The continuity of water masses along the western boundary of the Tasman and Coral Seas

1968 ◽  
Vol 19 (2) ◽  
pp. 77 ◽  
Author(s):  
DJ Rochford
Keyword(s):  
Water Mass ◽  
New Caledonia ◽  
Core Layer ◽  
Water Masses ◽  
Western Boundary ◽  
Intermediate Water ◽  
North West ◽  
The North ◽  
Coral Sea ◽  
Intermediate Water Mass

Hydrological data of the Umitaka Maru (December 1967) and of H.M.A.S. Gascoyne (November-December 1965) have been used to show continuity of selected water masses from the north-west Coral Sea to the continental margin off New South Wales. The core layer properties of these water masses (salinity, temperature, oxygen) indicate that these water masses of the north-west Coral Sea are formed by the inflow from the east of the South Equatorial water mass (0 m), the upper salinity maximum water mass (150-200 m) of the central South Pacific, and of the Antarctic Intermediate water mass (800-1000 m). The inflow of the first two occurs immediately south of the Solomon Is. whilst that of the third occurs between New Caledonia and the New Hebrides. Continuity of the upper oxygen maximum of the 200-800 m layer was not examined because of doubts as to its existence as a separate water mass.

Hydrology of the Indian Ocean. III. Water masses of the upper 500 metres of the South-east Indian Ocean

1964 ◽  
Vol 15 (1) ◽  
pp. 25 ◽  
Author(s):  
DJ Rochford
Keyword(s):  
Indian Ocean ◽  
Persian Gulf ◽  
Water Mass ◽  
Sea Water ◽  
Core Layer ◽  
Water Masses ◽  
Intermediate Water ◽  
Surface Currents ◽  
North West ◽  
East Indian

The following seven water masses have been identified, and their distribution traced during several seasons of the year: Red Sea mass, with the same distribution and properties in 1962 as the north-west Indian Intermediate described in 1959-60; Persian Gulf mass, which is confined to the region south of Indonesia and is limited in extent of easterly flow by the opposing flow of Banda Intermediate water; upper salinity minimum mass, entering via Lombok Strait and moving zonally in the direction of the prevailing surface currents, a secondary movement of this water mass towards north-west Australia is limited by the northern boundary of a south-east Indian high salinity water mass. This latter water mass occurs as three separate core layers north of 22-23� S. The deep core layer mixes with waters of the oxygen maximum below it, the mid-depth core layer mixes with Persian Gulf and upper salinity minimum water masses, and the upper core layer mixes with the Arabian Sea water mass. The latter water mass spreads eastwards to about 120� E. and southwards to north-west Australia, in conformity with surface currents. A sixth water mass enters with the counter-current and is found as a salinity maximum within the thermocline to about 20� S. A seventh water mass characterized by a salinity maximum around temperatures of 28-29�C has a limited distribution and an unknown origin. Both of these water masses move in the direction of surface currents.

scholarly journals Water mass distributions and transports for the 2014 GEOVIDE cruise in the North Atlantic

2018 ◽  
Vol 15 (7) ◽  
pp. 2075-2090 ◽  
Author(s):  
Maribel I. García-Ibáñez ◽  
Fiz F. Pérez ◽  
Pascale Lherminier ◽  
Patricia Zunino ◽  
Herlé Mercier ◽  
...  
Keyword(s):  
North Atlantic ◽  
Water Mass ◽  
Water Levels ◽  
Water Masses ◽  
Meridional Overturning Circulation ◽  
Labrador Sea ◽  
Intermediate Water ◽  
North East ◽  
The North ◽  
The North Atlantic

Abstract. We present the distribution of water masses along the GEOTRACES-GA01 section during the GEOVIDE cruise, which crossed the subpolar North Atlantic Ocean and the Labrador Sea in the summer of 2014. The water mass structure resulting from an extended optimum multiparameter (eOMP) analysis provides the framework for interpreting the observed distributions of trace elements and their isotopes. Central Waters and Subpolar Mode Waters (SPMW) dominated the upper part of the GEOTRACES-GA01 section. At intermediate depths, the dominant water mass was Labrador Sea Water, while the deep parts of the section were filled by Iceland–Scotland Overflow Water (ISOW) and North-East Atlantic Deep Water. We also evaluate the water mass volume transports across the 2014 OVIDE line (Portugal to Greenland section) by combining the water mass fractions resulting from the eOMP analysis with the absolute geostrophic velocity field estimated through a box inverse model. This allowed us to assess the relative contribution of each water mass to the transport across the section. Finally, we discuss the changes in the distribution and transport of water masses between the 2014 OVIDE line and the 2002–2010 mean state. At the upper and intermediate water levels, colder end-members of the water masses replaced the warmer ones in 2014 with respect to 2002–2010, in agreement with the long-term cooling of the North Atlantic Subpolar Gyre that started in the mid-2000s. Below 2000 dbar, ISOW increased its contribution in 2014 with respect to 2002–2010, with the increase being consistent with other estimates of ISOW transports along 58–59° N. We also observed an increase in SPMW in the East Greenland Irminger Current in 2014 with respect to 2002–2010, which supports the recent deep convection events in the Irminger Sea. From the assessment of the relative water mass contribution to the Atlantic Meridional Overturning Circulation (AMOC) across the OVIDE line, we conclude that the larger AMOC intensity in 2014 compared to the 2002–2010 mean was related to both the increase in the northward transport of Central Waters in the AMOC upper limb and to the increase in the southward flow of Irminger Basin SPMW and ISOW in the AMOC lower limb.

scholarly journals Water masses in the Atlantic Ocean: characteristics and distributions

Ocean Science ◽  
2021 ◽  
Vol 17 (2) ◽  
pp. 463-486
Author(s):  
Mian Liu ◽  
Toste Tanhua
Keyword(s):  
Atlantic Ocean ◽  
Deep Water ◽  
Bottom Water ◽  
Water Mass ◽  
Sea Water ◽  
Weddell Sea ◽  
Water Masses ◽  
Global Ocean ◽  
Intermediate Water ◽  
The North

Abstract. A large number of water masses are presented in the Atlantic Ocean, and knowledge of their distributions and properties is important for understanding and monitoring of a range of oceanographic phenomena. The characteristics and distributions of water masses in biogeochemical space are useful for, in particular, chemical and biological oceanography to understand the origin and mixing history of water samples. Here, we define the characteristics of the major water masses in the Atlantic Ocean as source water types (SWTs) from their formation areas, and map out their distributions. The SWTs are described by six properties taken from the biased-adjusted Global Ocean Data Analysis Project version 2 (GLODAPv2) data product, including both conservative (conservative temperature and absolute salinity) and non-conservative (oxygen, silicate, phosphate and nitrate) properties. The distributions of these water masses are investigated with the use of the optimum multi-parameter (OMP) method and mapped out. The Atlantic Ocean is divided into four vertical layers by distinct neutral densities and four zonal layers to guide the identification and characterization. The water masses in the upper layer originate from wintertime subduction and are defined as central waters. Below the upper layer, the intermediate layer consists of three main water masses: Antarctic Intermediate Water (AAIW), Subarctic Intermediate Water (SAIW) and Mediterranean Water (MW). The North Atlantic Deep Water (NADW, divided into its upper and lower components) is the dominating water mass in the deep and overflow layer. The origin of both the upper and lower NADW is the Labrador Sea Water (LSW), the Iceland–Scotland Overflow Water (ISOW) and the Denmark Strait Overflow Water (DSOW). The Antarctic Bottom Water (AABW) is the only natural water mass in the bottom layer, and this water mass is redefined as Northeast Atlantic Bottom Water (NEABW) in the north of the Equator due to the change of key properties, especially silicate. Similar with NADW, two additional water masses, Circumpolar Deep Water (CDW) and Weddell Sea Bottom Water (WSBW), are defined in the Weddell Sea region in order to understand the origin of AABW.

Late Quaternary paleoceanography of deep and intermediate water masses off Gaspé Peninsula, Gulf of St. Lawrence: foraminiferal evidence

1993 ◽  
Vol 30 (7) ◽  
pp. 1390-1403 ◽  
Author(s):  
Cyril G. Rodrigues ◽  
James A. Ceman ◽  
Gustavs Vilks
Keyword(s):  
Deep Water ◽  
Water Mass ◽  
Late Quaternary ◽  
Water Masses ◽  
Intermediate Water ◽  
Low Salinity ◽  
New Information ◽  
Intermediate Water Mass ◽  
Gaspe Peninsula ◽  
Gaspé Peninsula

Radiocarbon-dated benthonic foraminiferal zones in three cores provide new information on the evolution of the deep and intermediate water masses off Gaspé Peninsula. The deglacial phase in the deep Laurentian Channel began before 14 000 BP and was characterized by low-salinity (<20‰) or alternating low-salinity and saline (~35‰) water. This was followed by a cold saline phase, which ended ca. 13 500 BP, and a salinity minimum (30–33.5‰), which began ca. 12 100 BP. Between 8700 and 7900 BP, the temperature and salinity of the deep water mass increased, resulting in the modern deep water mass (temperature 4–6 °C, salinity 34.5–34.9‰) at the end of the Goldthwait Sea episode. The salinity of the deep water was apparently controlled by the meltwater flux from the ice front during the deglacial phase. After the deglacial phase the characteristics of the deep water mass were determined by the composition of offshore water entering the Laurentian Channel. Runoff from the Lake Agassiz – Great Lakes system does not appear to have mixed with the deep water of the Goldthwait Sea. The deglacial phase in Chaleur Trough, which is within the intermediate water mass, began before 12 200 BP. The temperature of the intermediate water mass has remained close to 0 °C after deglaciation; however, the salinity has increased from 25–30‰ at 12 200 BP to about 33.5‰ by 5900 BP.

Some hydrological features of the eastern Arafura Sea and the Gulf of Carpentaria in August 1964

1966 ◽  
Vol 17 (1) ◽  
pp. 31 ◽  
Author(s):  
DJ Rochford
Keyword(s):  
Organic Phosphorus ◽  
High Surface ◽  
Coastal Region ◽  
Biological Action ◽  
Water Masses ◽  
North West ◽  
The North ◽  
Coral Sea ◽  
Arafura Sea ◽  
Phosphate Nitrate

Charts of the distribution of salinity, temperature, inorganic phosphate, nitrate nitrogen, oxygen, and particulate organic phosphorus, for the eastern Arafura Sea and Gulf of Carpentaria in August 1964 are presented. Interrelationships of these properties show that at least three water masses were identifiable in this month. Two were very low in nutrients (phosphate less than 0.20, nitrate less than 1.0 �g-atom/l) but differed in salinity (less than 33.00‰ and greater than 35.50‰). The third was high in nutrients (phosphate greater than 1.40, nitrate greater than 17 �g-atom/l) and had salinities between 33.80 and 34.70‰. The high nutrient water mass was derived from Banda Sea slope water at around 100-150 m, wlth its nutrients increased subsequently by biological action. The other two water masses were formed in the coastal region of West Irian and the Coral Sea. High surface oxygen saturation (139%) and accumulation of organic phosphorus in near-bottom waters of the eastern Arafura Sea were the result of an uplift of Banda slope waters, much earlier in the year than August. In the Gulf of Carpentaria, the August salinity temperature characteristics were formed by the southward drift along the eastern margin of Coral Sea waters, which increased in salinity and decreased in temperature by evaporation. Low salinity water of the previous summer occurred in August, only in the north-west of the gulf.

Coral Sea flow budgets in winter

1973 ◽  
Vol 24 (3) ◽  
pp. 203 ◽  
Author(s):  
PD Scully-Power
Keyword(s):  
New Caledonia ◽  
Solomon Islands ◽  
Volume Transport ◽  
Source Water ◽  
Equatorial Undercurrent ◽  
North West ◽  
Geostrophic Balance ◽  
The North ◽  
Coral Sea ◽  
Anticyclonic Eddies

Winter cruises in the Coral Sea indicate very little southerly volume transport a across 20�S. Most of the inflow from the east between New Caledonia and the Solomon Islands leaves the area between these islands and New Guinea. This outflow is considered to form a major source water for the lower cell of the Equatorial Undercurrent (Cromwell Current) which is in geostrophic balance. South of 20°S., the East Australian Current is postulated to be a series of southward meandering anticyclonic eddies near the edge of the continental shelf. In the north-west Coral Sea there is high variability of volume transport both in strength and direction, and no regular pattern can be discerned.

scholarly journals Seasonal variability of intermediate water masses in the Gulf of Cadiz: implications of the Antarctic and Subarctic seesaw model

2019 ◽  
Author(s):  
David Roque ◽  
Ivan Parras-Berrocal ◽  
Miguel Bruno ◽  
Ricardo Sánchez-Leal ◽  
Francisco Javier Hernández-Molina
Keyword(s):  
Seasonal Variability ◽  
Water Mass ◽  
Water Masses ◽  
Meridional Overturning Circulation ◽  
Intermediate Water ◽  
Gulf Of Cadiz ◽  
Local Circulation ◽  
Gulf Of Cádiz ◽  
Intermediate Water Mass ◽  
The Antarctic

Abstract. Global circulation of intermediate water masses has been extensively studied; however, its regional and local circulation along continental margins and variability and implications on sea floor morphologies are still not well known. In this study the intermediate water mass variability in the Gulf of Cádiz and adjacent areas has been analysed and its implications discussed. Remarkable seasonal variations of the Antarctic Intermediate Water (AAIW) and the Subarctic Intermediate Water (SAIW) are determined. During autumn a greater presence of the AAIW seems to be related to a reduction in the presence of SAIW and Eastern North Atlantic Central Water (ENACW). This interaction also affects the Mediterranean Outflow Water (MOW), which is pushed by the AAIW toward the upper continental slope. In the rest of the seasons, the SAIW is the predominant water mass reducing the presence of the AAIW. This seasonal variability for the predominance of these intermediate water masses is explained by a novel model based on the concatenation of several wind-driven processes acting during the different seasons. Our finding is important for a better understanding of regional intermediate water mass variability with implications in the Atlantic Meridional Overturning Circulation (AMOC) but further research is needed in order to decode their changes during the geological past and their role, especially related to the AAIW, in controlling both the morphology and the sedimentation along the continental slopes.

scholarly journals WATER MASS ANALYSIS OF THE INDONESIAN THROUGHFLOW BY MEANS OF PRINCIPLE COMPONENT ANALYSIS

2010 ◽  
Vol 4 (1) ◽  
Author(s):  
Yuli Naulita
Keyword(s):  
Principle Component Analysis ◽  
Water Mass ◽  
Principal Component ◽  
Core Layer ◽  
Component Analysis ◽  
Statistical Technique ◽  
Water Masses ◽  
Indonesian Throughflow ◽  
Principle Component ◽  
The North

The water masses in both routes of Indonesia Throughflow (ITF) from historical hydrographic data are examined by means of the Principal Component Analysis (PCA), a multivariate statistical technique, during the southeast monsoon and northwest monsoon, and compared with the TS diagrams. The temperature and dissolves oxygen always play in the same PC, which describeds a variability contribution of the water mass characters, while salinity in a different PC. The relationship of the water masses parameters may indicate the character of dissolved oxygen as a non-conservation tracer. The Principle Component Analysis may also be used to follow the trendds of core layer attenuation as verified by the salinity corresponds at the PC. It will be higher with S-max and S-min and more closely resemble the sources. This condition is shown in the waters close to the main sources in the Pacific, like Sulawesi, Malkuku and Halmahera Sea, where both the salinity extrema can still be observed. Conversely, in the Banda and Timor Sea, where S-max and S-min are greatly attenuated even completely remove, the correspondence of salinity in the water mass character variability becomes smaller. As seen on TS and TO diagrams, PCA graphics are also showed the dominant of the north Pacific water in the western route seas, the Sulawesi, Makasar Strait and the Florest Sea, but relatively salty water of South Pacific origin is observed in the Halmahera Sea, particularly in the northwest monsoon. The strong seasonal variablity of surface water in the Indonesian can also be observed in the PCA graphics. Keywords: Water Mass, Indonesian Throughflow, PCA.

scholarly journals Seasonal variability of intermediate water masses in the Gulf of Cádiz: implications of the Antarctic and subarctic seesaw

Ocean Science ◽  
2019 ◽  
Vol 15 (5) ◽  
pp. 1381-1397 ◽  
Author(s):  
David Roque ◽  
Ivan Parras-Berrocal ◽  
Miguel Bruno ◽  
Ricardo Sánchez-Leal ◽  
Francisco Javier Hernández-Molina
Keyword(s):  
Seasonal Variability ◽  
Water Mass ◽  
Water Masses ◽  
Meridional Overturning Circulation ◽  
Intermediate Water ◽  
Gulf Of Cadiz ◽  
Local Circulation ◽  
Gulf Of Cádiz ◽  
Intermediate Water Mass ◽  
The Antarctic

Abstract. Global circulation of intermediate water masses has been extensively studied; however, its regional and local circulation along continental margins and variability and implications on sea floor morphologies are still not well known. In this study the intermediate water mass variability in the Gulf of Cádiz (GoC) and adjacent areas has been analysed and its implications discussed. Remarkable seasonal variations of the Antarctic Intermediate Water (AAIW) and the Subarctic Intermediate Water (SAIW) are determined. During autumn a greater presence of the AAIW seems to be related to a reduction in the presence of SAIW and Eastern North Atlantic Central Water (ENACW). This interaction also affects the Mediterranean Water (MW), which is pushed by the AAIW toward the upper continental slope. In the rest of the seasons, the SAIW is the predominant water mass reducing the presence of the AAIW. This seasonal variability for the predominance of these intermediate water masses is explained in terms of the concatenation of several wind-driven processes acting during the different seasons. Our finding is important for a better understanding of regional intermediate water mass variability with implications in the Atlantic Meridional Overturning Circulation (AMOC), but further research is needed in order to decode their changes during the geological past and their role, especially related to the AAIW, in controlling both the morphology and the sedimentation along the continental slopes.

scholarly journals Distribution of Water Masses in the Atlantic Ocean based on GLODAPv2

2019 ◽  
Author(s):  
Mian Liu ◽  
Toste Tanhua
Keyword(s):  
Atlantic Ocean ◽  
Bottom Water ◽  
Water Mass ◽  
Potential Temperature ◽  
Weddell Sea ◽  
Water Masses ◽  
General Distribution ◽  
Intermediate Water ◽  
The North ◽  
The Antarctic

Abstract. The distribution of the main water masses in the Atlantic Ocean are investigated with the Optimal Multi-Parameter (OMP) method. The properties of the main water masses in the Atlantic Ocean are described in a companion article; here these definitions are used to map out the general distribution of those water masses. Six key properties, including conservative (potential temperature and salinity) and non-conservative (oxygen, silicate, phosphate and nitrate), are incorporated into the OMP analysis to determine the contribution of the water masses in the Atlantic Ocean based on the GLODAP v2 observational data. To facilitate the analysis the Atlantic Ocean is divided into four vertical layers based on potential density. Due to the high seasonal variability in the mixed layer, this layer is excluded from the analysis. Central waters are the main water masses in the upper/central layer, generally featuring high potential temperature and salinity and low nutrient concentrations and are easily distinguished from the intermediate water masses. In the intermediate layer, the Antarctic Intermediate Water (AAIW) from the south can be detected to ~30 °N, whereas the Subarctic Intermediate Water (SAIW), having similarly low salinity to the AAIW flows from the north. Mediterranean Overflow Water (MOW) flows from the Strait of Gibraltar as a high salinity water. NADW dominates the deep and overflow layer both in the North and South Atlantic. In the bottom layer, AABW is the only natural water mass with high silicate signature spreading from the Antarctic to the North Atlantic. Due to the change of water mass properties, in this work we renamed to North East Antarctic Bottom Water NEABW north of the equator. Similarly, the distributions of Labrador Sea Water (LSW), Iceland Scotland Overflow Water (ISOW), and Denmark Strait Overflow Water (DSOW) forms upper and lower portion of NADW, respectively roughly south of the Grand Banks between ~50 and 66 °N. In the far south the distributions of Circumpolar Deep Water (CDW) and Weddell Sea Bottom Water (WSBW) are of significance to understand the formation of the AABW.

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