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Quasi‐synoptic descriptions of the circulation and water mass distributions within the eastern Caribbean Sea are presented for winter 1972 and fall of 1973. Vertical sections of properties within these basins and along the axes of the major passages into this region, together with property distributions on isopycnal surfaces (chosen to be representative of the principal water masses), are used to describe the circulation. The flow paths of the various water masses into and out of the region are identified. The water masses identified within the eastern Caribbean Sea and their points of entrance into the region are as follows: Subtropical Underwater enters through the northern Lesser Antilles, 18°C Sargasso Sea Water enters through the passages of the Greater Antilles, Tropical Atlantic Central Water and Antarctic Intermediate Water enter through the southern Lesser Antilles, and North Atlantic Deep Water enters the Venezuelan Basin through Anegada‐Jungfern Passage and enters the Colombian Basin between Jamaica and Hispaniola. Water mass distributions and dynamic maps are used to compare and contrast the quasi‐synoptic current patterns present within the eastern Caribbean Sea during the winter of 1972 and fall of 1973. During both periods, a two‐stream westward current was observed in the Grenada Trough and Venezuelan Basin. Within the Colombian Basin, these streams combine to form one northwestward flow out of the region. The area where these streams combine is controlled by the intensity of a dynamic high located south of Hispaniola. The intensity of this high appears to be controlled by the curl of the local wind stress and tends to weaken during the fall when the wind stress curl reaches a minimum. Therefore ‘seasonal’ changes in the current pattern may actually be associated with seasonal changes in the atmospheric forcing. Geostrophic computations give a net westward transport for the Caribbean Current system of 29×106 m3 s−1 during both seasons. This net westward transport agrees quite well with transport estimates of flow into and out of this region by previous investigators.

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The United States Southern Ocean Joint Global Ocean Flux Study (JGOFS), also known as AESOPS (Antarctic Environment and Southern Ocean Process Study), focused on two distinct regions. The "rst was the Ross-Sea continental shelf, where a series of six cruises collected a variety of data from October 1996 through February 1998. The second area was the southwest Paci"c sector of the Southern Ocean, spanning the Antarctic Circumpolar Current (ACC) at &1703W. Data were collected within this region during "ve cruises from September 1996 through March 1998, as well as during selected transits between New Zealand and the Ross Sea. The "rst results of these cruses are described in this issue. The Ross-Sea investigation extensively sampled the area along 76330 S to elucidate the temporal patterns and processes that contribute to making this one of the Antarctic's most productive seas. Hydrographic distributions con"rm that strati"cation is initiated early in October within the polynya, generating an environment that is favorable for phytoplankton growth. Signi"cant spatial variations in mixed-layer depths, the timing of the onset of strati"cation, and the strength of the strati"cation existed throughout the growing season. Nutrient concentrations re#ected phytoplankton uptake, and reached their seasonal minimal in early February. Chlorophyll concentrations were maximal in early January, whereas productivity was maximal in late November, which re#ects the temporal uncoupling between growth and biomass accumulation in the region. Independent estimates of biogenic export suggest that majority of the #ux occurred in late summer and was strongly uncoupled from phytoplankton growth. The ACC region exhibited seasonal changes that in some cases were greater than those observed in the Ross Sea.0967-0645/00/$ -see front matter 2000 Published by Elsevier Science Ltd. PII: S 0 9 6 7 -0 6 4 5 ( 0 0 ) 0 0 0 5 9 -X Sea ice covered much of the region south of the Polar Front in winter, and retreated rapidly in late spring and early summer. Mixed layers throughout the region shoaled in summer due to surface heating, while the addition of freshwater from melting sea ice enhanced strati"cation in the Seasonal Ice Zone, creating conditions favorable for phytoplankton growth. For example, silicic acid concentrations decreased from initial values as high as 65 to less than 2 M within approximately 100 km (from 65.7 to 64.83S). Fluorescence values, however, showed less than a two-fold variation over the same distance. The vertical #ux of carbon in the Polar Front area is substantial, and marked variations in the composition of exported material exited over the region. The results provide a means whereby the controls of phytoplankton growth and organic matter #ux and remineralization can be analyzed in great detail. Additional results of the AESOPS project are discussed.