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Using an ocean carbon cycle model embedded in an ocean general circulation model, we examine how the budget of anthropogenic CO2 (Cant) is controlled by ocean dynamics. To complement recent studies showing only vertically integrated budgets, we provide a step-by-step description by making use of three different coarse grainings of the full vertical resolution of the ocean model in our budget analysis. For the 11 subdomains of the global ocean, these coarse grainings are (1) a one-layer (vertically integrated) budget, (2) a three-layer budget, and (3) an 11-layer budget. We largely focus on the Pacific circulation. We identify and quantify substantial carbon transport associated with the subtropical cells (STCs), which are dominant contributors to the meridional overturning circulation in the upper ocean in the tropics and subtropics, as playing a fundamental role in governing the ocean interior distribution of Cant. The upper branch of the STCs transports Cant-rich water from the tropics to the subtropics, contributing to the precondition for the high Cant inventory in mode waters. The lower branch of the STCs carries about two thirds of the transported Cant back to the tropics, while it largely excludes Subtropical Mode Waters. This work implies that the reemergence of Cant through recirculation within the STCs may lead to a reduced capacity for further Cant uptake via gas exchange into the surface ocean, potentially contributing to a positive carbon-climate feedback. [ABSTRACT FROM AUTHOR]

Air-sea CO2 fluxes over the Pacific Ocean are known to be characterized by coherent large-scale structures that reflect not only ocean subduction and upwelling patterns, but also the combined effects of wind-driven gas exchange and biology. On the largest scales, a large net CO2 influx into the extra-tropics is associated with a robust seasonal cycle, and a large net CO2 efflux from the tropics is associated with substantial inter-annual variability. In this work, we have synthesized estimates of the net air-sea CO2 flux from a variety of products drawing upon a variety of approaches in three sub-basins of the Pacific Ocean, i.e., the North Pacific extra-tropics (18° N-66° N), the tropical Pacific (18° S-18° N), and the South Pacific extra-tropics (44.5° S-18° S). These approaches include those based on the measurements of CO2 partial pressure in surface seawater (pCO2sw), inversions of ocean interior CO2 data, forward ocean biogeochemistry models embedded in the ocean general circulation models (OBGCMs), a model with assimilation of pCO2sw data, and inversions of atmospheric CO2 measurements. Long-term means, inter-annual variations and mean seasonal variations of the regionally-integrated fluxes were compared in each of the sub-basins over the last two decades, spanning the period from 1990 through 2009. A simple average of the long-term mean fluxes obtained with surface water pCO2 diagnostics and those obtained with ocean interior CO2 inversions are -0.47 ± 0.13PgCyr-1 in the North Pacific extra-tropics, +0.44 ± 0 .14PgCyr-1 in the tropical Pacific, and -0.37 ± 0.08PgCyr-1 in the South Pacific extra-tropics, where positive fluxes are into the atmosphere. This suggests that approximately half of the CO2 taken up over the North and South Pacific extra-tropics is released back to the atmosphere from the tropical Pacific. These estimates of the regional fluxes are also supported by the estimates from OBGCMs after adding the riverine CO2 flux, i.e., -0.49 ± 0.02PgCyr-1 in the North Pacific extratropics, +0.41 ± 0.05PgCyr-1 in the tropical Pacific, and -0.39 ± 0.11 PgCyr-1 in the South Pacific extra-tropics. The estimates from the atmospheric CO2 inversions show large variations amongst different inversion systems, but their median fluxes are consistent with the estimates from climatological pCO2sw data and pCO2sw diagnostics. In the South Pacific extra-tropics, where CO2 variations in the surface and ocean interior are severely under-sampled, the difference in the air-sea CO2 flux estimates between the diagnostic models and ocean interior CO2 inversions is larger (0.18 PgCyr-1). The range of estimates from forward OBGCMs is also large (-0.19 to -0.72 PgCyr-1). Regarding inter-annual variability of air-sea CO2 fluxes, positive and negative anomalies are evident in the tropical Pacific during the cold and warm events of the El Nino Southern Oscillation in the estimates from pCO2sw diagnostic models and from OBGCMs. They are consistent in phase with the Southern Oscillation Index, but the peak-to-peak amplitudes tend to be higher in OBGCMs (0.40 ± 0.09 PgCyr-1) than in the diagnostic models (0.27 ± 0.07PgCyr-1). [ABSTRACT FROM AUTHOR]

The article focuses on the quality control of the Southern Ocean data from the Pacific sector which are included in Carbon In the Atlantic (CARINA). It notes the use of crossover analysis between stations and inversion analysis of all crossover data to check the quality control of the Pacific sector. It infers that the outcome of the effort is an internally consistent, high-quality carbon data set for all cruises including the reference cruises.

Presents a summary of studies on carbon measurements made by the World Ocean Circulation Experiment/Joint Global Ocean Flux Study/Ocean Atmosphere Carbon Exchange Study in the Pacific Ocean. Analytical and statistical methods; Results of statistical analysis; Recommended adjustments in the development of unified data sets on Pacific carbon measurements.

Seasonal drawdown of dissolved inorganic carbon (DIC) in the subtropical upper ocean makes a significant contribution to net community production (NCP) globally. Although NCP requires macronutrient supply, surface macronutrients are chronically depleted, and their supply has been unable to balance the NCP demand. Here, we report nanomolar increases in surface nitrate plus nitrite (N+N, ~20 nM) and phosphate (PO 4 , ~15 nM) from summer to winter in the western subtropical North Pacific. Molar ratios of upward fluxes of DIC:N+N:PO 4 to the euphotic zone (< 100 m) were in near-stoichiometric balance with microbial C:N:P ratios (107~243:16~35:1). Comparison of these upward influxes with other atmospheric and marine sources demonstrated that total supply is largely driven by the other sources for C and N (93~96%), but not for P (10%), suggesting that nanomolar upward supply of P and its preferential recycling play a vital role in sustaining the NCP.

Background: On March 11, 2011, the Tohoku-Pacific Ocean earthquake (magnitude 9.0) struck the eastern part of Japan. Despite being far from the epicenter of the catastrophic earthquake, the effects were strongly felt in Tokyo, and the aftershocks continued for several months. There are no reports regarding the influence of earthquakes on migraine medication. The aim of our study was to determine the impact of earthquakes on prophylactic therapy with lomerizine in patients with migraine in Tokyo., Methods: The study included patients with migraine who were admitted to outpatient clinics in Tokyo between January 2010 and July 2010 or between January 2011 and July 2011 and who were prescribed lomerizine prophylactically for headache by specialists. We investigated clinical factors from the medical records for 26 of these patients., Results: The study population included 10 patients in 2010 and 16 patients in 2011. The frequency of headaches was reduced to under 5 days/month during February in both the groups. Compared to 2010, the frequency of headaches significantly increased in 2011 in March, April and May., Conclusion: Patients with migraine were sensitive to exposure to the earthquake and their headaches worsened despite successful prophylactic treatment with lomerizine before the Tohoku-Pacific Ocean earthquake., (© 2014 S. Karger AG, Basel.)

Shewanella violacea DSS12 is facultative piezophile isolated from the deep-sea. The expression of cydDC genes (required for d-type cytochrome maturation) of the organism is regulated by hydrostatic pressure. In this study, we analyzed the nucleotide sequence upstream of cydDC in detail and found that there are putative binding sites for the NarL protein which is part of a two-component regulatory system also containing the sensor protein NarX. Furthermore, we identified the narQP genes (homologues of narXL) from S. violacea DSS12 and demonstrated the heterologous expression of narP in Escherichia coli. These results will be helpful in examining pressure regulation of gene expression in S. violacea at the molecular level.