PubMed HealthSearch

Biomedical subjects

PN Pearson

Publications and source records attributed to PN Pearson.

2 recordsLinked to original sources

Middle eocene seawater pH and atmospheric carbon dioxide concentrations

The carbon dioxide content of the atmosphere [measured as the partial pressure of CO2 (pCO2)] affects the content of the surface ocean, which in turn affects seawater pH. The boron isotope composition (delta11B) of contemporaneous planktonic foraminifera that calcified their tests at different water depths can be used to reconstruct the pH-depth profile of ancient seawater. Construction of a pH profile for the middle Eocene tropical Pacific Ocean shows that atmospheric pCO2 was probably similar to modern concentrations or slightly higher.

Journal Article

Reconstructing past ocean pH-depth profiles

Measurement of boron isotope compositions in species of planktonic foraminifera that calcified their tests at different depths in the water column are used to reconstruct the pH profile of the upper water column of the tropical ocean. Results for five time windows from the middle Miocene to the late Pleistocene indicate pH-depth profiles similar to that of the modern ocean in this area, which suggests that this method may greatly aid in our understanding of the global carbon cycle.

Journal Article