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A major puzzle of paleoclimatology is why, after a tong interval of cooling climate, each late Quaternary ice age ended with a relatively short warming leg called a termination. We here offer a comprehensive hypothesis of how Earth emerged from the last global ice age. A prerequisite was the growth of very large Northern Hemisphere ice sheets, whose subsequent collapse created stadial conditions that disrupted global patterns of ocean and atmospheric circulation. The Southern Hemisphere westerlies shifted poleward during each northern stadial, producing pulses of ocean upwelling and warming that together accounted for much of the termination in the Southern Ocean and Antarctica. Rising atmospheric C[O.sub.2] during southern upwelling pulses augmented warming during the last termination in both polar hemispheres. 10.1126/science.1184119

A study on the Ekman divergence and transport, which raises deep water from the ocean's interior around Antarctica, shows that the dynamic constraint operating in Drake Passage, connecting the Atlantic and the Pacific Ocean, facilitates the removal of water from the South Atlantic. The study utilized an ocean circulation model based on the GFDL Modular Ocean Model version 1.0 and the results showed that the strong winds in the south induce the formation of large amounts of water in the north causing a deep outflow through the South Atlantic. This may explain some new deep water formations in the North Atlantic.

There is an old truism in climate circles that the cold climate at the Last Glacial Maximum (LGM), which occurred 21,000 years ago, had stronger winds. This idea fits with [...]

Tyrrell has made a strong case that phosphorus, in the form of dissolved phosphate is the ultimate limiting nutrient of the ocean. Dissolved phosphate has the longest resident time of about 50,000 years, and Tyrrell built a simple model to describe relative abundances of nitrate and phosphate in the ocean, based on the ecological competition between phytoplankton that can fix N(sub2) from the air and those that cannot. However the model makes not provision for an important role for Fe.

A study of photosynthetic carbon uptake and flux of biogenic carbon in sinking particles in the ocean near Bermuda shows that dissolved inorganic carbon stocks increase in autumn and winter while they decrease during early autumn, spring and summer. However, only 20% of the downward flux of biogenic carbon in sinking particles could be detected and measured while 80% of carbon sinks could not be measured. This inadequacy can be due to the deficiency of sediment traps or due to the predominance of physical advection.

A study conducted by researchers Raymond Sambrotto et al on the drawdown of dissolved inorganic carbon, nitrate and phosphate during spring phytoplankton blooms revealed that the amount of carbon removed from the water is 10-14 times higher than that of nitrate. It also exceeds the amount predicted using Redfield ratios. Sambrotto tried to attribute this to the preferential recycling of nitrogen and phosphates as decomposition took place in detrital material. However, organic caarbon and nitrogen levels measured in marine particulate matter fail to prove a systematic bias for high C:N ratios. The form taken by the anomalous production remains to be clarified.

Three research papers have cast doubt on Y. Sugimura and Y. Suzuki's theory that high-temperature catalytic oxidation of dissolved organic carbon in ocean water produces far more carbon than previous wet-chemical oxidation methods. John H. Martin and Steve E. Fitzwater noticed no significant difference between the methods when they analysed samples of seawater. Hiroshi Ogawa, Norio Ogura and R. Benner achieved similar results. Researchers must now concentrate on whether gradients in the carbon cycle are real or merely artefacts of the method employed.