The flow of warm salty water toward the Nordic Seas is of fundamental importance to the climate of central and northern Europe. In an effort to gain an improved quantitative assessment of these fluxes a program was started in 2008 to measure upper-ocean currents from the high-seas ferry Norröna, which operates out of the Faroes to Iceland and Denmark. The current measurements were made with an acoustic Doppler current profiler mounted in the Norröna's hull. Starting in fall of 2013 monthly deployments of Expendable BathyThermographs give comprehensive information on the temperature field. These velocity and temperature data can be combined to estimate mean volume and temperature fluxes (referenced to 0°C) for the two sections. Archived hydrographic data give us the corresponding salt transport. Thanks to an array of 12 tall moorings across the Blosseville Basin that measured currents, temperature, and salinity net transport of volume, temperature, and salt between Iceland and Greenland can also be estimated. By combining the velocity data from these three sections the strength of the Nordic Seas branch of the meridional overturning circulation is estimated to be 7.7 ± 0.8 Sv where 1 Sv = 10 6 m 3 /s. Imposing the constraint of zero net volume and salt flux, the corresponding heat and freshwater fluxes are estimated to be 264 ± 27 TW (1 TW = 10 12 W) and À0.104 ± 0.01 Sv, respectively. The uncertainties in heat and freshwater fluxes are largely governed by volume fluxes. The Norröna program is ongoing.Plain Language Summary The climate of central and northern Europe depends upon the flow of warm water into the northern North Atlantic and Nordic Seas. This study uses directly measured currents from the high-seas ferry Norröna in regular traffic between Denmark, the Faroes and Iceland to determine in great detail the flow of warm salty water into the Nordic Seas. An extensive array of current meters deployed between Iceland and Greenland covers all exchange with the Nordic Seas west of Iceland. During its transit through the Nordic Seas the warm and salty North Atlantic water loses its heat to the atmosphere, sinks, and eventually spills back across the sills between Greenland, Iceland, the Faroes, and Scotland into the deep North Atlantic. As these waters sink, they entrain cooled water from the Labrador and Irminger Seas. Without this overflow of dense water from the Nordic Seas the northern North Atlantic would become much cooler because of the cessation of warm water flow north to maintain the overturning process. Thus quantifying the flow of warm water into the Nordic Seas and tracking how it might change over time is one of the overarching questions regarding the climate of North Atlantic and surrounding landmasses.

Neutral endopeptidase-24.11 (neprilysin; NEP/CD10) is a cell surface metallopeptidase expressed by prostatic epithelial cells that degrades various bioactive peptides including endothelin. Endothelin-converting enzyme (ECE), the key enzyme of endothelin biosynthesis, catalyses the final processing step in the pathway. Neuropeptide substrates of NEP, including endothelin, have been implicated in the growth of androgen-independent prostate cancer. We have surveyed the expression of NEP and ECE in a range of prostate cancer cell lines. Western analysis reveals that ECE-1 is expressed abundantly in all the malignant cell lines tested, except for LNCaP. In contrast, LNCaP cells express high levels of NEP, while NEP was not detected in PC-3, DU145 and other metastatic cell lines that were tested. Of the normal immortalized prostate epithelial cell lines, PNT1a shows equivalent amounts of NEP and ECE. PNT2-C2 shows poor NEP expression but an abundance of ECE. P4E6, by comparison, has low levels of both ECE and NEP. These differences in expression may render these cell lines useful in experimental models for future study. Benign prostatic hyperplasia primary epithelial cells express much higher levels of NEP than malignant primary epithelial cells, but neither show ECE expression. On the other hand, surrounding stromal cell populations have detectable ECE levels. An absence of ECE in malignant and benign prostatic hyperplasia cells of primary epithelial origin suggests an important role for stromal interaction and paracrine production of ECE within the host. The upregulation of ECE expression in metastatic cells in culture may be indicative of its role in metastatic progression. A differential profile of ECE and NEP could contribute to an abundance of mitogenic peptides aiding the progression of androgen-independent prostate cancer.

Meltwater from Greenland is an important freshwater source for the North Atlantic Ocean, released into the ocean at the head of fjords in the form of runoff, submarine melt and icebergs. The meltwater release gives rise to complex in-fjord transformations that result in its dilution through mixing with other water masses. The transformed waters, which contain the meltwater, are exported from the fjords as a new water mass “Glacially Modified Water” (GMW). Here we use summer hydrographic data collected from 2013 to 2019 in Upernavik, a major glacial fjord in northwest Greenland, to describe the water masses that flow into the fjord from the shelf and the exported GMWs. Using an Optimum Multi-Parameter technique across multiple years we then show that GMW is composed of 57.8 ±8.1% Atlantic Water, 41.0 ±8.3% Polar Water, 1.0 ±0.1% subglacial discharge and 0.2 ±0.2% submarine meltwater. We show that the GMW fractional composition cannot be described by buoyant plume theory alone since it includes lateral mixing within the upper layers of the fjord not accounted for by buoyant plume dynamics. Consistent with its composition, we find that changes in GMW properties reflect changes in the AW and PW source waters. Using the obtained dilution ratios, this study suggests that the exchange across the fjord mouth during summer is on the order of 50 mSv (compared to a freshwater input of 0.5 mSv). This study provides a first order parameterization for the exchange at the mouth of glacial fjords for large-scale ocean models.

We analyze 11 years (2003–2013) of repeat temperature and salinity sections from across the New England shelf break south of Cape Cod during early summer (June–July). The mean sections resolved the shelf break front which supports the Shelf Break Jet, a vital component of the regional circulation. Individual sections showed a great deal of variability associated with meanders in the shelf break front consistent with previous studies in the region. Over the 11 year record, the shelf region (inshore of the 100 m isobath) warmed by 0.26 °C yr −1, with the majority of this warming occurring shallower than 20 m (0.58 °C yr −1). The full‐depth trend agrees well with previous studies of shelf warming to the north and the south of our study region. The temperature and salinity of the offshore edge of the Cold Pool Water on the shelf did not change significantly during this period. The surface warming on the shelf resulted in a decrease in near‐surface density of 0.12 kg m −3 yr −1 and an increase in stratification between 10 and 15 m of 6.7×10−5 s −2 yr −1. Offshore of the shelf break, the Slope Water also warmed and became more saline by 0.21 °C yr −1 and 0.04 yr −1 respectively, resulting in a maximal reduction in density of 0.01 kg m −3 yr −1. In the Shelf Break Front, there is some evidence of freshening and a reduction in density, which may have resulted from an offshore shift in the Cold Pool but the statistical significance is small.

The Denmark Strait Overflow (DSO) is an important source of dense water input to the deep limb of the Atlantic Meridional Overturning Circulation (AMOC). It is fed by separate currents from the north that advect dense water masses formed in the Nordic Seas and Arctic Ocean which then converge at Denmark Strait. Here we identify an annual salinity cycle of the DSO, characterized by freshening in winter and spring. The freshening is linked to freshening of the Shelfbreak East Greenland Current in the Blosseville Basin north of the Denmark Strait. We demonstrate that the East Greenland Current advects fresh pycnocline water above the recirculating Atlantic Water, which forms a low salinity lid for the overflow in Denmark Strait and in the Irminger Basin. This concept is supported by intensified freshening of the DSO in lighter density classes on the Greenland side of the overflow. The salinity of the DSO in the Irminger Basin is significantly correlated with northerly/northeasterly winds in the Blosseville Basin at a lag of 3–4 months, consistent with estimated transit times. This suggests that wind driven variability of DSO source water exerts an important influence on the salinity variability of the downstream DSO, and hence the composition of the deep limb of the AMOC.