Estimates for the amount of man-made CO2 absorbed by the oceans is estimated at around 30 > 40%. The processes which govern the rate of absorption are extremely complex and poorly understood.
• As the ocean warms, its capacity to absorb CO2 decreases, tending to release pre-dissolved gases as the temperature rises.
• Warmer oceans lead to increasingly unstable weather patterns and windspeeds which mean higher waves and more sea-spray bubbles - affecting the absorption ( and release ) of CO2
• As the temperature rises, sea plants and microorganisms which absorb CO2 become more prolific.
Recent measurements of oceanic CO2 have not followed the 'expected' rates - so the carbon-sink model must be inaccurate in some as-yet-unknown way(s).
Despite the importance of the ocean carbon sink to climate, our understanding of the causes of its interannual‐to‐decadal variability remains limited. This hinders our ability to attribute its past behavior and project its future. A key period of interest is the 1990s, when the ocean carbon sink did not grow as expected.
Source: AGU Advances
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