English: Change in ocean conditions from the last interglacial to the modern day
Schematic models showing subarctic north-west Pacific Ocean conditions for (a) modern day: halocline water column with nutrient poor surface waters limiting biological export; (b) MIS 5e: no halocline and enhanced upwelling of nutrient- and carbon-rich sub-surface waters leading to increased productivity. Low rates of nutrient utilisation suggest a possible increase in pCO2 and release of CO2 to the atmosphere; (c) MIS 5b/c: conditions similar to MIS 5e but with higher rates of nutrient consumption and a more efficient soft-tissue biological pump limiting/preventing ventilation of CO2.