Transfer function vs. modern analog technique for estimating Pliocene sea-surface temperatures based on planktic foraminiferal data, western Equatorial Pacific Ocean

The secondary entry portal of the Indonesian Throughflow (ITF) from the Pacific to Indian Oceans is considered to be via the Halmahera Sea (HS). However, few ITF studies have been done within the passage. This motivated the Internal Tides and Mixing in the Indonesian Througflow (INDOMIX) program to conduct direct measurements of currents and its variability across the eastern path of the ITF. This study focused on the intra-seasonal variability of near-bottom current in HS (129°E, 0°S), its origin and correlation with surface zonal winds and sea surface height over the equatorial Pacific Ocean. The result showed a strong northwestward mean flow with velocity exceeding 40 cm/s, which represented the current-following topography with the northwest orientation. Meridional current component was much stronger than the zonal component. The energy of power spectral density (PSD) of the current peaked on 14-days and 27-days periods. The first period was presumably related to the tidal oscillation, but the latter may be associated with surface winds perturbation. Furthermore, cross-PSD revealed a significant coherency between the observed currents and the surface zonal winds in the central equatorial Pacific zonal winds (180°E-160°W), which corroborates westward propagation of intra-seasonal sea surface height signals along the 5°S with its mean phase speeds of 50 cm/s, depicting the low-latitude westward Rossby waves on intra-seasonal band. Keywords: current, equatorial Pacific Ocean, zonal winds, sea surface height, Halmahera Sea

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Estimation method for vertical distribution of phytoplankton using monitoring data at the western equatorial Pacific Ocean

OCEANS 2006 - Asia Pacific ◽

10.1109/oceansap.2006.4393921 ◽

2006 ◽

Author(s):

N. Nakatani ◽

M. Yabu ◽

T. Okuno

Keyword(s):

Pacific Ocean ◽

Vertical Distribution ◽

Estimation Method ◽

Equatorial Pacific ◽

Monitoring Data ◽

Equatorial Pacific Ocean ◽

Western Equatorial Pacific

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Distribution of 226Ra and 210Pb in the mixed layer of the western equatorial Pacific Ocean

Marine and Freshwater Research ◽

10.1071/mf96095 ◽

1997 ◽

Vol 48 (5) ◽

pp. 371 ◽

Cited By ~ 2

Author(s):

Philip H. Towler ◽

J. David Smith

Keyword(s):

Surface Water ◽

Pacific Ocean ◽

Residence Time ◽

Mixed Layer ◽

Equatorial Pacific ◽

Nutrient Concentrations ◽

Residence Times ◽

Equatorial Pacific Ocean ◽

Depth Profiles ◽

Western Equatorial Pacific

The residence time of particulate and dissolved 210Pb in the upper layer of the western equatorial Pacific Ocean is examined. Activities of dissolved 226Ra, dissolved and particulate 210Pb, and particulate 210Po were determined to a depth of 300 m in a series of depth profiles collected along a transect across the equator at 155˚E in November 1993. Total 210Pb in the surface water decreased from 2·7 Bq m-3 at 10˚N to 1·8 Bq m-3 at 10˚S. Dissolved 210Pb generally decreased with depth but showed subsurface (100–150 m) maxima at 10˚N and 5˚N. The nutrient concentrations at 300 m were highest at these stations, suggesting some degree of upwelling. Calculations indicate that the residence times of dissolved (<0·45 µm) and particulate (>0·45 µm) 210Pb in the top 300 m were 4·6–9·6 years and 0·15–0·29 year respectively.

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