The Paleocene-Eocene Thermal Maximum - A "super greenhouse" catastrophe 55 million years ago
Superimposed on this, for a period of about 100 000 years, extraordinarily warm conditions developed at the Paleocene-Eocene (P-E) boundary 55 million years ago. Oxygen isotopic studies show that surface-waters off Antarctica warmed from about 13 °C to 20 °C. Subtropical regions also became warmer, but the higher the latitude the greater was the effect.
Some of the most dramatic biotic changes of the Cenozoic coincide with this event. The warming is accompanied by the largest carbon isotopic excursion of the Cenozoic, reflecting a rapid flooding of the atmosphere by CO2, possibly from sea-floor methane hydrates or organic-rich sediments heated by volcanic lava.
In our group we perform detailed studies of this greenhouse catastrophe since it represents an analogue to the ongoing global warming and rising CO2. Our studies of the P-E boundary in continental sedimentary rocks in Spain (see Fig 1) indicate dramatic increases in seasonal extreme precipitation events during the most intense phase of CO2 enrichment in the atmosphere. This is in accord with predicted dramatic changes in the hydrological cycle in dry subtropical regions when CO2 in the present world continues to rise.
At the present we study in particular the flux of minerogenic particles to land-distal deep-sea environments during the culmination of the super greenhouse event. This may give information of how the wind system behaved, but will also give information as to whether any unique kind of volcanic or extraterrestrial event contributed dust to the atmosphere during the greenhouse catastrophe.