Measurements of the tide level, current, temperature and salinity of McMurdo Sound and examination of the biological biomass in the water column

A measurement of the tides and currents in McMurdo Sound was conducted over several seasons. Current measurements were first made in McMurdo Sound by Hodgson (1907) during the stay of the Discovery in Winter Quarters Bay in 1902-1903. Further measurements were made in the 1950s with the establishment of both McMurdo Station and Scott Base. Current measurements made in the late 1950s and early 1960s are described in Tressler and Ommundsen, 1962, Gilmour et al., 1962, Gilmour, 1963 and Littlepage, 1965. In the 1970-71 field season, a tide gauge was established at McMurdo Station on the rock pier built for the inlet and outlet to the nuclear power plant at the time. Six weeks of records were obtained from this gauge. Holes were drilled in the fast ice and measurements were made of the current, standard temperature and salinity measurements. Biological hauls with a plankton net were made over one period of 25 hours and several periods of about 8 hours from up to 6 holes at various locations. The biomass of each sample was measured. Biological samples and hydrological casts were also made from a ship from the ice channel adjacent to Arrival Heights. In the 1972-73 field season, a line of five hydrographic stations extending 16 miles west from Cape Armitage were used to make measurements of current observations at 100m intervals with observation periods separated by several days. This line of stations covered the major part of the cross section available for flux through the open ended Sound and it was hoped that new information on the circulation, particularly the tidal circulation in McMurdo would be reached. In the 1973-74 field season, a tide gauge was installed at the de-salinisation plant outfall at McMurdo and a current meter was installed through a hole in the ice about 2 miles west of Cape Armitage