Organochlorine Pesticides and PAHs in the Surface Water and Atmosphere of the North Atlantic and Arctic Ocean

2009 ◽  
Vol 43 (15) ◽  
pp. 5633-5639 ◽  
Author(s):  
Rainer Lohmann ◽  
Rosalinda Gioia ◽  
Kevin C. Jones ◽  
Luca Nizzetto ◽  
Christian Temme ◽  
...  
2009 ◽  
Vol 6 (1) ◽  
pp. 971-994 ◽  
Author(s):  
E. H. Shadwick ◽  
T. Papakyriakou ◽  
A. E. F. Prowe ◽  
D. Leong ◽  
S. A. Moore ◽  
...  

Abstract. The Arctic Ocean is expected to be disproportionately sensitive to climatic changes, and is thought to be an area where such changes might be detected. The Arctic hydrological cycle is influenced by: runoff and precipitation, sea ice formation/melting, and the inflow of saline waters from Bering and Fram Straits and the Barents Sea Shelf. Pacific water is recognizable as intermediate salinity water, with high concentrations of dissolved inorganic carbon (DIC), flowing from the Arctic Ocean to the North Atlantic via the Canadian Arctic Archipelago. We present DIC data from an east-west section through the Archipelago, as part of the Canadian International Polar Year initiatives. The fractions of Pacific and Arctic Ocean waters leaving the Archipelago and entering Baffin Bay, and subsequently the North Atlantic, are computed. The eastward transport of carbon from the Pacific, via the Arctic, to the North Atlantic is estimated. Altered mixing ratios of Pacific and freshwater in the Arctic Ocean have been recorded in recent decades. Any climatically driven alterations in the composition of waters leaving the Arctic Archipelago may have implications for anthropogenic CO2 uptake, and hence ocean acidification, in the subpolar and temperate North Atlantic.


2020 ◽  
Vol 17 (9) ◽  
pp. 2553-2577
Author(s):  
Coraline Leseurre ◽  
Claire Lo Monaco ◽  
Gilles Reverdin ◽  
Nicolas Metzl ◽  
Jonathan Fin ◽  
...  

Abstract. The North Atlantic is one of the major ocean sinks for natural and anthropogenic atmospheric CO2. Given the variability of the circulation, convective processes or warming–cooling recognized in the high latitudes in this region, a better understanding of the CO2 sink temporal variability and associated acidification needs a close inspection of seasonal, interannual to multidecadal observations. In this study, we investigate the evolution of CO2 uptake and ocean acidification in the North Atlantic Subpolar Gyre (50–64∘ N) using repeated observations collected over the last 3 decades in the framework of the long-term monitoring program SURATLANT (SURveillance de l'ATLANTique). Over the full period (1993–2017) pH decreases (−0.0017 yr−1) and fugacity of CO2 (fCO2) increases (+1.70 µatm yr−1). The trend of fCO2 in surface water is slightly less than the atmospheric rate (+1.96 µatm yr−1). This is mainly due to dissolved inorganic carbon (DIC) increase associated with the anthropogenic signal. However, over shorter periods (4–10 years) and depending on the season, we detect significant variability investigated in more detail in this study. Data obtained between 1993 and 1997 suggest a rapid increase in fCO2 in summer (up to +14 µatm yr−1) that was driven by a significant warming and an increase in DIC for a short period. Similar fCO2 trends are observed between 2001 and 2007 during both summer and winter, but, without significant warming detected, these trends are mainly explained by an increase in DIC and a decrease in alkalinity. This also leads to a pH decrease but with contrasting trends depending on the region and season (between −0.006 and −0.013 yr−1). Conversely, data obtained during the last decade (2008–2017) in summer show a cooling of surface waters and an increase in alkalinity, leading to a strong decrease in surface fCO2 (between −4.4 and −2.3 µatm yr−1; i.e., the ocean CO2 sink increases). Surprisingly, during summer, pH increases up to +0.0052 yr−1 in the southern subpolar gyre. Overall, our results show that, in addition to the accumulation of anthropogenic CO2, the temporal changes in the uptake of CO2 and ocean acidification in the North Atlantic Subpolar Gyre present significant multiannual variability, not clearly directly associated with the North Atlantic Oscillation (NAO). With such variability it is uncertain to predict the near-future evolution of air–sea CO2 fluxes and pH in this region. Thus, it is highly recommended to maintain long-term observations to monitor these properties in the next decade.


1998 ◽  
Vol 49 (2) ◽  
pp. 171-182 ◽  
Author(s):  
Klas S. Lackschewitz ◽  
Karl-Heinz Baumann ◽  
Bettina Gehrke ◽  
Hans-Joachim Wallrabe-Adams ◽  
Jörn Thiede ◽  
...  

Marine records from the Reykjanes Ridge indicate ice sheet variations and abrupt climate changes. One of these records, ice-rafted detritus (IRD), serves as a proxy for iceberg discharges that probably indicates ice sheet fluctuations. The IRD records suggest that iceberg discharge 68,000–10,000 yr B.P. happened more frequently than the 7000- to 10,000-yr spacing of the Heinrich events. An IRD peak 67,000 to 63,000 yr B.P. further suggests that the Middle Weichselian glaciation started about 12,000 yr earlier in the North Atlantic than in the Norwegian Sea. Several later IRD events, in contrast, correlate with Norwegian Sea IRD-rich layers and imply coeval ice sheet advances in the North Atlantic and the Norwegian Sea. Coccoliths in a core from the Reykjanes Ridge show distinct peaks in species that record occasional inflow of warm surface water during the last glaciation, as previously reported from the eastern Labrador Sea. High abundances of coccoliths, together with a decrease of Neogloboquadrina pachyderma sin. and relatively low δ18O values, imply enhanced advection of the North Atlantic Current 69,000–67,000 yr B.P., 56,000–54,000 yr B.P., 35,000–33,000 yr B.P., and 26,000–23,000 yr B.P. This advection provided a regional moisture source for extension of ice sheets onto the shelf. In contrast, most of the IRD events are characterized by cold polar surface water masses indicating rapid variations in ocean surface conditions.


Author(s):  
D. W. Minter

Abstract A description is provided for Pleistophora hippoglossoideos, which infects Hippoglossoides platessoides, American plaice (family Pleuronectidae) and Solea solea, the Dover sole (family Soleidae), in the North Atlantic, Baltic Sea and Arctic Ocean. Some information on its morphology, dispersal and transmission and conservation status is given, along with details of its geographical distribution (Europe (Baltic Sea, Norway, UK) and North America (Canada, Nova Scotia)) and hosts (Hippoglossoides platessoides, H. limandoides and Solea solea).


2021 ◽  
Author(s):  
Yarisbel Garcia Quintana ◽  
Paul G. Myers ◽  
Kent Moore

<p>Nares Strait, between Greenland and Ellesmere Island, is one of the main pathways connecting the Arctic Ocean to the North Atlantic. The multi-year sea ice that is transported through the strait plays an important role in the mass balance of Arctic sea-ice as well as influencing the climate of the North Atlantic region. This transport is modulated by the formation of ice arches that form at the southern and northern of the strait.  The arches also play an important role in the maintenance of the North Water Polynya (NOW) that forms at the southern end of the strait. The NOW is one of the largest and most productive of Arctic polynyas. Given its significance, we use an eddy-permitting regional configuration of the Nucleus for European Modelling of the Ocean (NEMO) to explore sea-ice variability along Nares Strait, from 2002 to 2019. The model is coupled with the Louvain-la-Neuve (LIM2) sea ice thermodynamic and dynamic numerical model and is forced by the Canadian Meteorological Centre’s Global Deterministic Prediction System Reforecasts.</p><p>We use the model to explore the variability in ocean and sea ice characteristics along Nares Strait. The positive and negative degree days, measures of ice decay and growth, along the strait are consistent with the warming that the region is experiencing. Sea-ice production/decay did not show any significant change other than an enhanced decay during the summers of 2017-1019. Sea-ice thickness on the other hand has decreased significantly since 2007. This decrease has been more pronounced along the northern (north of Kane Basin) portion of the strait. What is more, ocean model data indicates that since 2007 the northern Nares Strait upper 100m layer has become fresher, indicating an increase in the freshwater export out of the Arctic Ocean and through the strait. The southern portion of the strait, on the other hand, has become warmer and saltier, which would be consistent with an influx of Irminger Water as proposed by previous modelling results. These changes could impact the formation and stability of the ice arch and hence the cessation of ice transport down Nares Strait as well as contributing to changes in the characteristics of the NOW. </p>


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