General distribution of water masses within the eastern Caribbean Sea during the winter of 1972 and fall of 1973

Abstract

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.

On the world ocean circulation. Volume I, Some global features/North Atlantic circulation

“…These deep and bottom layers also have low 02 and high silicate (Figures 1-40c and 1-40d). The hydrography of this layer (and others as well) in the Caribbean has been described by Morrison and Nowlin (1982). According to SR91 (see also Atkinson, 1983;Iselin, 1936;and Richardson, 1977) Worthington (1959) superimposed.…”

Neogene Changes in Caribbean Paleoproductivity and the Diversity and Paleobiogeography of Deep-sea Benthic Foraminifera

“…The change in bottom-water is attributed to the foundering of the Northern Nicaragua Rise which led to the development of the North Component Deep Water in the Caribbean (Droxler et al, 1998). Presently, North Atlantic Deep water has been found to enter the Colombian Basin between Jamaica and Hispaniola (Morrison and Nowlin, 1982;Haddad and Droxler, 1996) Bolivina seminuda Barmawidjaja et al, 1992 Lagena spp. Corliss and Chen, 1988 Bolivina spp.…”

“…The change to North Atlantic Deep Water in the Caribbean is seen in these changes (Morrison and Nowlin, 1982;Keller and Barron, 1983;Duque-Caro, 1990;Haddad and Droxler, 1996 (Barron and Keller, 1982). Modern deep circulation is thought to have been established during this interval, and faunal changes and the resultant impact on diversity can partially be attributed to increased corrosivity due to the influx of Antarctic…”

“…The change in bottom-water is attributed to the foundering of the Northern Nicaragua Rise which led to the development of the North Component Deep Water in the Caribbean (Droxler et al, 1998). Presently, North Atlantic Deep water has been found to enter the Colombian Basin between Jamaica and Hispaniola (Morrison and Nowlin, 1982;Haddad and Droxler, 1996). Duque-Caro (1990) examined Neogene paleobiogeography and paleoceanography in regards to the evolution of the Central American Seaway (CAS) in the area of northwest South America and found that beginning at ~16 Ma, changes occurred in bottom water circulation, associated with the gradual closure of the CAS.…”

“…The first, and oldest event is the differentiation of bottom water source between the Caribbean and equatorial Eastern Pacific (EEP), with North Atlantic Deep Water occupying the Caribbean noted at ~16 Ma (Morrison and Nowlin, 1982;Keller and Barron, 1983;Duque-Caro, 1990;and Haddad and Droxler, 1996). The second noted event is the deep circulation barrier between the two regions at ~12 Ma (Duque-Caro, 1990), followed by the third event, seaway constriction, at ~8 Ma (Wright et al, 1991, Billups, 2002.…”