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Global glacier dynamics during 100 ka Pleistocene glacial cycles

Accepted version
Peer-reviewed

Type

Article

Change log

Authors

Hughes, PD 
Gibbard, PL 

Abstract

jats:titleAbstract</jats:title>jats:pIce volume during the last ten 100 ka glacial cycles was driven by solar radiation flux in the Northern Hemisphere. Early minima in solar radiation combined with critical levels of atmospheric COjats:sub2</jats:sub>drove initial glacier expansion. Glacial cycles between Marine Isotope Stage (MIS) 24 and MIS 13, whilst at 100 ka periodicity, were irregular in amplitude, and the shift to the largest amplitude 100 ka glacial cycles occurred after MIS 16. Mountain glaciers in the mid-latitudes and Asia reached their maximum extents early in glacial cycles, then retreated as global climate became increasingly arid. In contrast, larger ice masses close to maritime moisture sources continued to build up and dominated global glacial maxima reflected in marine isotope and sea-level records. The effect of this pattern of glaciation on the state of the global atmosphere is evident in dust records from Antarctic ice cores, where pronounced double peaks in dust flux occur in all of the last eight glacial cycles. Glacier growth is strongly modulated by variations in solar radiation, especially in glacial inceptions. This external control accounts for ~50–60% of ice volume change through glacial cycles. Internal global glacier–climate dynamics account for the rest of the change, which is controlled by the geographic distributions of glaciers.</jats:p>

Description

Keywords

Glaciation, orbital forcing, glacial cycles, ice sheets, glaciers, Pleistocene

Journal Title

Quaternary Research (United States)

Conference Name

Journal ISSN

0033-5894
1096-0287

Volume Title

Publisher

Cambridge University Press (CUP)