Are the 41kyr Glacial Oscillations a Linear Response to Milankovitch Forcing?

DSpace/Manakin Repository

Are the 41kyr Glacial Oscillations a Linear Response to Milankovitch Forcing?

Show simple item record Ashkenazy, Yosef Tziperman, Eli 2009-12-08T18:42:59Z 2004
dc.identifier.citation Ashkenazy, Yosef, and Eli Tziperman. 2004. Are the 41kyr glacial oscillations a linear response to Milankovitch forcing? Quaternary Science Reviews 23(18-19): 1879-1890. en_US
dc.identifier.issn 0277-3791 en_US
dc.description.abstract The characteristics of glacial oscillations changed drastically ~0.8Ma ago, at the ‘‘mid-Pleistocene transition’’. During the past 0.8Ma the ~100 kyr glacial–interglacial oscillations were strongly asymmetric (i.e., long glacial intervals of growth followed by rapid intervals of deglaciation). The 40 kyr oscillations prior to the mid-Pleistocene transition were of a smaller amplitude and less-asymmetrical looking. The smaller amplitude, apparently symmetric form and period that matches that of obliquity, suggests that these oscillations were a linear response to Milankovitch forcing, while the 100 kyr oscillations are attributed either to some nonlinear self-sustained variability due to a mechanism internal to the climate system itself or to nonlinear amplification of the insolation forcing. The significant strengthening of the 100 kyr eccentricity power in the past ~800 kyr is one of the intriguing questions of climate history. Here we show that glacial–interglacial oscillations pre-mid-Pleistocene transition are, in fact, significantly asymmetric. This asymmetry may contradict a straight forward linear Milankovitch explanation, and we therefore suggest that the glacial oscillations before and after the transition may both be explained as self-sustained variability (although the possibility of nonlinear response to insolation forcing still exists). The role of Milankovitch forcing is in setting the phase of the oscillations (e.g. time of terminations) and their period, rather in being the main driving force of the oscillations. This is demonstrated using a simple model based on the sea ice switch mechanism of Gildor and Tziperman (Paleoceanography 15 (2000) 605). en_US
dc.description.sponsorship Earth and Planetary Sciences en_US
dc.language.iso en_US en_US
dc.publisher Elsevier en_US
dc.relation.isversionof en_US
dash.license META_ONLY
dc.title Are the 41kyr Glacial Oscillations a Linear Response to Milankovitch Forcing? en_US
dc.type Journal Article en_US
dc.description.version Version of Record en_US
dc.relation.journal Quaternary Science Reviews en_US Tziperman, Eli
dash.embargo.until 10000-01-01

Files in this item

Files Size Format View
Tziperman_OscillatMilankoForcing.pdf 460.1Kb PDF View/Open

This item appears in the following Collection(s)

Show simple item record


Search DASH

Advanced Search