HR: 16:00h
AN: OS22D-01    [PDF]
TI: Dcadal Variation of the Surface Water pCO2 in the Western and Central Equatorial Pacific Ocean
AU: * Takahashi, T
EM: taka@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 United States
AU: Sutherland, S C
EM: suth@ldeo.columbia.edu
AF: Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964 United States
AU: Feely, R A
EM: feely@pmel.noaa.gov
AF: Pacific Marine Environmental Laboratory, NOAA, 7600 Sand Point Way, NE,, Seattle, WA 98115 United States
AU: Cosca, C E
EM: cosca@pmel.noaa.gov
AF: Pacific Marine Environmental Laboratory, NOAA, 7600 Sand Point Way, NE,, Seattle, WA 98115 United States
AB: The equatorial Pacific Ocean is known to undergo significant changes on interannual (e. g. El Nino/La Nina ) and decadal time scales. This area is a major source of CO2 to the atmosphere during non-El Nino periods, but near neutral during strong El Nino periods. Over decadal time scales, the North Pacific Ocean has undergone major physical and biological changes commonly called the Pacific Decadal Oscillation (PDO). Most recent and well-documented major shifts occurred in 1977 and 1989. While causes and effects of PDO have been investigated extensively in recent years, its effects on CO2 chemistry have not yet been identified. The partial pressure of CO2 (pCO2) measured in surface waters over the past two decades are used to examine the effect of the 1989 Pacific Decadal Oscillation (PDO) phase shift on the CO2 chemistry of the equatorial Pacific waters. During 1980-1989, the surface water pCO2 (corrected for temperature changes and atmospheric CO2 uptake) in the central and western equatorial Pacific decreased at a mean rate of about -20 matm per decade, whereas it increased at about +20 matm per decade during 1990-2001. These changes alter the CO2 sink/source flux of the equatorial Pacific significantly in a decadal time scale: in the central equatorial Pacific, the net sea-to-air CO2 flux would be affected by as much as 30 to 40 percent in a decadal time scale, while the western warm pool area would change from a CO2 sink to source.
DE: 0312 Air/sea constituent fluxes (3339, 4504)
DE: 0322 Constituent sources and sinks
DE: 0330 Geochemical cycles
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting