FISHERIES RESEARCH BOARD OF CANADA

MANUSCRIPT REPORT SERIES

(OCEANOGRAPHIC and LIMNOLOGICAL)

No. •

TITLE

ICE STUDIES OF THE ATLANTIC OCEANOGRAPHIC GROUP

AUTHORSHIP

N.J. Campbell & L.M. Lauzier

Establishment

ATLANTIC OCEANOGRAPHIC GROUP

Dated March 4, 1960 Programmed by THE CANADIAN COMMITTEE ON OCEANOGRAPHY Preface

This report contains a short summary of the ice studies carried out by the Atlantic Oceanographic Group, Fisheries Research Board of Canada over the oast five years. The purpose of the report is to table the interests,, objectives, results, and accomplishments of the Arctic and Gulf of St. Lawrence oceanographic operations of the Atlantic Oceanographic Group. General recommendations are included as to how these studies might be furthered to meet national requirements. The authors are indebted to all the member ar;encies of the Canadian Committee on Oceanography who have supported and contributed to these studies.

N. J, Campbell

L. M. Lauzier. Ice Studies of the Atlantic Oceanographic Group in Arctic Waters by N. J. Campbell

Introduction

Since the first voyage of FMCS "Labrador", now CGS "Labrador", to the Arctic in 1954, ice studies have been included in the arctic oceanographic investigations of the Atlantic Oceanographic Group. The reasons why oceanographers are concerned about sea ice problems stem from the fact that ship operations must first be successfully carried out before any oceanographic observations can be made. Once the observations are made, they can only be completely analysed and studied by taking into consideration the ice conditions for the area in question. Ice, therefore, plays a significant role in Arctic Oceanography, it affects planning, obstructs field operations, and influences oceanographic results. It is another oceanographic parameter that must be contended with in Arctic Waters.

Purpose

The purpose of the arctic sea ice studies undertaken by the Atlantic Oceanographic Group were principally: (a) to assure an accessible region of study (b) to gain a better understanding of oceanographic conditions. 2

(c) to determine cause and effect relationships between water characteristics and ice conditions, (d) to collect data for the ice forecast centre of the United States Navy Hydrograohic Office,

Interests

(a) Field operations are of definite interest to the oceanographer, since he must be acquainted with the practical problems of reaching a designated area and the problems associated with taking oceanographic observations in ice infested waters. The oceanographer, therefore, must have the following information available before, during, and after an arctic cruise: (1) Yearly long-range ice forecasts to guide initial planning, (2) Short-range forecasts while oceanographic surveys are being carried out (3) Aircraft reconnaissance on a need-to-know basis. The reasons for these requirements are numerous and can be simply summed up by stating that without adequate ice forecasts one is faced with the likelihood of an unsuccessful field venture and subsequent disappointing scientific returns. Predictions, forecasts, and reconnaissance, items (1), (2), and (3), must be checked against one another and correlated with ice observations and oceanographic and meteorological results and observations. The accuracy and dependability of the forecasts depend, to a large extent, on the oceanographic coverage and observations carried out the year before. The corollary is equally significant to oceanography because without dependable and reliable ice information a precise interpretation of the oceanographic data is exceedingly difficult. Ice studies must go further than satisfying immediate needs, it must also provide seasonal information and the history of ice conditions.

(b) The distribution, concentration and movement of ice is of prime interest to oceanographers since information on currents and movement of ice by wind can be gained by studies of ice movement. It is possible, for example, to separate wind and water movements by careful studies of the size distribution of ice floes. It is also possible to learn something of the turbulence of waters by close observations of the behaviour of ice. (c) Forecasting of ice conditions has been carried out at the Atlantic Oceanographic Group for the Gulf of St. Lawrence, but for Arctic waters we co-operated with the U.S.N.H.O. in a co-ordinated,program of oceanographic research to provide data for determining ice potentials and forecasts for the following year. The program constituted one of mutual benefit and of continuing interest, and permitted exchange of field personnel with ice forecasters from U.S.N.H.O.

Results

(a) The oceanographic teams on "Labrador" obtained or made copies of all ice data pertinent to the cruise. This information was supplemented by particular studies of dirt concentration, types of debris strewn on the ice, water temperatures, and turbulence. The records were used extensively in the analysis of oceanographic conditions in Hudson Strait, northern Hudson Bay, Foxe Channel, Foxe Basin, Gulf of Boothia, Prince Regent Inlet, Barrow Strait, Wellington Channel, Franklin Strait, and Lancaster Sound. (b) Other aspects of ice conditions were studied mainly to gain information on water and ice movement. The methods involved the following studies: (1) Time-lapse radar photography, (2) Cine-camera records of ice behaviour in turbulent waters, (3) Dye marking of ice floes, (4) Aerial photography. All of the above techniques were employed, at times being carried out when the ship was performing other duties. Items (1) and (2) proved practical and extremely useful, (3) was attempted in various ways with a wide variety of dyes, but was still in the experimental stage when the program could no longer be continued owing to other studies, (4) was carried out and the data partially analysed, but as a result of inexperience, the experiment was poorly undertaken. A fifth method of study involving time-lapse cine-records was planned, but time did not permit undertaking the work. (c) Ice physics constituted one phase of the summer program in 1956 when AOG teamed with Dr, E. M. Little of United States Navy Electronics Laboratory, San Diego, California, to conduct measurements and studies of ice hardness, conductivity, crystal structure, shear and tensile strengths. (d) The distribution of Foxe Basin ice was a subject of study in 1955 and 1956 and involved a program of ice studies, oceanography, and submarine geology. The results indicated that the perennial "dirty" character of the ice could be attributed to the suspension freezing of bottom sediments in the ice. (e) The study of the discoloration of Foxe Basin ice is being followed up by another study related to ice growth that involves the formation of unusually cold high salinity water. (f) Studies on the distribution of the "dirty ice" were carried out in 1955 and 1956 in Hudson Bay and Hudson Strait in an attempt to trace the movements of water from Foxe Channel. The work requires the use of an aircraft and the studies, consequently, cannot be considered as complete.

Recommendations

There is an oceanographic need for the following-- (1) Long and short range forecasts of arctic ice conditions; aerial surveys on a need-to-know basis while an oceanographic cruise is in operation. (2) Co-operative research programs involving ice observers, meteorologists, and oceanographers ° (3) Establishment of a monitoring network of coastal and offshore oceanographic stations for studies of ice and oceanographic conditions.

(4) Establishment of regular aerial observation and photographic flights to include: (i) studies of winter "open water pools" (ii) iceberg distribution and movement. (5) Aerial photographic observations of surface currents. (6) Aerial reconnaissance of the distribution of "dirty" Foxe Basin ice in Hudson Bay, Hudson Strait, and off the Labrador

Coast. (7) Further experiments on ice marking techniques.

(8) The printing and distribution of an Ice Atlas showing the seasonal histories of ice distribution and concentration. (9) Winter oceanographic surveys. (10) Experiments of either a mechanical or hydraulic nature to determine the feasibility of fending ice off the side of a ship while an oceanographic station is being occupied. -7

References

Bailey, W. B. 1957. Oceanographic features of the Canadian Archipelago j. Fish. Res. Bd. Canada, 14(5), pp 731-769. Campbell, N. J. and A. E. Collin MS 1956.A preliminary report on some oceanographic features of Foxe Basin. Fish. Res, Bd. Canada, MS Rept. Biol. Sta.

No. 613, 42 PP. Campbell, N. J. and A. E. Collin. 1958. The discoloration of Foxe Basin ice. J. Fish. Res. Bd. Canada 15(6), pp 1175-1188. Campbell, N. J. MS 1958.The Oceanography of Hudson Strait Fish. hes. Bd. Canada, MS Report No. 12, Oceanographic and Limnological Series, 6Opp. Campbell, N. J. MS 1959. Some oceanographic features of Northern Hudson Bay s Foxe Channel, and Hudson Strait. Fish. Res. Bd. Canada, MS Report No. 46,

Oceanographic and Limnological Series 29 pp. Campbell, N. J. 1959. The origin of cold high salinity water in Foxe Basin and Foxe Channel. Abstract First International Symposium on Arctic Geology. Canadian Oil and Gas Industries. December. Collin, A. E. MS 1958. An oceanographic study of Prince Regent Inlet, the Gulf of Boothia, and adjacent waters. Fish. Res. Bd. Canada, MS Report No. 13,

Oceanographic and Limnological Series, 46 pp. Ice Studies of the Atlantic Oceanographic Group in the. Gulf of St. Lawrence by L. M. Lauzier

Introduction

The full understanding of oceanographic conditions: in the Gulf of St. Lawrence have long been seriously hampered by the lack of observations during the winter season. In February and March 1956 and 1957, winter surveys were carried out in this area from H.M.C.S. "Labrador". During the surveys, air cover was provided by the RCAF to determine ice distribution and movement.

Purpose

The purpose of the winter surveys was to observe: (a) the horizontal and vertical distribution of temperature and salinity throughout the Gulf and the Estuary, (b) the nature and extent of ice coverage and ice movements, distinguishing in particular between river, sea, and Labrador ice, (c) the disposition and volume transport of the Gaspe and Cape Breton Currents, (d) the contribution of the Gaspe and Cape Breton Currents to the formation and transport of ice.

Interests

Ice studies in the Gulf are related to the following points of interest: (a) the formation of ice as an oceanographic phenomenon, (b) the effects of winter cooling and ice coverage on the formation and distribution of the cold water layer in the Gulf.

Results

a) The winter data used in conjunction with that of the previous autumn made possible a preliminary study of the heat budget in the northwest sector of the Gulf. Ice potentials were computed for the winter seasons 19551956 and 1956-1957. The results showed some dependence of the nature and extent of ice upon oceanographic and meteorological conditions. Ice conditions were light in 1956 and heavy in 1957. The heavy ice conditions in the latter year were related to relatively high ice potentials and low air temperatures at the beginning of the winter. b) Ice distribution observed at the time of the 1956 survey was, to a certain extent s controlled by oceanographic conditions. Areas of open water were found to be generally associated with higher temperatures and higher salinities. c) Winter observations in 1956 and 1957 indicated that cooling at the surface was greater in 1957 than in 1956. However, the thickness of the mixed layer was greater in 1956 than in 1957. In balancing the heat budget, there were indications that the addition of relatively warm waters to the area via the deep layer, was responsible for slowing down the process of cooling in 1957. The formation of the cold-water layer in the Gulf is related to - 10 - the cooling of the upper layers and to the production of the mixed layer in winter. In turn, the production of the mixed layer is greatly influenced by the amount of heat brought into or carried away from the region by the deep currents or the processes of mixing. The volume of the cold-water layer, observed in the Gulf from spring to autumn, varies from year to year depending on the amount of cooling in the upper layers during the previous winter and also on the heat transport of the deep layers. d) A preliminary study of ice-bound phytoplankton was undertaken in the southern part of the Gulf in 1957. The results showed that more than 40 species were Present in the samples collected in the Cape Breton area. The diatoms and other forms identified were comAdered to be of particular importance as a source of food for planktonic crustaceans. The ice-bound phytoplankton could be considered as food storage for the herbivorous spring blooms.

e) The general distribution of ice and iceb e rgs in the entrances to the Gulf of St. Lawrence and along the south coast of Newfoundland was compiled at AOG. This compilation was undertaken in order to bring together information pertaining to currents or general circulation and average ice conditions. f) Ice conditions as affecting oceanographic conditions in the upper layers during the spring season were found to be a useful tool for estimating climatic fluctuations and their effects on certain fisheries, such as herring, in the Magdalen Islands, Que. - 11

Recommendations

1. The need for sound ice forecasting for the Gulf and the Estuary of St. Lawrence requires the co-operation of ice forecasters, oceanographers, and meteorologists in a study of the formation, growth, and movement of ice. Autumn and winter oceanographic observations are of the utmost importance. 2. Winter and spring oceanographic observations are required to study the formation and distribution of the cold water layer. The distribution and variation of the cold-water layer in the Gulf from year to year, as the result of winter cooling, are generally some of the controlling factors of the fisheries in the Gulf. 12

References

Bailey, W. B. and L. M. Lauzier MS 1956. Incidence of ice and icebergs in the entrances to the Gulf of St. Lawrence and along the south coast of Newfoundland. Fish. Res. Bd. Canada, MS Rept. (Biol. Sta.) No. 614, 26 pp. Lauzier, L. M. MS 1957. A preliminary report on the winter oceanographic survey in the Gulf of St. Lawrence, 1956, Fish. Res, Bd. Canada, MS Report No. 3, Oceanographic and Limnological Series 19 pp. Lauzier, L. M. MS 1958. Some aspects of oceanographic conditions in the Gulf of St. Lawrence from autumn 1956 to spring 1957. Fish. Res. Bd. Canada, MS Report No.9, Oceanographic and Limnological

Series 18 pp. Lauzier, L. M. and R. D. Graham MS 1958. Computation of ice potentials and heat budget in the Gulf of St. Lawrence. Fish. Res. Bd. Canada, MS Report No.11, Oceanographic and Limnological Series 7 pp.