Orbital Forcing - Cenozoic and Mesozoic
Our understanding of the role orbital forcing plays in Plio-Pleistocene climate change focuses on the role of ice.
Changes in ice volume provide most of the signal in d18O curves, provide one clear positive feedback loop (ice-albedo feedback), and explain repetitive stratigraphic packages of onlap and offlap. However, for much of the Cenozoic and Mesozoic, ice was confined to either the Antarctic region, or not present in any large amounts anywhere on the globe. What happened in the absence of ice feedbacks? The evidence strongly suggests that Milankovitch cycles can be found in the sedimentary record at all times. Much of my work involves generating and analyzing sedimentary time series of Cenozoic and Mesozoic age to establish this point.
Brown faculty collaborators:John Mustard
Other project collaborators:Christopher Cooper
Example of middle Cretaceous precessional climate cycles from the South Atlantic (DSDP Site 516F).Back to Timothy Herbert's Brown Research Profile