HR: 14:25h
AN: OS43C-04    [Abstracts]
TI: Variations of Temperature-Salinity Relationship in the Pycnocline of the Eastern Equatorial Pacific Ocean Associated With El Ni\~{n}o
AU: * Wang, O
EM: owang@pacific.jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, MS 300-323, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Fukumori, I
EM: if@pacific.jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, MS 300-323, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Lee, T
EM: tlee@pacific.jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, MS 300-323, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AU: Johnson, G C
EM: gregory.c.johnson@noaa.gov
AF: NOAA/Pacific Marine Environmental Laboratory, Bldg. 3, 7600 Sand Point Way NE, Seattle, WA 98115 United States
AU: Cheng, B
EM: bcheng@jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, MS 300-323, 4800 Oak Grove Drive, Pasadena, CA 91109 United States
AB: Temperature-Salinity (T-S) relationship variability in the pycnocline of the eastern equatorial Pacific Ocean (NINO3 region, $5\deg$S-$5\deg$N, $150\deg$W-$90\deg$W) over the last two decades is investigated using observational data and model simulation. A numerical model simulation using the MITgcm (Massachusetts Institute of Technology General Circulation Model) suggests that, during El Ni\~{n}o years, the water in the eastern equatorial Pacific Ocean becomes saltier (by 0.1 to 0.2) and warmer (by 0.5 to $1\deg$C) on density surfaces within the pycnocline. This simulation is consistent with Conductivity-Temperature-Depth (CTD) data collected mostly during Tropical Atmosphere Ocean (TAO) mooring maintenance cruises. The cause of observed variations in T-S relationship between El Ni\~{n}o and non-El Ni\~{n}o years is numerically investigated. The origin of the subject water mass is identified using the adjoint of a simulated passive tracer. The higher salinity during El Ni\~{n}o is attributed to larger convergence of saltier water from the Southern Hemisphere and smaller convergence of fresher water from the Northern Hemisphere.
DE: 4215 Climate and interannual variability (3309)
DE: 4231 Equatorial oceanography
DE: 4255 Numerical modeling
DE: 4283 Water masses
DE: 4522 El Ni¤o
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting