vv~• ,,. ........ '-./ \. \ \niti&l ..... , ~ ~ ~ .Fi.\e_ .......-········ C. C. I. W. LIBRARY MANUSCRIPT No. REPORT SERIES 4 ~ {3tJ.~t-t~tt4eetttJ.~t- ttJ. t~e Oee4~t-tJ.fJ't4ft~'f tJ.I ~eedd-tJ.~t- ~a~~ F. G . BARBER Morine Sciences Branch 1967 Deportment of c[nergy, Mines and Resources, Ottowa . A CONTRIBUTION TO THE OCEANOGRAPHY OF HUDSON BAY F. G. Barber \ I I 1967 .. ROGER DUHAMEL, F.R.S.C. QUEEN'S PRINTER AND CONTROLLER OF STATIONERY OTTAWA, 1967 , • CONTENTS PAGE 1. INTRODUCTION •......•.....••.••...•.•••.... , . • . • . 1 2. DESCRIPTION OF THE DISTRIBUTION OF PROPERTIES 4 FACTORS WHICH DETERMINE THE DISTRIBUTIONS 20 \ 3. ................ 3. 1 Net current and depth • • • • • • • • • • • • • • • • • • . • • . • • • • • • • • • • • • • • • 20 3. 2 Tidal streams and tidal mixing. • • • . • • • • • • • • • • • • • • • • • • • • • • • . 23 3. 3 Exchange of energy at the surface ••• • • • • • • • • • • • • • • • • • • • . • • • 26 3. 4 Ice cover and the surface mixed layer • • • • . • • • • • • • • • • .. • • • • 2 7 3. 5 Fresh water from run-off . 28 3. 6 Sllrface wind . .. 31 4. DISCUSSION . • . • . • . • . • . 32 4.1 A fresh water budget ................................ -..... 32 4.2 A volume budget ...•........................•....•........ 36 4.3 The probable near-surface salinity distribution in winter •••••• 38 4.4 The influence of ice cover in the 1961 season ••••••••..•..... 40 4.5 A preliminary heat budget of the sea in the vicinity of Churchill for 19 61 . 45 4.51 Short-wave radiation from sun and sky •••••••••••• 47 4.52 Reflected short-wave radiation •••••••.•.•.•••.•• 47 4.53 Effective long-wave back radiation .•.••••••.•..•. 48 4.54 Evaporation . .................................. 48 4.55 Conduction of sensible heat 49 4.56 Precipitation ............ ~ .................... 50 4.57 Net of the radiative and flux terms •••.••.••••.••• 50 4.58 Heat storage and advection ••••••••••••..•••••••. 52 4.59 Other aspects .......... : .........•............. 53 4. 6 A model . 54 4. 7 Suggestions for future work • • • • • • • . • . • • • • . • • • . • • • • • • • • • . • 63 5. SUMMARY . • . • . • • . • . • • . • . ... • • . 63 6. ACKNOWLEDGEMENTS ........................................... 64 7. REFERENCES ..........................................• ......... 64 .. Foxe Basin Foxe Channel <0 VNottingham I. Coats '0 Digges Is... """" Manseii.Q Ottawa Is... ,11 , HUDSON BAY \ 0\ ~ ... i Belcher Is. ,jj~t1 · ""//f(Omarollu~ Sd goo Place names in the Hudson Bay region. 1. INTRODUCTION It is the intention to provide in this work a description of the distribution of certain of the phy~ical features and properties of the water of Hudson Bay,. and to remark on the more important processes which likely determine these distributions. The region is still only imperfectly known so that much of the discussion regarding ,, processes is based on experience and understanding gained in study of other regions, both coastal and oceanic. It is to be expected however that Hudson Bay would exhibit features quite unique, for it is notable not only for a general shallowness relative to the total area, but also for the continental location, the existence of a winter ice cover, and the marked amplification, in certain areas, of the oceanic tide. The integrated effect of these and other conditions leads to the observed features out of which under­ standing evolves. At present this is mainly qualitative and, in some important aspects, also speculative. As is apparent from the description in later sections, differences of density under most conditions occurring in Hudson Bay are determined by differences of salinity; temperature plays a secondary role as the range is relatively small. Also the lower limit of the range is frequently close to the freezing point. This provides a partial filter with respect to certain data in that their correctness is suspect if they are much below the freezing point. An example is the temperature data reported by Hachey (19 31 a),-which include a number of unrealistically low values. Hachey (1931a) provided a summary of the expeditions and workers in Hudson Bay prior to the 1930 Hudson Bay Fisheries Expedition in "Loubyrne" (Hachey, 1931b), and remarked therein, "the first known attempt to determine the water temperatures and densities at the various depths was made by Beauchemin in 1929". In this, stations were occupied in Hudson Strait, in Hudson Bay along the route to the port of Churchill, and in Churchill Harbour. A generally similar series of observations was made in the navigation season of each of the years 1930 and 1931; the data for the three years have been reported (Anon., 1931a; 1931b; 1932), and the vessel in which the surveys were . conducted, the "Acadia", has been described (Anon., 1964c). Examination of the above reports and the relevant field books, as well as discussions with Mr. J. A. Deveault, who was a member of the "Acadia" survey staff during each of the three seasons and who participated in the sampling program, have indicated that two protected thermometers were attached to each reversing bottle, and that a cast consisted of a lowering of one bottle. "----the sNp was equipped with the latest pattern of Nansen Stopcock reversing deep-sea water bottles of 1 1/2 litre capacity, each bottle being equipped with two Negretti and Zambra reversing deep-sea thermometers, registering from -2 to 25° Centigrade: each thermo­ meter bearing a certificate from the National Physical Testing Laboratory. Negretti and Z ambra hydrometers were used to obtain the densities, the usual practice at 60° Fahrenheit being closely followed." (from Anon., 1931a, p. 112). 2 Table I. A tabulation of the available material, much of which was examtlled in the preparation of this work, indicating the year obtained, name of ship, Canadian Reference Number, and at least one reference. Most of the material is available in the record~ of the Canadian Oceanographic Data Centre and is listed in the cone index (Anon.' 1965, a). An asterisk in the last column indicates that the - publication is a data report or contains data in tabular form. Year Ship CRN Reference 1929 "Acadia" 24 Anon., 1931, a* 1930 " Loubyrne" 29 Hachey, 1931, a* 1930 "Acadia" 32 Anon., 1931, b* 1931 do 35 Anon. , 1932* 1948 "Haida" 100 Bailey et al. 1951 and Dunbar, 1958* 1953 "Cal anus" 193 Grainger et al. 1956 1954 do 186 do 1955 "Labrador" 203 Campbell, 1959 1956 do 211 do 1956 do 219 do 1955 "Calanus" Grainger et al. 1959 1958 do do 1958 do 320 Grainger, 1960* 1959 do 321 do 1959 "Labrador" 323 1961 "Cal anus" 354 Anon. , 1964, b* 1961 "Theta" 337 Anon. , 1964, a* l 1962 "John A. MacDonald" 359 Anon., 1966* 3 In the available records only the corrected value for each thermometer is shown so that it was not possible to check the corrections to the temperature data, but the material does appear to be free of values which, at the present level of our under­ standing of the region, might be considered anomalous*. The distribution of temperature at 75m depth as obtained from these obs.ervations is shown in a figure and discussed here in the appropriate section; the density values have not been utilized. Also it appears that two samples were drawn from each water bottle and carefully stored for analysis ashore which was to include some form of chemical determination. No record of this has been found. With regard to the work of "Acadia" mention should be made of a program of drift-bottle releases during the autumn of 1929 on the return voyage between Churchill and eastern Hudson Strait (Anon., 1931a). Eighteen bottles were released but there is no record of any returns (Dr. H. B. Hachey, personal communication). The first determination of the salinity of the water of Hudson Bay was that reported by Hachey (1931a) in a discussion of the "Loubyrne" data. This indicated a relatively low level of salinity generally, which in part led Bailey et al. (1951) to a comparison with the 1948 "Haida" observations and to conjecture concerning an increase in the influence of Atlantic water in Hudson Bay. The data utilized in the present work include those obtained in the vessels men~ioned above as well as those obtained in the vessels listed in Table I. With regard to sub-surface temperature and salinity data obtained through shipborne survey, it is believed that the listing is complete. A useful group of observations in Hudson Bay is that carried out in "Calanus"; the extent of these observations to 1958 has been described in three station lists (Grainger, 1954; Grainger et al., 1956; 1959), and a summary of the available results to 1955 was provided by Dunbar (1956). Extensive observations in more northerly portions of the system including Hudson strait were made in 1955, 1956, and 1959 in the icebreaker "Labrador". Part of this material has been utilized in a number of reports including those of Campbell et al. (1956; 1958) and Campbell (1958; 1959; 1964). Most of the observations described here were made in 1961 in the motor vessels "Calanus" and "Theta" and in 1962 in the Department of Transport icebreaker "John A. MacDonald". The program of "Calanus" and "Theta" included observations for biological, geological, and geophysical as well as physical oceanographic obser­ vations. The latter have been reported in data record form (Anon., 1964a; b), atlas form (Barber et al., 1964), and discussions of most of the other observations have been given by Grainger (1963), Hood (1964; 1966), Leslie (1963; 1964; 1965), Leslie et al. (1965), and Barber (in review). The survey of 1962 comprised one of the most wide-ranging shipborne surveys conducted in the Canadian Arctic in one season. stations were occupied from McClure Strait on the west to Nansen Sound in the north *The cold water (to -1. 8°C) to 541m noted at "Acadia" station 19 on October 30, 1929 in eastern Hudson Strait is of interest as no other such occurrence has been recorded although a number of stations have been occupied since. as well as in Hudson Strait and in Hudson Bay where a number of the positions occupied in 1961 were re-occupied.