Record Details

Seasonal spreading of the Persian Gulf water mass in the Arabian Sea

DRS at CSIR-National Institute of Oceanography

View Archive Info
 
 
Field Value
 
Title Seasonal spreading of the Persian Gulf water mass in the Arabian Sea
 
Creator Prasad, T.G.
Ikeda, M.
PrasannaKumar, S.
 
Subject water masses
thermocline
heat transfer
temperature profiles
salinity profiles
seasonal variations
 
Description The characteristics of the subsurface salinity maximum associated with the Persian Gulf Water mass (PGW) are used to quantify the spreading and mixing of PGW in the thermocline of the Arabian Sea based on a bimonthly climatology of temperature and salinity. Examination of the seasonal cycles of heat and freshwater fluxes in the Persian Gulf region indicates that PGW forms as a result of elevated evaporative cooling in conjunction with reduced isolation during winter. Maps are presented of the distributions of depth, salinity, and geostrophic flow on sigma sub(theta) = 26.5, which nearly coincides with the core of the PGW. After intense mixing in the Strait of Hormuz, the property fields suggest that warm (> 17 degrees C) and high-salinity (> 36.2 psu) PGW enters the Arabian Sea to form a subsurface salinity extremum between 200 and 300 m. Variability in the distribution of PGW in the Arabian Sea associated with monsoonal changes in the Arabian Sea circulation have been found. During the winter monsoon, there is southward spreading of PGW along the western boundary; during summer it is not present. Lateral mixing with low-salinity water from the Bay of Bengal in the region south of 10 degrees N and along the west coast of India during winter accounts for changes in the characteristics of PGW along these paths. Associated with the Findlater Jet during summer, the entire thermohaline structure is vertically displaced along the coasts of Somalia and Arabia. Ekman convergence in the central Arabian Sea accounts for deepening of the PGW. Either lateral or vertical mixing would cause changes in PGW properties in these regions. During this time, PGW spreads predominantly southward along the central Arabian Sea, as indicated by a tongue of high salinity
 
Date 2009-01-07T11:01:35Z
2009-01-07T11:01:35Z
2001
 
Type Journal Article
 
Identifier Journal of Geophysical Research (C: Oceans), Vol.106; 17059-17071p.
http://drs.nio.org/drs/handle/2264/1599
 
Language en
 
Rights Copyright [2001]. All efforts have been made to respect the copyright to the best of our knowledge. Inadvertent omissions, if brought to our notice, stand for correction and withdrawal of document from this repository.
 
Publisher American Geophysical Union