A Lagrangian study of surfacepCO2dynamics in the eastern equatorial Pacific Ocean

摘要: [1] We characterized pCO2 variability on hourly to weekly timescales during the 14-day GasEx-2001 Lagrangian drifter experiment in eastern equatorial Pacific Ocean. Underway was recorded at 5 m depth as ship closely followed a drogued drifter. Dissolved O2 (DO) measured 10 and 15 depths using situ sensors deployed drogue. Diel DO is evaluated simple model that accounts for air-sea exchange, vertical mixing, heating, net community metabolism. Mixed-layer local (vertical) entrainment are estimated with Price Weller Pinkel (PWP) mixed-layer model. The mean observed 472.0 ± 1.8 μatm diel increase of 2–6 most days, near coincident time peak temperature. biogeochemical reveals heating primary source variability, but production depletion CO2 shallow warm layer due gas exchange reduced heating-driven by ∼1–4 1–2 each day, respectively. same parameterizations also accurately predict amplitude. In model, atmospheric depletes total surface layer, depleted water mixed isolated underlying nocturnal convection. 10- 15-m series corroborate these predicted dynamics. Over study, offset expected ∼14 decrease production, resulting nearly constant pCO2. Consequently, acts sustain high fluxes upwelled advects westward South Equatorial Current.