This study was motivated by a strong warming signal seen in mooring‐based and oceanographic survey data collected in 2004 in the Eurasian Basin of the Arctic Ocean. The source of this and earlier Arctic Ocean changes lies in interactions between polar and sub‐polar basins. Evidence suggests such changes are abrupt, or pulse‐like, taking the form of propagating anomalies that can be traced to higher‐latitudes. For example, an anomaly found in 2004 in the eastern Eurasian Basin took ∼1.5 years to propagate from the Norwegian Sea to the Fram Strait region, and additional ∼4.5–5 years to reach the Laptev Sea slope. While the causes of the observed changes will require further investigation, our conclusions are consistent with prevailing ideas suggesting the Arctic Ocean is in transition towards a new, warmer state.

Over a decade of mooring measurements in the western Fram Strait at 78°50′N shows that the annual mean liquid freshwater flux (FWF) in the East Greenland Current is relatively constant at −1274 ± 453 km3 yr−1 (−40.4 ± 14.4 mSv) despite the fact that the annual mean total volume transport of the EGC has more than doubled since 2001. This is shown to be due to an increase of the transport in the deeper ocean and the fact that the largest FW content is present on the East Greenland shelf and not in the core of the EGC. In order to capture the FWF on the shelf modeling results of NAOSIM are included showing that a mean contribution of FWF on the shelf of at least −807 ± 357 km3 yr−1 (−25.6 ± 11.3 mSv) should be added to the FWF obtained for the EGC. When compared to the extra input of freshwater required to account for the 1960–1990 freshening of the northern North Atlantic, the observed variations in the 1998–2008 EGC liquid freshwater fluxes are small.

Abstract. The meridional oceanic transports of dissolved inorganic carbon and oxygen were calculated using six transoceanic sections occupied in the South Atlantic between 11 øS and 30øS. The total dissolved inorganic carbon (TCO2) data were interpolated onto conductivity-temperature-depth data to obtain a high-resolution data set, and Ekman, depth-dependent and depth-independent components of the transport were estimated. Uncertainties in the depth-independent velocity distribution were reduced using an inverse model. The inorganic carbon transport between 11 øS and 30øS was southward,

Two major water masses dominate the deep layers in the Mariana and Caroline Basins: the Lower Circumpolar Water (LCPW), arriving from the Southern Ocean along the slopes north of the Marshall Islands, and the North Pacific Deep Water (NPDW) reaching the region from the northeastern Pacific Ocean. Hydrographic and moored observations and multibeam echosounding were performed in the East Mariana and the East Caroline Basins to detail watermass distributions and flow paths in the area. The LCPW enters the East Mariana Basin from the east. At about 13ЊN, however, in the southern part of the basin, a part of this water mass arrives in a southward western boundary flow along the Izu-Ogasawara-Mariana Ridge. Both hydrographic observations and moored current measurements lead to the conclusion that this water not only continues westward to the West Mariana Basin as suggested before, but also provides bottom water to the East Caroline Basin. The critical throughflow regions were identified by multibeam echosounding at the Yap Mariana Junction between the East and West Mariana Basins and at the Caroline Ridge between the East Mariana and East Caroline Basins. The throughflow is steady between the East and West Mariana Basins, whereas more variability is found at the Caroline Ridge. At both locations, throughflow fluctuations are correlated with watermass property variations suggesting layerthickness changes. The total transport to the two neighboring basins is only about 1 Sverdrup (1Sv ϵ 10 6 m 3 s Ϫ1 ) but has considerable impact on the watermass structure in these basins. Estimates are given for the diapycnal mixing that is required to balance the inflow into the East Caroline Basin. Farther above in the water column, the high-silica tongue of NPDW extends from the east to the far southwestern corner of the East Mariana Basin, with transports being mostly southward across the basin.

No abstract