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The Arctic Ocean (AO) is an important basin for global oceanic carbon dioxide (CO2) uptake, but the mechanisms controlling air—sea gas fluxes are not fully understood, especially over short and long timescales. The oceanic sink of CO2 is an important part of the global carbon budget. Previous studies have shown that in the AO differences in the partial pressure of CO2 (DpCO2) and gas transfer velocity (k) both contribute significantly to interannual air—sea CO2 flux variability, but that k is unimportant for multidecadal variability. This study combined Earth Observation (EO) data collected in 2010 with the in situ pCO2 dataset from Takahashi et al. (2009) (T09) using a recently developed software toolbox called FluxEngine to determine the importance of k and DpCO2 on CO2 budgets in two regions of the AO — the Greenland Sea (GS) and the Barents Sea (BS) with their continental margins. Results from the study indicate that the variability in wind speed and, hence, the gas transfer velocity, generally play a major role in determining the temporal variability of CO2 uptake, while variability in monthly DpCO2 plays a major role spatially, with some exceptions.
The debate on the climatic impact of Arctic change is currently focused on the fate of the perennial sea-ice and the climatic and social effects of its disappearance. Developments in our observing techniques mean that we are in prospect of being technically able to describe the ocean-atmosphere-cryosphere system of high northern latitudes operating as a complete system for the first time. Understanding this system and improving its predictability in models seems to be our most direct way of extending the ability of society to mitigate for or adapt to its changes, including global change. The integrated Arctic Ocean Observing System (iAOOS), described here, is a means of piecing together the available PIs, gear, ships and funding on the pan-Arctic scale that seems necessary to making the attempt, and the International Polar Year (2007–2009) provides the necessary stimulus for doing so.
According to the results of recent research, besides the atmospheric circulation, it is heat transport to the Arctic Ocean (AO) by ocean currents, the West Spitsbergen Current (WSC) in particular, that is playing a significant role in the process of Arctic warming. Data collected by the Institute of Oceanology, Polish Academy of Sciences (IO PAS), in the Norwegian and Greenland Seas, and Fram Strait during the last 20 years reveal considerable changes in the amount of heat transported by the WSC into the Arctic Ocean. An increase in Atlantic Water (AW) temperature and the intensification of heat transport were observed in 2004–06; after this period, both parameters decreased. The aim of this study was to find out whether the fluctuations in heat input by the WSC have influenced the sea-ice distribution around Svalbard. In fact they do, but oceanic heat transport should nonetheless be regarded as just one of many processes influencing sea-ice behaviour.
Global climate changes which has been observed over the recent years affects organisms occurring in the Arctic seas and the functioning of the whole maritime ecosystems there. The research note presents and briefly analyses the biological diversity of the Arctic Ocean and the most important factors which change the relations between organisms and the environment in the Arctic.
The water masses in Fram Strait have been analyzed on the basis of hydrographic casts taken in summer 1984 during the MIZEX 84 experiment. In particular, θ − S diagrams for 16 areas, each 5◦ in longitude and 1◦ in latitude, covering the strait from 77◦N to 81◦ N are used to characterize the water masses and discuss their possible origin. Near the surface, the East Greenland Polar Front clearly separates the lighter, cold and fresh Polar Water (PW) from the heavier, warm and saline Atlantic Water (AW). In the upper ocean, the data show a large spreading of the temperature maximum in the θ − S space associated with different modes of the AW recirculating southward below the PW. Two geographically distinct salinity minima are found in the intermediate layer below the AW. The denser one, in the Boreas Basin, is a feature typical of the Arctic Intermediate Water (AIW) formed by winter convection to the south of the strait, while the lighter one is sandwiched in the Arctic Ocean outflow between the AW layer and the Upper Polar Deep Water (UPDW) characterized by a downward salinity increase. In the deep layer, two salinity maxima are present. The shallower (and warmer) one, associated with the Canadian Basin Deep Water (CBDW), appears all along the East Greenland Slope. A similar but weaker maximum is also found in the southeastern part of the strait. This maximum is perhaps a remnant of the maximum in the East Greenland Current after it has been recirculated back to the strait around the cyclonic gyres of the Nordic Seas. The deeper one appears typically as a near-bottom salinity jump characteristic of the Eurasian Basin Deep Water (EBDW). The jump is found in two distinct areas of the strait, to the north-west in the Lena Trough and to the south-east in the rift valley of the Knipovich Ridge. The maximum in the former area should have been advected from the Arctic Ocean below the CBDW, while the maximum in the latter area might have originated from haline convection on the adjacent shelves. Some EBDW is trapped in the Molloy Deep over a denser water with salinity decreasing down to the bottom and temperature in the range of the Greenland Sea Deep Water (GSDW).
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