Ocean carbon ‘major blind spots’ may (or must?) skew climate forecasts

The oceanic carbon cycle [credit: IAEA]

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After decades of peddling carbon dioxide scares – this ‘glaring uncertainty’ emerges. We read: ‘Climate models built on incomplete data’. Hardly news, in general terms, as that’s one reason for having models in the first place. But if ‘major blind spots remain in our scientific understanding of this process’ (ocean carbon storage), with significant discrepancy levels cited (10-20%, sometimes more) any attempt to use climate models for government policy must surely be flawed from the start.
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A new report by the Intergovernmental Oceanographic Commission (IOC) of UNESCO reveals a critical lack of understanding of how the ocean absorbs and stores carbon, says Phys.org.

This glaring uncertainty about our planet’s largest carbon sink threatens to skew current climate predictions, and hamper our ability to develop effective mitigation and adaptation strategies in the coming decades.

The report also lays out a roadmap to bolster international cooperation, strengthen ocean carbon monitoring and update climate models accordingly.

“The ocean is one of our strongest climate allies, absorbing a large share of the carbon we emit,” said Khaled El-Enany, UNESCO Director-General. “Yet we still lack a full understanding of how this natural defense functions—or how long it can endure. Coordinated global monitoring of ocean carbon absorption is therefore essential and urgent.

“This report reaffirms UNESCO’s commitment to supporting Member States in developing climate policies based on robust science to advance this goal.”

The ocean is storing around 25% of global CO₂ emissions. But according to the new report coordinated by IOC-UNESCO, major blind spots remain in our scientific understanding of this process, with variations large enough to considerably affect how governments plan climate mitigation and adaptation strategies.

The Integrated Ocean Carbon Research Report finds that scientific models differ widely in estimating how much carbon the ocean absorbs, with discrepancies of 10%–20% globally and even greater in certain regions.

These differences stem from limited availability of long-term data, and gaps in understanding how key processes respond to climate change.

This means quantifying how changes in ocean warming and circulation affect carbon uptake, how shifts in plankton and microbial life influence long-term storage, and how coastal and polar regions exchange carbon with the atmosphere.

Industrial activities today, and the risks associated with climate engineering in the future may also alter the ocean’s natural ability to absorb carbon.

Major implications for climate targets and adaptation
All of this indicates that we are making climate decisions without knowing how the ocean will behave.
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From uncertainty to action
Prepared by 72 authors across 23 countries, the Integrated Ocean Carbon Research Report offers the most comprehensive synthesis to date of the uncertainties affecting the ocean carbon sink.

Beyond identifying research needs, the report also lays out a coordinated roadmap to strengthen monitoring, modeling and international cooperation so that ocean carbon science can more directly inform climate policy.

Full article here.
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Image: The oceanic carbon cycle [credit: IAEA]