OCEANS OF N.Z. REGION

Press, Volume XC, Issue 27396, 8 July 1954, Page 8

OCEANS OF N.Z. REGION

INCREASED STUDY PLANNED

TEMPERATURE AND CURRENTS “The Press” Special Service „ WELLINGTON, July 7. Oceanography, the Cinderella s of New Zealand sciences, is to have its horizons widened. Within the next few years a scientific team will investigate the oceans of the New Zealand region in the fields of biology, physics, and marine geology. Preliminary work has been done in the three fields. Already completed and now being published are the fouryear investigations of surface temperature distribution in the SouthWest Pacific.

These investigations have helped to define the main ocean currents affecting New Zealand, the principal two being the warm current down the East Australian Coast which crosses the South Tasman and apparently strikes New Zealand somewhere about Milford Sound and the other warm current from the north which laps the East Coast of New Zealand. Both are branches of the South Equatorial Current.

The team will study the behaviour of these currents from season to season and from year to year. What happens to the current which crosses the South Tasman is not definitely known, and this will be one of the questions for which an answer is to be sought. The methods used will be the measurement of temperatures, and of salinity of the water at the surface and at depth.

The first year’s returns are already in from the special drift cards dropped by ships travelling from New Zealand and around the New Zealand coast. Their analysis will give further details of surface water movements which will prove valuable.

An ocean current can be recognised by measurement of the bodv of water or by the different properties of that water from that alongside it. The salinity and temperature will determine the presence of different types of plankton, the minute floating organisms on which fish feed and which some agriculturists say man will have one day to feed on to meet the exigencies of a growing world population. An accurate knowledge of surface currents is a. valuable aid to navigation.

While the general pattern of New Zealand’s weather is produced west of New Zealand, the temperature of the sea may affect certain local areas. The temperature of the surface of the sea is closely related to that of the bottom layer of air, which in turn has a local effect bn the weather.

An understanding of the seas around New Zealand forms the essential background for future investigations of fisheries’ problems and for many local oceanographic problems, such as silting of harbours and the water movements in such difficult navigational areas as Cook Strait. For example, it is at present thought that the warm north-flowing current may help to shift sediment up the West Coast of the South Island with adverse effects on harbour bars.