Identification:
Title:
Changes in atmospheric circulation during the latest Paleocene and earliest Eocene epochs and some implications for the global climate regime
Year:
1998
Source:
In: Aubry, Marie-Pierre (editor), Lucas, Spencer G. (editor), Berggren, William A. (editor), Late Paleocene-early Eocene climatic and biotic events in the marine and terrestrial records
Publisher:
Columbia University Press, New York, NY, United States
Volume:
Issue:
Pages:
118-123
Abstract:
Examination of eolian sediments from deep-sea cores has revealed evidence for a significant reduction in the intensity of atmospheric circulation that occurred over a span of 1-2 my in the temporal vicinity of the Paleocene/Eocene Epoch boundary. Early Eocene winds were much more sluggish than the surprisingly strong winds of the latest Cretaceous Period and Paleocene Epoch, and implicate a significant reduction in the planetary temperature gradient. In a sequence of longer-term changes that occurred over approximately 3 my beginning in the late Paleocene Epoch (from Biochron P4 to P6), the onset of ocean deep-water warming (based on delta (super 18) O data) preceded the beginning of changes in the partitioning of carbon between ocean and sedimentary reservoirs (based on delta (super 13) C data), which preceded the start of a pronounced reduction in wind intensity, which preceded the benthic foraminifera extinction. These four events were spaced roughly one-half to one million years apart. Explanations for this rather drawn-out series of changes, particularly considering the order in which they occur, are not yet fully satisfactory. The introduction to the ocean-atmosphere system of another greenhouse gas, methane, may be more important than previously considered.
Language:
English
Genre:
Book
Rights:
URL: