Biogeochemical context impacts seawater pH changes resulting from atmospheric sulfur and nitrogen deposition. Issue 3 (7th February 2014)

• Record Type: Journal Article
• Authors: Hagens, Mathilde; Hunter, Keith A.; Liss, Peter S.; Middelburg, Jack J.
• Is Part Of: Geophysical research letters. Volume 41:Issue 3(2014:Feb.)
• Page Start: 935
• Page End: 941
• Publication Date: 2014-02-07
• Subjects: Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2013GL058796
• Languages: English
• ISSNs: 0094-8276

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>Seawater acidification can be induced both by absorption of atmospheric carbon dioxide (CO₂) and by atmospheric deposition of sulfur and nitrogen oxides and ammonia. Their relative significance, interplay, and dependency on water column biogeochemistry are not well understood. Using a simple biogeochemical model we show that the initial conditions of coastal systems are not only relevant for CO₂‐induced acidification but also for additional acidification due to atmospheric acid deposition. Coastal areas undersaturated with respect to CO₂ are most vulnerable to CO₂‐induced acidification but are relatively least affected by additional atmospheric deposition‐induced acidification. In contrast, the pH of CO₂‐supersaturated systems is most sensitive to atmospheric deposition. The projected increment in atmospheric CO₂ by 2100 will increase the sensitivity of coastal systems to atmospheric deposition‐induced acidification by up to a factor 4, but the additional annual change in proton concentration is at most 28%.</p> </abstract>