GEOL 3070 Lecture Notes - Lecture 22: Upwelling, Ocean Gyre, Aragonite

• School: CU-Boulder
• Department: Geological Sciences
• Course: GEOL 3070
• Professor: Thomas Marchitto

Document Summary

One of the 7 major elements in seawater. Relative abundance of dic species is related to ph. Pure water: a tiny fraction of h2o dissociates into hydrogen (h+) and hydroxide (oh-) Since h2o is the only source of these ions in pure water, their abundances must be equal. [h+] = [oh-] = 10-7 mol/kg ph= -log[h+] = 7 for pure water (neutral) Seawater: [h+] & [oh-] are imbalanced because of the presence of numerous other ions that consumer or release [h+] or [oh-] [h+] is less abundant and [oh-] is more abundant. Seawater ph is slightly basic --> ph ~7. 5-8. 5. **presence of hydrogen (h+) makes things more basic & vice versa** Higher ph at the surface, lower ph at depth. B. ph is affected by co2 (natural & anthropogenic) C02 + h2o --> h2co3 --> h+ + hco3. C02 addition: most (but not all) c02 becomes carbonic acid which dissociates into h+