Ocean Acidification - A Paleo Perspective

Abstract

Dissolution of atmospheric CO₂ in seawater has lowered ocean pH and carbonate ion concentrations with impacts on marine organisms and ecosystems. The geological record contains long-term evidence for a variety of global environmental perturbations, including ocean acidification, and the biotic responses associated with them, and can provide insight into consequences of current anthropogenic acidification. This e-lecture focuses on the paleo-perspective of ocean acidification, proxy evidence for pH changes and several events exhibiting evidence for elevated atmospheric CO₂, global warming, and ocean acidification over the past ˜300 million years are reviewed. Comparison between these events and the present suggests that the current and projected rate of acidification may be unprecedented in past events with unknown consequences for marine life and humans who depend on it.

The target audiences for this e-Lecture are upper division undergraduate students and graduate students with some previous background in oceanography and paleoceanography. This could be a lecture in an “introduction to paleoceanography” class that discusses archives and proxies or a lecture in a topical “ocean acidification” class covering paleo ocean acidification. Depending on audience background the lecture may take 50 minutes (students versed in paleoceanography) or 90 minutes (novice students).