252 Ecological Sustainability
H CO H HCO (bicarbonate ion)
2 3 3
↔ +
+ −
(4.61)
4. Second ionization:
HCO H CO (carbonate ion)
3 3
2− + −
↔ + (4.62)
Note that the H
+
ions from reactions 3 and 4 above lower the oceans’ pH
(acidify it). The carbon dioxide storage sensitivity of the ocean is 0.1%/%; that
is, a 10% increase in atmospheric CO
2
causes an approximately 1% increase
in total ocean storage of carbon as H
2
CO
3
,
, plus
. The bicarbonate
and carbonate ions are taken up by plankton, mollusks, and crustaceans to
form shells, and they slowly react chemically with dissolved minerals.
At present, human sequestration of atmospheric CO
2
from diffuse sources
is under consideration. The worldwide anthropogenic CO
2
emitted by moto ...