Deep-SeaResearch. Vol. 37. No. 7, pp. 116q--I 175. 191~. 01916-0149,q) ~.{.~ 4-0.l]O Pnnted in Great Britain. Pergamon Press pie Interannual variability in the upper ocean in the North Atlantic, summer 1983 and 1986 H. LEACH* (Received 25 Augltst 1989; in revised f.orm 29 March 1990; accepted 9 April 1990) Abstract--The influence of the seasonal mean wind on the thermohaline structure of the upper ocean in the North Atlantic is considered using two examples from the section Azores-Greenland. INTRODUCTION INTERANNUAL variations in the properties of the upper ocean may be both a consequence and a cause of anomalous atmospheric conditions. A number of authors have reported interannual variations in the properties of the upper ocean in the North Atlantic. COLEaROOa and TAYLOR (1979), for example, found a correlation between stronger westerlies and lower sea-surface temperatures in the mid-latitude North Atlantic. In this paper data from the section Azores-Greenland at the same season of two different years are compared and contrasted, and possible causes of the difference discussed. EXPERIMENT In the years 1983 and 1986 measurcments were made along a section from the Azores in the direction of Greenland using the Kiel Sea-Rover System, essentially a towed, undulating vehicle fitted with a CTD. This delivered temperature and conductivity measurements over the top 70 m of the ocean, enabling calculation of the salinity there too. In both the years the measurements were made at the same time of year, namely late June-early July. The Sea-Rover System is documented in BAUER et al. (1985), the 1983 expedition in LEACll et al. (1987), BAUER(1988) and BAUER et al. (in preparation). The 1986 expedition is documented in STRASS (1989), STIO.SS and WOODS (1988) and a comprehensive representation of the results of all the Sea-Rover expeditions is being prepared (LEACH et al., in preparation). RESULTS Figure 1 shows the temperature and salinity in the mixed layer and at 60 m depth from the section from 1983. The temperature (Fig. la) shows a fairly uniform decrease from south to north with a sudden drop marking the Polar Front at about 52.5°N. In salinity • Institut fucr Mcereskundc, Ducsternbrooker Wcg 20, D23(}0 Kid l, F.R.G. "Prcsent address: Dcpartmcnt of Earth Sciences, University of Liverpool, P.O. Box 147, Liverpool L69 3BX, U.K. 1169