More "settled" science: Disagreement about "what controls where and how CO2 comes out of the ocean"

Rutgers Researchers Find a ‘Great Fizz’ of Carbon Dioxide at the End of the Last Ice Age

Imagine loosening the screw-top of a soda bottle and hearing the carbon dioxide begin to escape. Then imagine taking the cap off quickly, and seeing the beverage foam and fizz out of the bottle. Then, imagine the pressure equalizing and the beverage being ready to drink.

Rutgers marine scientist Elisabeth Sikes and her colleagues say that something very similar happened on a grand scale over a 1,000 year period after the end of the last ice age – or glaciation, as scientists call it.
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In recent years, other researchers have suggested that some of that carbon dioxide flowed back into the northern hemisphere rather than being entirely released into the atmosphere in the southern hemisphere.

Sikes and her colleagues disagree. Their data, taken from cores of ocean sediment pulled up from 600 meters to 1,200 meters below the South Pacific and Southern Ocean, suggest that this “de-gassing” was regional, not global. This has important implications for understanding what controls where and how CO2 comes out of the ocean, and how fast – or, to put it another way, what tightens or loosens the bottle cap.
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The ventilation of the deep Southern Ocean – the circulation of oxygen through the deep waters – slowed considerably during the last ice age, causing carbon dioxide to build up. Sikes and her co-authors report that, as the ice began to melt, the oceanic bottle cap began to loosen, and the carbon dioxide began to leak back into the atmosphere. Then, as warming intensified, the cap came off, and the carbon dioxide escaped so quickly, and so thoroughly, that Sikes and her colleagues could find very little trace of it in the carbon 14 they examined in their samples.

If this "fizzing" event occurred, why didn't allegedly positive feedbacks cause the Earth to become an uninhabitable fireball?