The Arctic sea-ice is retreating faster than predicted by climate models and could become ice free during summer this century. The reduced sea-ice extent may effectively "unlock" the Arctic Ocean to increased human activities such as transit shipping and expanded oil and gas production. Travel time between Europe and the north Pacific Region can be reduced by up to 50 % with low sea-ice levels and the use of this route could increase substantially as the sea-ice retreats. Oil and gas activities already occur in the Arctic region and given the large undiscovered petroleum resources increased activity could be expected with reduced sea-ice. We use a bottom-up shipping model and a detailed global energy market model to construct emission inventories of Arctic shipping and petroleum activities in 2030 and 2050 given estimated sea-ice extents. The emission inventories are on a 1×1 degree grid and cover both short-lived components (SO₂, NO_x, CO, NMVOC, BC, OC) and the long-lived greenhouse gases (CO₂, CH₄, N₂O). We find rapid growth in transit shipping due to increased profitability with the shorter transit times compensating for increased costs in traversing areas of sea-ice. Oil and gas production remains relatively stable leading to reduced emissions from emission factor improvements. The location of oil and gas production moves into locations requiring more ship transport relative to pipeline transport, leading to rapid emissions growth from oil and gas transport via ship. Our emission inventories for the Arctic region will be used as input into chemical transport, radiative transfer, and climate models to quantify the role of Arctic activities in climate change compared to similar emissions occurring outside of the Arctic region

Wind field ensembles from six CMIP5 models force wave model time slices of the northeast Atlantic over the last three decades of the 20th and the 21st centuries. The future wave climate is investigated by considering the RCP4.5 and RCP8.5 emission scenarios. The CMIP5 model selection is based on their ability to reconstruct the present (1971–2000) extratropical cyclone activity, but increased spatial resolution has also been emphasized. In total, the study comprises 35 wave model integrations, each about 30 years long, in total more than 1000 years. Here annual statistics of significant wave height are analyzed, including mean parameters and upper percentiles. There is general agreement among all models considered that the mean significant wave height is expected to decrease by the end of the 21st century. This signal is statistically significant also for higher percentiles, but less evident for annual maxima. The RCP8.5 scenario yields the strongest reduction in wave height. The exception to this is the north western part of the Norwegian Sea and the Barents Sea, where receding ice cover gives longer fetch and higher waves. The upper percentiles are reduced less than the mean wave height, suggesting that the future wave climate has higher variance than the historical period.

Presently, the only offshore project for enhanced oil recovery using carbon dioxide, known as CO2-EOR, is in Brazil. Several desk studies have been undertaken, without any projects being implemented. The objective of this review is to investigate barriers to the implementation of large-scale offshore CO2-EOR projects, to identify recent technology developments, and to suggest non-technological incentives that may enable implementation. We examine differences between onshore and offshore CO2-EOR, emerging technologies that could enable projects, as well as approaches and regulatory requirements that may help overcome barriers. Our review shows that there are few, if any, technical barriers to offshore CO2-EOR. However, there are many other barriers to the implementation of offshore CO2-EOR, including: High investment and operation costs, uncertainties about reservoir performance, limited access of CO2 supply, lack of business models, and uncertainties about regulations. This review describes recent technology developments that may remove such barriers and concludes with recommendations for overcoming non-technical barriers. The review is based on a report by the Carbon Sequestration Leadership Forum (CSLF).

Laboratory experiments on the growth of sea ice in a very thin plastic tank filled with salt water, cooled from above and insulated with thermopane, clearly show the formation and development of brine drainage channels. The sea-water freezing cell is 0.3 cm thick by 35 cm wide by 50 cm deep; the thermopane insulation permits the ice interior to be photographed. Experimentally, we observe that vertical channels with diameters of 1 to 3 mm and associated smaller feeder channels extend throughout the ice sheet. Close examination of the brine channels show that their diameter at the ice-water interface is much narrower than higher up in the ice, so that the channel has a "neck" at the interface. Further, oscillations occur in the brine channels, in that brine flows out of the channel followed by a flow of sea-water up into the channel. Theoretically, a qualitative theory based on the difference in pressure head between the brine inside the ice and the sea-water provides a consistent explanation for the formation of the channels, and the onset of a convective instability explains the existence of the neck. Finally, an analysis based on the presence of the brine-channel neck provides an explanation for the observed oscillations. RESUME. La formation des reseaux de drainage, de la saumure dans la jeune glace de mer. Des experiences de laboratoires ont ete conduites sur la croissance de la glace d e mer dans un reservoir de plastique tres fin , rempli d'eau sa lee, refroidi par au-dessus et isole avec un panneau thermique. Elles ont clairement montre la formation et le developpement de canaux de drainage d e la saumure. La cellule de congelation de I'eau a 0,3 cm d'epaisseur, 35 cm de large et 50 cm de profondeur ; le panneau isolant permet de photographier la glace a l'interieur. Experimentalement, nous observon~ d es canaux verticaux avec des diametres de 1 a 3 mm associes a des canaux d'alimentation plus petits etendus a travel's la feuille de glace. Un examen attentif des canaux de saumure montre que leur diametre a l'interface eau-glace est beaucoup plus faible que plus haut dans la glace, de sorte que le canal presente un etranglement a I'interface. Plus tard, il se produit des oscillations dans les canaux de saumure par lesquels, a I'ecoulement de la saumure par le canal, succede un flot d'eau de mer montant dans le canal. Sur le plan theorique, une hypothese qualitative basee sur la difference de pression entre la saumure a I'interieur d e la glace et I'eau de mer, donne une explication satisfaisante pour la formation de canaux, e t I'apparition d'une instabilite d e convection explique I'existence de I'etranglement. Finalement, une analyse basee sur la presence de l'etranglement des canaux de saumure procure une explication des oscillations ob3crvees.ZUSAMMENFASSUNG. Die Bildu/lg van Systemell zur Salzsolc-Drainage infrischem Meereis. Laboruntersuchungen tiber das Wachstum von Meereis in einem sehr dilnnen, mit Salzwasser geftillten Plastikbehtilter, der von oben gekilhlt und mit Thermopane isoliert war, zeigen ...

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