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We present a global ocean climatology of dissolved inorganic carbon δ13C (‰) corrected for the 13C‐Suess effect, preindustrial δ13C. This was constructed by first using Olsen and Ninnemann's (2010) back‐calculation method on data from 25 World Ocean Circulation Experiment cruises to reconstruct the preindustrial δ13C on sections spanning all major oceans. Next, we developed five multilinear regression equations, one for each major ocean basin, which were applied on the World Ocean Atlas data to construct the climatology. This reveals the natural δ13C distribution in the global ocean. Compared to the modern distribution, the preindustrial δ13C spans a larger range of values. The maxima, of up to 1.8‰, occurs in the subtropical gyres of all basins, in the upper and intermediate waters of the North Atlantic, as well as in mode waters with a Southern Ocean origin. Particularly strong gradients occur at intermediate depths, revealing a strong potential for using δ13C as a tracer for changes in water mass geometry at these levels. Further, we identify a much tighter relationship between δ13C and apparent oxygen utilization (AOU) than between δ13C and phosphate. This arises because, in contrast to phosphate, AOU and δ13C are both partly reset when waters are ventilated in the Southern Ocean and underscore that δ13C is a highly robust proxy for past changes in ocean oxygen content and ocean ventilation. Our global preindustrial δ13C climatology is openly accessible and can be used, for example, for improved model evaluation and interpretation of sediment δ13C records. A global ocean climatology of the preindustrial C‐13 distribution, corrected for anthropogenic influencesPreindustrial C‐13 spans a larger range of values compared to the modern distribution, with particularly strong intermediate ocean gradientsC‐13 is found to be a highly robust proxy for past changes in oxygen content and ocean ventilation

The fCO2in the Greenland and Norwegian Seas surface water varied significantly during the period from 1995 to 1997. Comparison of fCO2data from winter 1995 with data from winter 1997 showed that sea surface fCO2decreased between these winters by 20–30 μatm in the central Greenland Sea, and the potential CO2uptake during the winters of 1995 and 1997 was 3.9·10-3Gt C month-1and 5.9·10-3Gt C month-1(based on Wanninkhof’s relationship for the gas transfer coeYcient), respectively. This difference in CO2fluxes can be attributed to lower sea surface temperatures and more extensive sea ice cover in 1997, and these observations were related to increased convection in the Greenland Sea during winter 1997. Larger amplitudes in the seasonal variations of CO2flux were also seen during the other seasons in the period 1996–97, compared to 1995. Over the years of investigation in the Greenland Sea, the carbon flux showed an increasing trend of 9·10-4Gt C yr-1into the ocean, which may be related to the anthropogenic input of carbon to the atmosphere. The Greenland and Norwegian Seas appear to be sinks for atmospheric CO2and together absorb approximately 0.12 ± 0.015 Gt C yr-1.

Annual measurements of the frontal variations of Briksdalsbreen are compared with twentieth-century records of summer temperature, winter precipitation and mass budget to evaluate the effects of climatic change on the glacier fluctuations. Frontal variations are shown to be determined by both summer temperature and winter precipitation. Between AD 1901 and 1931 the glacier front was in a more-or-less stable position. Warm summers in the 1930s and 1940s caused a significant retreat of the glacier, reaching a maximum rate of annual retreat of 84 m in 1948. Cooler summers in the late 1940s led to a stabilization of the glacier front from 1952. Between 1987/88 and 1993/94 the terminus advanced 231 m, 155 m of which has occurred after 1992. The increased glacier net mass balance in western Norway after the 1988/89 season resulted in the largest annual glacier advances measured this century at Briksdalsbreen (75 and 80 m in 1992/93 and 1993/94, respectively). Present knowledge about glacier history in western Norway since the termination of the last glaciation about 9000 years ago suggests that annual glacier expansions of such magnitude only occurred during the 'Little Ice Age' (c. AD 1650-1920). The lag time of frontal response of Briksdalsbreen to a change in annual net balance has been calculated to be 3-4 years, which confirms that glacier termini can react rapidly to short-term climatic changes.

A compilation of Holocene glacial advances throughout the world is compared with summer solar insolation integrated over the Northern Hemisphere and the magnitudes of global acid fallout from volcanic eruptions north of 20°S*** estimated from the acidity signal of annual ice layers in the Crëte and Camp Century ice cores in Greenland. Correlation analysis between glacial advances versus volcanic eruptions yielded a correlation coefficient of r = 0.71. A ‘climatic forcing’ curve (solar insolation and volcanic eruptions weighted 1:1) versus glacial advances increased the correlation coefficient to r = 0.90. This suggests that the combined effect of volcanic aerosols and orbital-related Northern Hemisphere summer insolation may have been the primary forcing mechanism of worldwide climate and glacier fluctuations throughout the Holocene.

The rapidly rising levels of atmospheric and oceanic CO2 from the burning of fossil fuels has lead to well-established international concerns over dangerous anthropogenic interference with climate. Disposal of captured fossil fuel CO2 either underground, or in the deep ocean, has been suggested as one means of ameliorating this problem. While the basic thermodynamic properties of both CO2 and seawater are well known, the problem of interaction of the two fluids in motion to create a plume of high C02/low pH seawater has been modeled, but not tested. We describe here a novel experiment designed to initiate study of this problem. We constructed a small flume, which was deployed on the sea floor at 4 km depth by a remotely operated vehicle, and filled with liquid CO2. Seawater flow was forced across the surface by means of a controllable thruster. Obtaining quantitative data on the plume created proved to be challenging. We observed and sensed the interface and boundary layers, the formation of a solid hydrate, and the low pH/high CO2 plume created, with both pH and conductivity sensors placed downstream. Local disequilibrium in the CO2 system components was observed due to the finite hydration reaction rate, so that the pH sensors closest to the source only detected a fraction of the CO2 emitted. The free CO2 molecules were detected through the decrease in conductivity observed, arid the disequilibrium was confirmed through trapping a sample in a flow cell and observing an unusually rapid drop in pH to an equilibrium value. [ABSTRACT FROM AUTHOR]