Question

How does the ocean’s carbon dioxide (CO2) absorption affect the global climate?


CO2 absorption directly depletes the ozone layer.


CO2 absorption moderates the greenhouse effect by absorbing CO2 from the atmosphere.


CO2 absorption immediately increases atmospheric oxygen levels.


CO2 absorption significantly increases global temperatures in the short term.

Answer 1

Short answer: Only the second statement is essentially correct. Explanations:

- "CO2 absorption directly depletes the ozone layer." — False. Ozone depletion is caused mainly by halogenated chemicals (e.g., CFCs) and chemical reactions in the stratosphere. Ocean CO2 uptake does not directly destroy stratospheric ozone.

- "CO2 absorption moderates the greenhouse effect by absorbing CO2 from the atmosphere." — True (with caveats). The ocean is a major carbon sink (it has absorbed roughly 25–30% of human‑emitted CO2), which reduces the rise of atmospheric CO2 and thus moderates warming. However, this is not a perfect fix: the ocean’s uptake slows but does not stop climate change, can be overwhelmed, and becomes less effective as waters warm.

- "CO2 absorption immediately increases atmospheric oxygen levels." — False. Dissolving CO2 in seawater does not produce oxygen. Atmospheric O2 is produced mainly by photosynthesis (marine and terrestrial). Ocean CO2 uptake can be linked to biological activity that produces O2, but there is no immediate, direct oxygen increase from CO2 dissolution.

- "CO2 absorption significantly increases global temperatures in the short term." — False. Removing CO2 from the atmosphere tends to reduce, not increase, greenhouse forcing. That said, complex feedbacks exist (e.g., warmer oceans hold less CO2 and may release some back), but ocean uptake itself does not short‑term raise global temperatures.

Additional important point: ocean CO2 uptake causes ocean acidification, which harms marine life and ecosystems even while it moderates atmospheric warming.