UKOARP Theme E: Abrupt ocean acidification events [and their effects in the Earth's past]
One way to predict the future is to study similar events in the geological past. The geological record contains a number of abrupt events where acidification increased rapidly in response to natural emissions (the largest being the Paleocene / Eocene thermal maximum event, 55 million years ago). So far the acidification during these events has not been measured adequately and details of the way marine life was affected have not been fully investigated.
This theme will investigate a variety of geological records from the deep sea and the margins of the oceans. Unique among these being a newly recovered borehole through marine sediments in Tanzania. Preliminary work revealed the presence of a highly expanded (thick) record of the onset of the Paleocene / Eocene thermal maximum (PETM) event with very well-preserved planktonic microfossils that is suitable for new geochemical and biological studies.
This theme addresses the following specific aims:
- To produce new estimates of seawater acidity and atmospheric carbon dioxide levels for the period 65-40 million years ago
- To study the response of the carbon cycle during the rapid onset of the PETM using new data from Tanzania and elsewhere and new computer models
- To compare the PETM with other known smaller ocean acidification events in the Earth's past
- To quantify the biotic response to ocean acidification events both directly (speciation, extinction, migration, malformation , etc.) and indirectly (ecosystem function, biogeochemical cycles)
Weblink: http://www.ocean-acidification.org.uk/project_objectives/historic_events.aspx