron releases obviously had human help in its travel, for it "moved" from the middle of the <south shore of Manitoulin Island to Oliphant, Ontario in 12 days. That it moved almost directly opposite to releases at nearby points, that it would have had to make more than half the straight-line trip against the currents, or that it would have had to travel at anomalously high speed to have made the trip around the mid-lake eddy in 12 days were points the prankish and not-too-honest finder failed to appreciate. WATER TEMPERATURES Chart 9 gives the distribution of surface water temperatures on 29 June 1955, one of the days of "normal" current pattern in Lake Michigan. Chart 10 shows a similar "'normal"t surface temperature distribution on 29 June 1954 in Lake Huron. In each of these charts the positions of eac h whole de gre e of Centigrade temperature have been connected by lines. Each of -these lines or isotherms should be considered as delimiting a "puddle" or band of water which was colder on one side of the line and warmer on the other. A "VI' lying on its side with the point to the right means "more than"; one with its point to the left means "less than"t and should be read with the number closest to it. Because Centigrade temperature values are not in general use -in this country, the following table of equivalent temperatures is included: 00 C or 32.0 Fahrenheit (freezing) 150 c or 59.0 F 6 C or 42.8 F 16 C or 60.8 F 70 C or 44.6 F 17 C or 62.6 F 80 C or 46.4 F 18 C or 64.4 F 9 C or 48.2 F 19 C or 66.2 F l O C or 50.0 F 20 C or 68.0 F 11~ C or 51.8 F 21~ C or 69.8 F 120 C or 53.6 F 22 C or 71.6 F (room temperature).130C or 55.4 F 230 C or 73.4 F 140 C or 57.2 F 240 C or 75.2 F The charted temperatures are for late June; they increase slowly during the summer and by late August may be as much as 40C higher in the shallower portions of the lakes. The very cold spot in the center of Lake Huron is a special case, it warms to about 16 0C or 60.8 0F by late Auglust when surf ace warming cuts off a rising of cold subsurface water there. Dashed lines on the temperature charts indicate that there is some uncertainty as to where the lines should go. Since temperature is the primary (but not the only) factor in determining the density of fresh water and since the distribution of density has been used in computing the probable current pattern, the reader might be interested in seeing the temperature distributions. Rough estimates of current direction can be made from the fact that the warmer water -is on the observer's right whe- n he faces in the direction that the current is going. 6 THE UNUSUAL CURRENTS Lake Michigan On 9 and 10 August 1955 multiple-boat single-day coverages of Lake Michigan were carried out. Winds at Chicago and Milwaukee were from easterly quarters on the 7th, 8th, and 9th; at Grand Rapids and Sault Ste. Marie they were from easterly quarters on the 8th and 9th; Escanaba had north winds on the 7th and south winds on the 8th and 9th; on the 10th the winds at all these stations were from westerly quarters, except at Chicago which had east winds. In other words, the surveys on the 9th and 10th came after winds which were from unusual quarters. The current patterns in the lake on these two days may be taken as representing the currents to be expected during the second day of a two-day easterly blow. Table 1 gives the winds that preceded all four of the Lake Michigan surveys. Currents in the lake do not respond immediately to wind changes, in fact the evidence indicates that the currents present on any given day reflect the wind directions plus rotation of the earth ("T" arrows around Lake Michigan charts) of the days prior to the one in question, but not of the day in question. If you are sailing today, you are encountering the currents set up by the winds of yesterday, the day before, the day before that, etc., but the effects of today's winds will not be showing until tomorrow. The effectiveness of previous winds in today's current pattern falls rapidly as the days become farther in the past. Yesterday's winds would be ranked, for example, as 1; those of the day before as 1/2; those of the day before that as 1/4, etc. For practical purposes the winds of the preceding four or five days are usually all that need be considered, but to be strictly accurate about ten days need to pass before the effects of a day's winds are completely gone from the current pattern. The "W" arrows on the Lake Michigan charts are the effective wind direction of the preceding ten days. Today's winds spend their energies changing the current pattern left by yesterday; the changed pattern will be operative tomorrow at the soonest. If today's winds are from the same direction as yesterday's, their effects will show in increased current speeds tomorrow. If today's winds are opposite to those of yesterday, they will show as slowed currents, stopped currents, or reversed currents tomorrow according to whether today's winds are weaker, equal to, or stronger than yesterday's. Wind shifts amounting to less than actual reversal of direction will cause changes in both the directions and speeds of the currents, as a moving billiard ball when struck by the cue ball takes up a new direction and a new speed that combine those it originally had with those it received from the cue ball. Chart 11 gives the currents in Lake Michigan on the second day of an easterly blow (third day at Chicago). The dominant feature in the current pattern on this day, 9 August, was a strong and wide southward current along the east shore from the Straits to Chicago. The large eddy found against the Michigan shore under "normal" winds was displaced to the center of the lake. The outflow current also was crowded away from the Michigan shore. It ran almost up the middle of the lake as far as the offing of Frankfort where it crossed to the mouth of Green Bay and then went eastward along the shore of the Upper Peninsula of Michigan. In the western part of the Straits of Mackinac the outflow current was denied escape into Lake Huron by the water transport direction ("T" arrow) accompanying the winds in the Straits. 7 The water transport direction in the Straits appears to be the key to the whole current pattern in Lake Michigan. When the effective wind direction (resulting from the preceding few days' winds) is from too far north or east the accompanying water transport direction is headed back into Lake Michigan and surface outflow to Lake Huron is stopped. At such times the outflow current turns down the east shore of the lake and reinforces the southward current which is being formed by the T-arrow water transport forces. At such times, also, Lake Huron water is pushed into Lake Michigan through the Straits. The levels of the two lakes are kept in balance at such times by a subsurface flow of water from Lake Michigan into Lake Huron. In Chart 11, on the second day of the easterly blow and before the full effects of the blow had developed, northeast effective winds with westward water transport were pushing the currents away from shore in the Grand Rapids area. In the Chicago region they were drawing the east-shore south current over to the city. At Milwaukee they were moving water toward shore but its effect would not be fully expressed until the next day. At Escanaba the water transport direction was such as to draw water in through the mouth of Green Bay (and probably produce strong eastward current in Sturgeon Bay Canal). In Chart 12, after two full days of easterly winds (three at Chicago) the east-shore south current was wide and extended out to the center of the lake. The large clockwise eddy normally against the Michigan shore in the southern part of the lake had been pushed over against the Illinois shore in the region between Wilmette and the Wisconsin boundary. At Milwaukee, water had been transported onto shore until it made a wind set-up, or hill of water, and on the slope of this set-up current ran south as it should under such conditions. The outflow current was broken at latitude 43~ 45'. The southern part flowed eastward below Milwaukee to join the east-shore south current; the remainder formed a large and flattened eddy off the mouth of Green Bay. Except for Grand Traverse Bay and the eddy off Naubinway, the eddies in the northern half of the lake were reversed in current direction from their normal condition. Lake Huron, Winds North of Normal In Chart 13 is shown the current pattern of Lake Huron on 27 July 1954. This survey followed winds (Table 2) which, in the Straits region, were from the "normal" west northwest direction during the days before the survey. Consequently, the currents in the upper end of the lake were essentially as in the normal pattern given in Chart 5. A small eddy in South Channel was the only well-substantiated difference. A scanty amount of evidence suggested that there might have been eastward current along the shores of Drummond, Cockburn, and Manitoulin Islands, but there was little certainty of it. In the central part of the lake the winds during the week prior to 27 July had been from the north for three consecutive days (Table 2) and the currents appeared to be recovering from the southwestward distortion that such winds would have imposed upon them. The recovery was not being materially helped by northwest winds just before the survey. North winds blow south but the rotation of the earth converts the wind energy into a water-moving (water transport) force about 45 to the right of the wind movement, i. e., a north wind tends to move water to the southwest. In the same fashion northwest winds blow southeast but move water south. The flow-through current off Thunder Bay was just off the Michigan shore, but still made a westward turn to come shoreward in the region from Sturgeon 8 Point to Oscoda. It still travelled south along the shore past Tawas Point and dipped into Saginaw Bay. The eddy that normally lay off the mouth of the bay was almost against shore at Oscoda. The flow-through current emerged from Saginaw Bay along the south shore of the bay mouth, but instead of going northeastward to mid-lake it passed in a southeasterly direction almost to the Ontario shore from whence it moved southwest to the St. Clair River. The mid-lake eddy was almost non-existent on 27 July. All that remained of it was a circular arrangement of weak currents off Macpherson Point. A weak eastward branch of the flow-through current left that current at about 44~ 10' and passed northeastward along the side of the remnant of the mid-lake eddy. Another eastward branch of the flow-through current left the east side of that current in latitude 44 45' and crossed almost to the Saugeen Peninsula. This is interpreted as being the beginning of the re-establishment of a normal mid-lake eddy as the result of the west and northwest winds of the days just prior to the survey. In the southern end of the lake the winds (Table 2) had been from the north and northeast for six days prior to the survey of 27 July. The southward and westward displacement (of currents) resulting from these winds causing the flow-through current to slant southeastward across the lake instead of going northeast to mid-lake then south and southwest to reach the Michigan shore below Harbor Beach. The counterclockwise eddy which "normally" was situated off Goderich was, on the 27th, at Grand Bend. Lake Huron, Winds South of Normal On 25 August 1954 Lake Huron was surveyed after the winds over the central and southern parts of the lake had been from the south and east for four of the preceding seven days (Table 2). Chart 14 presents the current pattern in the lake on 25 August. Again, winds in the Straits region were from essentially the normal west northwest, and again the currents in the upper portion of the lake were not materially modified from the normal condition. In the central portion of the lake the currents were displaced to the east and north. The flow-through current was deflected to the eastward at Presque Isle and flowed eastward and northeastward to Manitoulin Island. In doing so, it passed around the south end of the mid-lake eddy which was displaced northward and was centered about at the Duck Islands. Currents directed off the shore arose along the Michigan coast from Oscoda to Thunder Bay. About half of these turned eastward above Thunder Bay and crossed to Cape Hurd, from there they went northwest along the shore of Manitoulin Island and up the east side of the mid-lake eddy. The other half turned eastward above Thunder Bay but then went south almost to Pointe aux Barques. Here they curved northeastward and crossed into the east-central part of the lake off Macpherson Point. From there a part went northeast along the Saugeen (Bruce) Peninsula and a part flowed south along the center of the lake. The clockwise eddy normally situated at the mouth of Saginaw Bay was displaced to the north and east and lay about a third of the way across the lake. Inflow into Saginaw Bay appeared to be up the center of the bay mouth and outflow from the bay was along its south shore. In the southern end of the lake, northeast currents rose from the shore between Lexington and Harbor Beach. These in part turned south in mid-lake east of Pointe aux Barques and in part joined the cross-lake current from Saginaw Bay and went to the offing of Macpherson Point before returning south 9 down the center of the lake and approaching the St. Clair River from the northeast. The small clockwise eddy normally off Lakeport was pushed up to the offing of Lexington. Drift Bottle Studies Charts 15 and 16 and Tables 6 and 7 give the release and discovery data on 78 drift bottles recovered from releases in Lake Michigan on 9 and 10 August 1955. These releases accompanied the unusual current condition in the lake and the movements of the bottles as well as their average speeds have been used as checks on the current directions and speeds of Charts 11 and 12 which were deduced primarily from the distribution of water density. These drift bottles have been studied and used in the same way as were those accompanying the normal currents. No additional comment is considered necessary for the bottles of 9 August. The bottles released on 10 August fall into two groups, on the basis of their movements. Those recovered in less than four days (see Table 7) moved in directions that indicate they were carried by the unusual current condition present on 10 August. Those found and reported after four days or more moved in directions not like those of the unusual current pattern, but like those of the normal current pattern. They are believed to have stayed adrift until after the unusual currents had ceased and the winds and currents had returned to normal or nearly so. Charts 17 and 18, and Tables 8 and 9, give the drift bottle data for the unusual current conditions in Lake Huron. IN CLOSING Abridgment such as has been made here is never completely successful. The omissions and condensations that are necessary always result in the loss of explanatory material, and sometimes result in ambiguities where the reader obtains an idea quite different from that being presented. The author honestly believes that he has been successful in avoiding ambiguities, but he also has a healthy pessimism about the matter. The material presented here has been abstracted from the surface temperature, drift bottle, and composite surface currents sections of the two full-fledged works indicated earlier. The perplexed reader is referred to them, they are not as difficult as they may look. 10 I IS. BAY CANAL PT. BIG SABLE I LITTLE SABLE 88~ Chart 1 A) 12 SYNOPTIC '2 28 JUNE 1955 ' A ll t ' * 4ff PI t' t pi I s, q ~k'A L \ i r 't Chart 3 13 - ' / SURFACE CURRENTS ) / N SYNOPTIC 3 29 JUNE 1955 A/ I /' 7c USE ARROW FOR DIRECTION USE CHORD FOR VELOCITY.. > -TENTATIVE '.. \ \\ *.. GA/Is r Chart 4 14 Chart 5 15 DRIFT BOTTLE RECOVERIES SYNOPTIC I: 28 JUNE 1955 e = RELEASE POINT Chart 6 16 DRIFT BOTTLE RECOVERIES SYNOPTIC I 29 JUNE 1955 O a RELEASE POINT Chart 7 in.:31 A) ell, 00 t —d I -4 18 Chart 9 0 20 Chart 11 21 Chart 12 ND, a p Ci (:2 C-t1 I 24 DRIFT BOTTLE RECOVERIES SYNOPTIC ZI9 AUGUST 1955 e a RELEASE POINT Chart 15 25 DRIFT BOTTLE RECOVERIES SYNOPTIC Im 10 AUGUST 1955 e = RELEASE POINT Chart 16 --- --— 46" -45 FROM CRUISE SYNOPTIC, I - - -RELEASE POINT 3 - 2 BOTTLES TO LAKE ST CLAIR, 5 TO ST CLAIR RIVER 81 80 0 *17 w% 28 I -wF14 16 COURSES 34 14STATIONS40 y9 \ SYNOPTIC CRUISES N- & 112uA 28829 JUNE 195 4 - 30 % 28 TEMPERATURE STATION It4 1 a 19JU E 1 12A 11 8A 811 8,A SN I 5116, / COURSES a STATIONS -- r'a TE OMPLERATUE STATION Chart 19 '*1 0 30 Table 1. Wind data, Lake Michigan, 1955. Dir. = prevailing direction; mph = average velocity, mph. Date 29 June 28 27 26 25 24 23 22 21 20 19 10 August 9 8 7 6 5 4 3 2 1 31 July Chicago Dir. mph SSW 10.4 S 8.1 ENE 7.0 ENE 7.1 NE 9.6 E 6.9 NW 8.5 NW 10.9 NW 10.8 WNW 6.6 SW 9.2 E 4.7 E 5.8 ENE 9.8 NNE 12.7 WNW 8.3 SW 7.5 SW 10.4 SW 10.1 E 6.0 E 6.7 S 6.3 Milwaukee Grand Rapids Dir. mph Dir. mph Escanaba Sault Ste.Marie Dir. mph Dir. mph SSW 13.1 SSW 12.4 ESE 8.1 ENE 6.3 ENE 9.4 W 8.6 WNW 11.0 WNW 17.7 WNW 15.1 SW 8.1 S 5.9 WNW 9.8 ESE 8.6 ENE 14.2 NE 20.1 SSW 8.6 SW 9.8 SW 13.1 SW 12.1 E 6.3 NNE 7.2 SW 9.8 SSW 6.8 NW 3.5 NW 2.4 N 6.1 NNW 5.5 WNW 6.0 WNW 5.6 NW 9.3 WNW 8.4 W 4.3 ESE 3.1 WNW 4.3 E 5.2 E 8.3 N 10.0 S 6.1 W 8.2 W 9.0 W 7.1 WNW 4.6 NW 5.4 W 4.5 S S S NW N N S NW NW S S NW S S N N N S S N S SW 9.3 9.2 7.1 6.2 11.5 7.6 5.7 13.6 11.1 7.7 8.0 9.3 9.4 6.5 16.8 6.1 10.2 6.5 6.6 6.2 7.1 7.5 SE 5.4 SW 5.1 W 7.5 WNW 9.6 NW 9.3 WNW 8.6 WNW 9.3 WNW 12.8 WNW 10.9 SW 5.9 SW 7.4 WNW 7.5 SE 8.4 ENE 5.2 NW 12.7 ESE 7.1 WNW 8.4 WNW 7.6 SE 4.8 WNW 5.5 WNW 5.2 SW 6.8 31 Table 2. Wind data, Lake Huron, 1954. Dir. = prevailing direction; mph - average velocity, mph Date 29 June 28 27 26 25 24 23 22 21 20 19 27 July 26 25 24 23 22 21 20 19 18 17 25 August 24: 23 22 21 20 19 18 17 16 15 Sault Ste. Marie Dir. mph ESE 7.4 WNW 4.6 WNW 12.5 WNW 8.6 ESE 3.5 SSW 8.5 WNW 7.0 WNW 9.1 E 5.4 SW 9.1 WNW 4.2 SSW 4.8 WNW 6.7 WNW 8.4 WNW 8.7 WNW 4.3 NW 7.6 WNW 7.6 WNW 7.3 SE 6.0 WNW 9.4 E 7.3 W 7.6 WNW 5.3 ESE 8.7 ESE 8.6 WNW 4.8 WNW 7.8 WNW 9.9 E 6.9 WNW 7.9 NW 12.0 W 6.1 Alpena Dir. mph SE NW NW NW S SW NW W SE S SE SW W NW NW NW N N N SE NW S W W S SE SE NW NW S NW NW NW 7.7 6.6 17.0 8.0 4.7 7.4 9.3 10.5 8.1 9.3 5.1 7.0 7.7 8.7 6.8 7.6 6.8 7.8 8.8 10.1 11.3 6.3 9.8 6.0 8.7 8.4 6.8 7.1 10.3 11.7 8.3 13.4 7.3 Detroit Dir. mph N 3.8 N 10.1 NNW 14.3 NW 11.3 WSW 10.7 S 7.2 NNW 10.8 WNW 14.6 SW 10.1 SSW 8.0 S 8.3 WNW 7.8 N 5.2 NE 5.6 N 4.9 N 4.1 NE 8.6 NNE 10.5 SW 11.0 NW 7.5 S 9.2 SSE 6.3 W 8.4 W 10.7 S 6.8 E 7.7 ENE 7.0 N 7.1 W 9.7 SSE 6.5 N 6.6 W 9.5 W 8.3 Table 3. Drift bottle data, Cruise Synoptic IV, 28 June 1955. w CO Release Bottle No. station 3396 101 3360 105 3298 110 3297 110 3295 110 3294 110 3291 110 2924 111 2923 111 2922 111 2619 116 2617 116 2616 116 2485 117 2481 117 2599 118 2598 118 2477 118 2505 121 2510 121 2528 123 2527 123 2523 123 2533 124 2535 124 2537 124 2544 125 2543 125 2545 125 *Calculated as 1/2 day. Recovery location 41~55.1',87037.2' 43000.9', 87053.2' 42040.3', 86013.0' 42049.8', 86012.8' 42050.7', 86012.9' 42047.2', 86012.9' 42028.9', 86014.8' 43031.0',86028.8' 43022.3',86025.8' 43022.3',86025.8' 43051.2',86025.9' 43050.0',86025.9' 43050.0', 86025.9' 45003.7', 86000.0' 45000.0', 86006.6' 44016.4',86019.1' 44025.1',86015.1' 44043.6',86009.4' 44056.8',85048.8' 45006.8', 85036.0' 45004.5',85035.8' 45005.2',85041.3' 45010.4', 85037.9' 45011.4',85031.8' 45012.2',85033.5' 45035.7',85006.4' 45008.2',85033.8' 45021.8', 85006.5' 45021.8',85005.2' Recovery date 12VII55 20VII55 5VII55 5VII55 6VII55 8VII55 1VII55 2VII55 29VI55 30VI55 28VI55 28VI55 29VI55 17VII55 18VII55 26VII55 15VII55 18VII55 3IX55 15VII57 23VII55 23VII55 24VII55 22VII55 lOVII55 25VII55 8VIII55 17VII55 11VIII55 Days adrift 14 22 7 7 8 10 3 4 1 2 0* 0* 1 19 20 28 17 20 67 2 25 25 26 24 12 27 41 19 44 Miles traveled 32 50 20 30 31 27 7 10 1 1 5 4 4 91 85 37 47 68 74 90 66 72 79 76 112 90 107 110 Av. speed mph 0.10 0.09 0.12 0.18 0.16 0.10 0.10 0.04 0.02 ca 0.40 ca 0.30 0.17 0.20 0.18 0.12 0.14 0.05 0.15 0.11 0.12 0.26 0.23 Table 3 (cont.) Release Recovery Recovery Days Miles Av. speed Bottle No. station location date adrift traveled mph 2727 126 45040.8' 85030,3' 22VII55 24 81 0.14 2728 126 45021.3',85011.7' 11VII55 13 75 0.24 2734 127 45020.2', 8a14.1' 10VII55 12 61 0.21 2706 127 45023.5',84054.9' 11VII55 13 90 0.29 2707 127 45009.8 ',85033.4' 8VII55 10 62 0.26 2733 127 45021.8',85005.5' 2VIII55 35 80 2714 128 45020.2', 85014.7' 16VI155 18 73 0.17 2715 128 45044.7',85030.0' 7VIII55 40 83 2718 129 45018.8',85017.2' 27VII55 29 73 0.10 2813 130 45045.1 ',84059.3' 8VIII55 41 100 0.10 2812 130 45019.2', 85017.0' 31VII55 33 78 0.10 2662 130 45021.4', 85011.4' 9VIII55 42 83 0.08 2661 130 45018.2',85019.0' 31VII55 33 78 0.10 2693 131 Lime Kiln Pt., Bois Blanc Is. 1X55 95 113 2694 131 45057.9',85039.8' 30VII55 32 65 0.08 2234 131 45048.3',85031.3' 14XII55 169 65 2233 131 46005.6',85019.8' 1IX55 65 82 2107 139 Lime Kiln Pt., Bois Blanc Is. 31VII55 33 55 2109 139 Lime Kiln Pt., Bois Blanc Is. 30VIII55 63 57 2832 139 45~43.4', 8456.7' - - 2835 139 45047.3', 84045.7' 14VII55 16 46 0.12 2831 139 45045.9', 85001.1' 10VII55 12 31 0.11 2108 139 South shore, Bois Blanc Is. 12VII55 14 65 0.19 2833 139 45043.4',84056.7' 16VII55 18 32 2825 140 45~44.6 ',85~39.5' 9VII55 11 19 0.07 2420 140 45041.9',85040.4' 19VIII55 52 16 2417 140 45021.4',85~11.4' - 2416 140 45018.4',85017.2' 24VII55 26 17 2826 141 46~00.8',85~01.9' 16VII55 18 45 0.10 3978 141 Grace Harbor, Hammond Bay 3VIII55 36 96 0.11 2829 141 45058.0',85039.3' 24VIII55 57 26 CO 00 co Up^ Table 3 (cont) Release Recovery Recovery Days Miles Av. speed Bottle No. station location date adrift traveled mph 3974 142 46004.1',85017.9' 17VII55 19 39 0.08 3981 142 45053.0',84048.8' 10VII55 12 56 0.19 3982 142 46005.3',85019.9' -- 2839 142 45055.2',84054.7' 25VII55 27 51 0.08 2837 142 45053.8',84051.0' 28VII55 30 53 3976 142 46005.6',85028.4' 2V56 309 35 2838 142 Hammond Bay, Lake Huron 24VII55 26 97 0.16 2466 143 45057.7', 86002.4' 29VII55 31 9 2467 143 45057.7',86002.4' 29VII55 31 9 2468 143 45057.7', 86002.4' 29VII55 31 9 3973 143 45057.7',86002.4' 29VII55 31 9 2470 143 45057.6 ',86001.4' 5VII55 7 9 0.05 2469 143 45056.8',85059.0' 22VIII55 55 9 2857 144 45056.8 ', 85059.0' 22VIII55 55 10 2859 144 45057.8', 86~07.1' 22VII55 24 5 2426 144 4557.1', 86009.3' 11VIII55 44 3 2430 144 45~56.1', 86~16.9' 17VII55 19 5 0.01 2428 144 45057.6',86007.9' 11VII55 13 4 0.01 2429 144 45057.8', 86003.0' 12VII55 14 7 0.02 2856 144 45056.9',85059.7' 27VII55 29 9 2858 144 45057.2', 86000.5' 29VII55 31 9 3970 149 45053.7', 84050.7' 1VII55 3 9 0.13 3969 149 45054.8', 84052.8' 2VII55 4 7 0.07 3971 149 45054.2', 84052.2' 20VII55 22 8 3966 149 45054.2', 84052.2' 15IX55 79 8 3953 150 45053.7',84050.7' 1VII55 3 9 0.13 3949 150 45053.7', 84050.7' 1VII55 3 9 0.13 3962 151 45054.2', 84052.2' 1VII55 3 14 0.19 3961 151 45054.2', 84052.2' 5VII55 7 14 0.08 3965 151 45~52.1',84049.4' 28VII55 30 15 3963 151 45053.8', 84051.0' 28VII55 30 15 3964 151 45053.8', 84051.0' 27VII55 29 15 __ Table 4. Drift bottle data, Cruise Synoptic V, 29 June 1955.. Release station Bottle No. 3339 3400 2932 3340 3296 3290 2983 2981 2982 2978 2904 2496 2640 2630 2547 2582 2584 2548 2549 2580 2554 2552 2227 2704 2818 2687 2690 2820 *Calculated as 1/2 day. 101 101 105 109 110 110 111 111 111 112 115 117 118 120 121 121 121 121 121 124 125 125 133 133 134 134 134 134 Recovery location 41043.2',86055.7' 41043.3',86055.2' 42054.8', 87050.5' 41049.8',87036.1' 42031.4',86014.8' 42034.0',86014.4' 43056.2 ',86027.5' 43037.3 ',86032.2' 44039.6', 86015.1 44043.3',86007.9' 43044.4', 87043.1' 45023.2',85007.5' 44033.4',86013.9' 44009.0', 87033.2' 45~00.8',87008.4' 45004.2',87005.9' 45000.5',87009.6' 45003.7',87004.8' 45003.6', 87007.3' 44047.2',85037.8' 44053.9',85033.0' 45003.8 ',85035.0' 45047.5',86021.5' 45037.0',86038.7' 45056.1',85058.0' 45055.0',85~55.0' 450574', 85055.1' 46006.0', 85024.8' Recovery date 6VII55 6VII55 28VII55 10VIII55 3VII55 21VII55 1VII55 19VII55 12VIII55 13VII55 19VIII55 1OVII55 29VI55 8VII55 9VII55 12VII55 4IX55 18VII55 22VII55 1IX55 12VII55 1VIII55 16X55 31VII55 21VII55 1VIII55 5IX55 Days adrift 7 7 29 42 4 22 2 20 44 14 51 11 0* 9 10 13 67 19 23 64 13 33 109 32 22 33 129 Miles traveled 3 3 41 65 10 41 18 61 107 49 142 58 5 14 18 13 18 16 111 113 96 20 4 39 39 42 65 Av. speed mph 0.02 0.02 0.06 0.06 0.10 0.37 0.10 0.15 0.12 0.22 ca 0.40 0.07 0.08 0.04 0.20 0.31 0.03 0.05 0.07 0.05 Cll _ __ _ ~ Table 4 (cont.) Release Recovery Recovery Days Miles Av. speed Bottle No. station location date adrift traveled mph 2666 135 45018.6 ',85018.8' 27VII55 28 48 0.07 2668 135 45038.3',85003.4' 9VIII55 41 65 0.07 2651 135 45021.1',85~13.0' 24VII55 25 53 0.09 2218 137 St. Ignace 11VII55 12 92 0.32 2220 137 South Channel, Straits of Mackinac 13VII55 14 91 0.27 2216 137 45045.4',84057.8' 10VII55 11 77 0.29 2217 137 45025.4',84059.5' 13VII55 14 59 2219 137 45023.6',84055.2' 6VII55 7 63 0.38 2432 139 St. Ignace 15VII55 16 55 0.14 2431 139 45044.7',84054.4' 12VII55 13 40 0.13 2435 139 45045.4',84056.0' 12VII55 13 39 0.13 2433 139 45051.0',84053.0' 2VIII55 34 43 2434 139 45045.7',84059.0' 14VII55 15 35 0.10 2438 140 45033.1',85036.3' 5IX55 68 13 2436 140 45041.8',85040.8' 16VIII55 48 18 2440 140 45045.4', 85034.0' 6X55 99 23 2442 140 North side Bois Blanc Island 12VIII55 44 58 2445 140 45033.9',85036.7' 9VIII55 41 15 2443 140 45045.2 ',85031.0' 1OVII55 11 21 0.08 2456 141 45055.4',84054.0' 25VII55 26 49 0.08 2464 141 46000.9',85001.7' 31VII55 31 45 2460 141 45056.5 ',84056.0' 21VII55 22 48 0.09 2447 142 45052.9', 85051.4' 8VII55 9 21 0.10 2453 142 45052.2', 84050.1' 25VII55 26 56 0.09 3968 143 45056.5',86014.6' 11VII55 12 12 0.04 2854 143 45057.4',86010.7' 12VII55 13 11 0.04 3992 143 45057.2',86009.9' 10VII55 11 10 0.04 3980 143 45057.1 ',86000.8 29VII55 30 9 2106 143 45057.1',86000.8' 29VII55 30 9 2853 143 45057.1',86000.8' 29VII55 30 9 2851 143 45057.1',86000.8' 29VII55 30 9 Bottle No. 2423 2422 2024 2025 2022 2030 2026 2031 2033 2035 Release station 144 144 148 148 148 150 150 151 151 151 Recovery location 450565 ', 86014.6' 45057.5',86012.0' North tip of Mackinac Island 45055.4',84054.0' 45054.6', 84055.0'** Rogers City 45051.0',84053.0' Presque Isle (east of Rogers City) Table 4 (cont.) Recovery date 6VII55 4VIII55 3VII55 4VII55 4VII55 1VII55 2VIII55 13VII55 Days adrift 7 36 4 5 5 12 34 14 Miles traveled 4 4 Av. speed mph 0.02 14 12 11 71 13 88 0.15 0.10 0.09 0.24 0.26 **Still adrift when found. Table 5. Drift Bottle Data, Cruise Synoptic I Released Recovered Bottle Station No. Date Location Date Days Miles Average No. "Adrift" Covered Speed mph 3 2 29.6.54 Marine City, Mich., 30.6.54 1 28.8 1.2 on St. Clair River 4 2 29.6.54 Algonac, Mich., on 30.6.54 1 36.0 1.5 St. Clair River 144 2 29.6.54 Algonac, Mich., on 30.6.54 1 36.0 1.5 St. Clair River 133 3 29.6.54 43001.8 '82020.0' 2.7.54 3 12.1 0.16 135 3 29.6.54 43002.3',82016.0' 3.7.54 4 9.7 0.10 136 3 29.6.54 43 01.9, 82 18.0' 2.7.54 3 11.0 0.15 137 3 29.6.54 43001.9',82~18.0' 2.7.54 3 11.0 0.15 141 3 29.6.54 43001.9',82018.0' 2.7.54 3 11.0 0.15 142 3 29.6.54 43 01.9',82018.0' 2.7.54 3 11.0 0.15 125 4 29.6.54 4301.1 ',82025.8' 3.7.54 4 9.4 0.10 0 0 126 4 29.6.54 43001.1',82 25.8' 28.7.54 29 9.4 127 4 29.6.54 43001.1',82025.8' 3.7.54 4 9.4 0.10 33 5 29.6.54 43001.7' 82025.9' 4.7.54 5 4.0 0.03 35 5 29.6.54 43003.9',82025.7' 3.7.54 4 1.0 0.01 36 5 29.6.54 43001.7',82 25.9' 4.7.54 5 4.0 0.03 37 5 29.6.54 43 01.7',82 25.9' 4.7.54 5 4.0 0.03 40 5 29.6.54 43001.7',82 25.9' 4.7.54 5 4.0 0.03 41 5 29.6.54 43~01.7',82025.9' 4.7.54 5 4.0 0.03 42 5 29.6.54 43001.7',82 25.9' 4.7.54 5 4.0 0.03 122 6 29.6.54 43004.01.82027.0' 29.6.54 0 3.0 I --- - - - - - y -- -.. Table 5 (contd.) Released Recovered Bottle Station No. Date Location Date Days Miles Average No. "Adrift" Covered Speed mph 94 13 29.6.54 43055.0',81043.9' 2.7.54 3 12.2 0.17 106 18 29.6.54 43013.1',82001.0' 3.7.54 4 12.4 0.13 108 20 29.6.54 43044.6',81043.9' 1.7.54 2 9.1 0.19 109 20 29.6.54 43042.3',82 13.9' 30.6.54 1 6.5 0.27 110 20 29.6.54 43~42.3',82 13.9' 30.6.54 1 6.5 0.27 112 20 29.6.54 43042.3',82 13.9' 1.7.54 2 6.5 1199 22 29.6.54 43059.2',83010.5' 8.7.54 9 15.3 0.07 1200 22 29.6.54 43054.8',82 21.6' 10.7.54 11 19.7 0.08 1196 23 29.6.54 43055.9',82042.5' 24.7.54 25 28.0 0.05 1220 27 29.6.54 44002.0',83026.3' 4.7.54 5 4.3 0.04 1221 27 29.6.54 44002.0',83026.3' 4.7.54 5 4.3 0.04 1222 27 29.6.54 44002.0',83026.3' 4.7.54 5 4.3 0.04 1247 29 29.6.54 43058.8',83013.6' 8.7.54 9 28.9 0.13 1251 34 29.6.54 43055.7',82042.3' 5.7.54 6 11.2 0.08 563 35 29.6.54 44036.1',81017.1' 3.7.54 4 14.3 0.15 564 35 29.6.54 44031.8',81021.0' 2.7.54 3 12.9 0.18 565 35 29.6.54 43032.9',81 19.8' 3.7.54 4 13.4 0.14 Co> O Table 5 (contd.) Released Recovered Bottle Station No. No. 567 624 625 1280 1288 643 314 620 621 333 334 622 628 629 634 426 638 35 41 41 43 49 51 56 56 56 57 57 57 57 57 58 59 59 Date 29.6.54 29.6.54 29.6.54 29.6.54 29.6.54 29.6.54 29.6.54 28.6.54 28.6.54 29.6.54 29.6.54 28.6.54 28.6.54 28.6.54 28.6.54 29.6.54 28.6.54 Location 44034.6',81018.4' 44005.2',81044.9' o 0 44 07.4',81 41.9' 45004.3',83023.9' 44002.8',83001.6' 45033.7',82004.8' 440~55.7',81022.0' 45004.3',81030.9' 44052.8',81021.4' 44042.1',81016.7' 44041.7' 81017.8' 44044.1',81 18.2' 44052.8' 81 21.4' 44 47.9',81 17.3' 45015.6',81040.8' 44053.2',81021.3' 44029.2',80003.9' Date 30.6.54 9.7.54 5.7.54 23.7.54 17.7.54 9.10.54 4.8.54 6.9.54 26.7.54 8.8.54 31.7.54 11.8.54 28.7.54 6.7.54 10.7.54 29.8.54 15.7.54 Days "Adrift" 1 10 6 24 18 102 36 69 28 40 32 43 30 8 12 61 17 Miles Covered 13.7 28.2 24.8 11.0 79.8 2.5 35.4 24.7 38.0 42.3 42.0 39.1 30.4 36.5 4.9 40.0 128.0 Ave rage Speed mph 0.57 0.12 0.17 0.02 0.19 0.04 0.06 0.20 0.02 0.03 0.31 Table 5 (contd.) Released Recovered Bottle Station No. Date Location Date Days Miles Average No. "Adrift" Covered Speed mph 642 60 28.6.54 45018.7',81044.8' 27.8.54 59 12.6 0.01 346 64 28.6.54 45040.2',82018.7' 30.7.54 32 2.0 300 65 28.6.54 45035.7',82008.9' 14.10.54 117 14.0 316 68 28 6 54 44042.1',81 16.7' 10.7.54 12 96.4 0.33 (Rejected) 391 71 28.6.54 45048.4',82056.9' 13.7.54 15 8.0 0.02 1318 78 29.6.54 45056.0',83037.7' 11.7.54 12 6.0 0.02 1320 78 29.6.54 45056.0',83037.7' 11.7.54 12 6.0 0.02 1321 78 29.6.54 45056.0',83037.7' 11.7.54 12 6.0 0.02 1322 78 29.6.54 45~56.0',83~37.7' 11.7.54 12 6.0 0.02 1322 78 29.6.54 45056.0 '83037.7' 11.7.54 12 6.0 0.02 1359 86 29.6.54 45038.1',84016.4' 25.8.54 57 7.4 1361 86 29.6.54 45038.1 ',84016.4' 25.8.54 57 7.4 1384 87 29.6.54 45039.3' 84028.9' 7.7.54 8 7.0 1385 87 29.6.54 45039.2',84~18.8' 3.7.54 4 12.9 0.13 1387 87 29.6.54 45039.4',84019.4' 5.7.54 6 12.3 0.09 1353 88 29.6.54 45039.2',84022.8' 4.7.54 5 13.0 0.11 1354 88 29.6.54 45039.2',84022.6' 4.7.54 5 13.3 0.11 1355 88 29.6.54 45039.3',84022.3' 4.7.54 5 13.6 0.11 Table 5 (contd.) Released Recovered Bottle Station No. Date Location Date Days Miles Average No. "Adrift" Covered Speed mph 1368 89 29.6.54 45039.3 '84023.0' 2.7.54 3 16.4 0.23 1369 89 29.6.54 45 38.8',84024.7' 8.7.54 9 15.8 1370 89 29.6.54 45039.3',84023.0' 2.7.54 3 16.4 0.23 1371 89 29.6.54 45038.8',84024.7' 8.7.54 9 15.8 1372 89 29.6.54 45039.3',84023.0' 2.7.54 3 16.4 0.23 1380 90 29.6.54 45039.7',84025.4' 4.7.54 5 15.0 0.13 1382 90 29.6.54 45039.7',84025.4' 4.7.54 5 15.0 0.13 1363 91 29.6.54 45047.3',84026.1' 5.11.54 129 11.8 1364 91 29.6.54 45048.4,84030.0' 15.8.54 47 8.0 1365 91 29.6.54 45046.8',84023.2' 5.7.54 6 13.8 0.10 1343 92 29.6.54 45049.3',84036.3' 1.9.54 63 4.2 1345 92 29.6.54 45 47.6',84 27.3' 11.7.54 12 11.6 0.04 1351 93 29.6.54 45051.4',84~39.1' 12.7.54 13 3.2 0.01 1973 94 29.6.54 45024.3',83046.4' 15.7.54 17 48.0 0.12 1335 96 29.6.54 45021.4',83029.6' 10.7.54 11 53.4 0.20 1374 97 29.6.54 45029.5',83059.0' 4.7.54 5 26.6 0.21 1375 97 29.6.54 45029.7',83058.0' 7.7.54 8 24.7 1338 98 29.6.54 45027.2',83052.3' 6.7.54 7 29.3 0.17 1339 98 29.6.54 45029.6',83057.4' 5.7.54 6 24.0 0.17 Table 6. Drift bottle data, Cruise Synoptic VI, 9 August 1955. Release Recovery Recovery Days Miles Av. speed Bottle No. station location date adrift traveled mph 2801 101 41055.5',86035.5' 14VIII55 5 20 0.17 2144 111 43040.0',86031.9' - - 22 -2143 111 43039.3',86032.4' 20VIII55 11 20 0.08 2142 111 43042.0',86030.9' 19VIII55 10 25 0.10 2073 116 43046.0',86026.9' 12VIII55 3 2 2075 116 43040.3',86032.1' 13VIII55 4 9 0.09 2066 117 43003.3',86014.3' 30VIII55 21 59 0.12 3918 117 43041.7',86030.9' 20VIII55 11 13 2403 121 45000.4',87010.0' 13VIII55 4 17 0.18 2405 121 44057.0 ',87011.0' 17VIII55 8 14 2404 121 44057.0',87011.0' i7V11155 8 14 3865 124 43058.9',86028.0' 19XI55 71 28 0.02 2413 125 44012.2',86022.1' 21VIII55 12 6 0.02 2305 126 44033.7', 86013.6' 17VIII55 8 9 0.05 2318 130 45024.8' 86056.2' 15VIII55 6 16 0.11,,- >.o. 17 A. A' Q f 01 7TTCC 2 iA n.rn 2317 130 45~24.0',86~50.8 12V III55 3 14 0.20 2319 130 45024.0',86~51.0' 17VIII55 8 14 2314 131A* 45041.2',86040.6' 6XI55 58 25 0.02 3859 139 45019.3',85015.5' 10VIII55 1 4 0.17 3846 139 45018.9',85016.6' 1OVIII55 1 4 0.17 3831 141 45003.7',85043.5' 23VIII55 14 38 0.11 3795 141 45018.8',85016.9' 24VIII55 15 29 3837 145 near Cheboygan, Mich. 21VIII55 12 11 3741 145 " " " 21VIII55 12 11 3849 145 45044.2', 84035.1' - 8 3813 145 45043.8', 84036.5' 13VIII55 4 7 0.07 3729 145 45043.8', 84036.5' 12VIII55 3 7 0.10 3825 145 45043.8', 84036.5' - 7 *At Fisherman Shoal buoy, Washington Island. CO Wok. w~ Table 6 (cont.) Release Recovery Recovery Days Miles Av. speed Bottle No. station location date adrift traveled mph 3777 148A 46002.3 ',85006.9' 1OVIII55 1 2 0.08 3861 148A 46002.3, 85006.9' 1OVIII55 1 2 0.08 3860 148A 46002.3',85006.9' 10VIII55 1 2 0.08 3801 148A 46002.3', 85006.9' OVIII55 1 2 0.08 3789 148A 46002.3',85006.9' 1OVIII55 1 2 0.08 3799 149 45041.3',84057.7' 18VIII55 9 20 3776 149 45036.4',85005.0' 22VIII55 13 23 3823 149 45~36.4', 85005.0' 16VIII55 7 23 0.14 3811 149 45039.1',85001.3' 12VIII55 3 21 0.30 3812 150 45008.9', 85033.7' 25VIII55 16 54 0.14 3848 150 45016.2',85022.4' 28XI55 80 42 3764 151 45038.0', 85~04.2' 12VIII55 3 13 0.18 3751 151 45038.0', 85004.2' 12VIII55 3 13 0.18 3787 151 45038.0', 85004.2' 12VIII55 3 13 0.18 Table 7. Drift bottle data, Cruise Synoptic VI, 10 August 1955. Release Recovery Recovery Days Miles Av. speed Bottle No. station location date adrift traveled mph 2196 101 41058.8',86033.5' 16VIII55 6 25 0.17 2199 101 41044.1',86053.2' 11VIII55 1 2 0.08 2197 101 41054.0', 86036.9' 15VIII55 5 19 0.16 2198 101 41044.2', 86052.6' 12VIII55 2 3 0.06 2683 102 41044.2',86052.6' 18VIII55 8 21 2847 102 41048.1',86044.3' 16VIII55 6 25 0.17 2850 102 41045.2',86049.8' 17VIII55 7 22 0.13 2848 102 41055.2', 86035.3' 19VIII55 9 30 0.14 2849 102 42000.9', 86032.6' 22VIII55 12 33 2739 104 42000.7', 87009.6' 12VIII55 2 21 0.44 2736 104 41059.6',87009.0' 12VIII55 2 22 0.46 2740 104 42~02.6',87~10.0' 12VIII55 2 19 0.40 2207 105 42007.1',87013.8' 13VIII55 3 17 0.24 2774 111 43058.9',86028.1' 22VIII55 12 44 0.15 2154 112 43043.8',86016.1' 30VIII55 20 36 0.08 2167 114 Drummond Island 13XI55 95 300 2189 115 43001.3',87056.4' 11 VIII55 1 2 0.08 3958 116 43046.0', 86026.8' 12VIII55 2 1 3945 116 43045.3',86027.3' 11VIII55 1 2 0.08 2380 121 44043.2',87020.1' 23VIII55 13 6 2377 121 44045.1',87019.7' 15VIII55 5 3 0.03 2373 124 43~49.8',86025.6' 21VIII55 11 39 0.15 2370 125 44~27.1',86~15.3' 19VIII55 9 9 0.04 3769 139 45019.0', 85017.1' 5XI55 87 3 3781 139 45~17.8',85~19.4' 13VIII55 3 4 0.06 3841 139 45~17.8 ',85~19.4' 13VIII55 3 4 0.06 3854 139 45017.8',85019.4' 13VIII55 3 4 0.06 3805 139 45017.1',85020.7' 12VIII55 2 5 0.10 c1 Table 7. (cont) v Release Recovery Recovery Days Miles Av. speed Bottle No. station location date adrift traveled mph 2891 140 45026.4',85010.6' 23X55 74 19 2892 140 45~27.4',84~59.0' 23VIII55 13 28 0.09 2786 140 45030.1',85014.5' 22VIII55 12 17 0.06 2880 141 45~04.2', 85035.0' 19VIII55 9 38 0.18 2876 141 45005.2',85035.8' 19VIII55 9 37 0.17 2871 141 45021.1',85012.4' 15X55 66 18 2862 143 45044.8',85034.3' 23VIII55 13 26 0.08 3782 144 45047.0', 85030.3' 25VIII55 15 35 0.10 --- Table 8. Drift Bottle Data, Cruise Synoptic II Released Station No. Date Recovered Bottle No. Location 48 1 50 1 27.7.54 Belle River on S. shore Lake St. Clair 27.7.54 Stoney Point on S. shore Lake St. Clair 293 294 296 297 2 2 2 2 27.7.54 27.7.54 27.7.54 27.7.54 Port Huron, Mich. Port Huron, Mich. Port Huron, Mich. Port Huron, Mich. 69 3 72 3 27.7.54 2 mi S of Courtright, Ont. 27.7.54 Port Lambton, Ont. 27.7.54 43050.5',81044.0' 27.7.54 43051.2',81044.0' Date 6.8.54 4.8.54 30.7.54 30.7.54 28.7.54 29.7.54 10.8.54 27.12.54 30.7.54 30.7.54 31.7.54 30.7.54 5.8.54 8.8.54 30.7.54 30.7.54 10.8.54 29.7.54 Days "Adrift" 10 8 3 3 1 2 Miles Covered 54 55 11.0 11.0 11.0 11.0 Average Speed mph 0.24 0.28 0.46 101 102 159 160 161 162 195 197 947 879 13 13 18 18 18 18 20 20 27 D29 27.7.54 27.7.54 27.7.54 27.7.54 43020.4',81 044.4' 43O20.0',81 44.7, 43021.1',81043.9' 43020.4',81044.4' 14 152 3 3 4 3 9 12 3 3 14 2 31.0 41.0 6.4 7.0 5.4 4.9 5.0 5.4 0.09 0.09 0.10 0.07 0.22 0.22 0.09 0.04 27.7.54 43049.0',81043.9' 27.7.54 43049.0',81 43.9' 27.7.54 44002.7',82052.7' 27.7.54 44015.0',83026.9' 14.5 14.5 31.9 2.0 -23 Table 8 (contd.) Released Recovered Bottle Station No. Date Location Date Days Miles Average No. "Adrift" Covered Speed mph 548 58 27.7.54 Flowerpot Island 1.9.54 35 8.3 0.01 429 61 27.7.54 45036.6',82011.0' 25.8.54 29 7.8 0.01 431 61 27.7.54 45036.6',82 11.0' 25.8.54 29 7.8 0.01 438 63 27.7.54 45040.3',82019.4' 1.8.54 5 7.4 0.06 443 64 27.7.54 45040.3',82018.7' 27.8.54 31 2.3 444 64 27.7.54 45 40.1',82 19.2' 14.8.54 18 2.5 1934 79 27.7.54 45056.7',83059.3' 22.10.54 87 6.0 1936 79 27.7.54 45058.2',83052.9' 17.8.54 21 2.6 1937 79 27.7.54 45 58.2',83 52.9' 17.8.54 21 2.6 1990 79 27.7.54 45052.9',83052.2' 5.8.54 9 2.2 0.01 1992 79 27.7.54 45052.9',83052.2' 5.8.54 9 2.2 0.01 1788 87 27.7.54 45049.0',84034.9' 8.8.54 12 8.4 0.03 1789 87 27.7.54 45049.0',84034.9' 8.8.54 12 8.4 0.03 1790 87 27.7.54 45049.0',84 34.9' 8.8.54 12 8.4 0.03 o o 1792 87 27.7.54 45048.2',84 34.8' 7.8.54 11 7.7 0.03 1748 88 27.7.54 45052.6',84038.0' 29.7.54 2 7.3 0.15 1749 88 27.7.54 45051.4',84038.7' 1.8.54 5 6.3 1750 88 27.7.54 45052.6',84038.0' 29.7.54 2 7.3 0.15 1751 88 27.7.54 45052.6',84038.0' 29.7.54 2 7.3 0.15 Table 8 (contd.) Released Bottle Station No. Date No. 1813 89 27.7.5, 1816 89 27.7.5, 1784 90 27.7.5, 1797 91 27.7.5, 1704 93 27.7.5, 1705 93 27.7.5, 1739 95 27.7.5, 1 742 95 27.7.5, 1709 96 27.7.5, 1844 98 27.7.5, 1846 98 27.7.5, Recovered 4 4 4 4 4 4 4 4 4 4 4 Location 45042.2',84~33.8' 45041.0',84032.1' 45057.2',84038.0' 45049.3',84038.0' 45058.1',84030.9' 45058.1',84 30.9' 45057.3',84 21.2' 45 59.7',84021.6' 45019.2',83027.9' 45046.3',84~31.9' 45029.6',83057.6' Date 4.8.54 3.8.54 1.10.54 2.10.54 1.8.54 6.8.54 3.9.54 10.8.54 22.8.54 3.8.54 1.8.54 Days "Adrift" 8 7 66 67 5 10 37 14 26 7 5 Miles Covered 9.0 11.0 10.5 2.6 8.0 8.0 4.8 7.3 56.1 10.1 23.8 Average Speed mph 0.07 0.07 0.02 0.09 0.06 0.20 co Table 9. Drift Bottle Data, Cruise Synoptic II Cn ak --- Released Bottle Station No. Date No. Recovered Location Date 1034 1035 1036 1037 728 1145 1049 1645 1646 1642 26 213 1 1 1 1 3 6 A7 B7 B7 12 17 18 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 Sombra, Ont. on St. Clair River Stag Island Lighthouse (St. Clair River?) Syne Carte Point (St. Clair River) Chenal Ecarte, W. of Wallaceburg, Ont. at mouth Pine River in St. Clair River 43009.8t,82030.8' near Tecumseh, Ont. 43031.2,82034.8' 43030.2',82034.6' 43007.8',82029.7t 43~14.4',82006.2' 43013.2',8200.9' 1.9.54 29.8.54 29.8.54 28.8.54 29.8.54 30.8.54 5.9.54 29.8.54 30.8.54 28.8.54 2.9.54 17.9.54 Days "Adrift" 7 4 4 4 4 5 11 4 5 3 8 23 Miles Covered 25 13 (?30) 36 Average Speed mph 0.15 0.1 3 recovery poj not identifie 0.50 nt I 18 8.5 65 21.5 23 12.5 13.5 13.5 0.07 0.24 0.22 0.18 0.07 Table 9 (contd.) Released Station No. Date Recovered Bottle No. 1776 1777 1869 1871 1872 848 849 788 818 819 820 821 822 814 815 816 1424 1013 1581 Location Date 34 34 34 34 34 43 43 48 88 88 88 88 88 89 89 89 91 96 98 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 25.8.54 44001.6',82047.8' 44001.9',82048.2' 43~56.6',82~42.8' 44001.0',82047.2' 44 01.9',82 48.2' 44055.6',83~55.3' 45000.5',83 56.3' 45021.2',83033.0' 4541.8',84031.5' 45040.7',8431.0' 45040.7',84031.0' 45040.7',84031.0' 45 40.7',84 031.0 45044.6',84039.6' 45046.0',84042.6' 45 46.0',84042.6' 45~53.7',84 49.0' 45~53.6',84~24.9' 45033.4',84007.8' 28.8.54 28.8.54 26.8.54 30.8.54 26.8.54 31.8.54 30.8.54 6.9.54 26.8.54 26.8.54 26.8.54 26.8.54 26.8.54 1.9.54 2.9.54 17.9.54 31.8.54 29.8.54 19.9.54 Days "Adrift" 3 3 1 5 1 6 5 12 1 1 1 1 1 7 8 23 6 4 25 Miles Covered 4 4 10 5 4 6 9.5 28 5 5.7 5.7 5.7 5.7 3.2 1.5 1.5 13 5.5 14.5 Average Speed mph 0.42 0.17 0.07 0.20 0.24 0.24 0.24 0.24 0.09 0.06 --