by M. Floyd, June 13, 2019 in PhysOrg

Since scientists first determined that atmospheric carbon dioxide (CO₂) was significantly lower during ice age periods than warm phases, they have sought to discover why, theorizing that it may be a function of ocean circulation, sea ice, iron-laden dust or temperature.

Yet no computer model based on existing evidence has been able to explain why CO₂ levels were as much as one-third lower when an ice age settled in.

A new study published this week in Science Advances provides compelling evidence for a solution—the combination of sea water temperature variation and iron from dust off Southern Hemisphere continents.

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