In:
Science Advances, American Association for the Advancement of Science (AAAS), Vol. 5, No. 12 ( 2019-12-06)
Abstract:
Atmospheric greenhouse gas concentrations are thought to have synchronized global temperatures during Pleistocene glacial–interglacial cycles, yet their impact relative to changes in high-latitude insolation and ice-sheet extent remains poorly constrained. Here, we use tropical glacial fluctuations to assess the timing of low-latitude temperature changes relative to global climate forcings. We report 10 Be ages of moraines in tropical East Africa and South America and show that glaciers reached their maxima at ~29 to 20 ka, during the global Last Glacial Maximum. Tropical glacial recession was underway by 20 ka, before the rapid CO 2 rise at ~18.2 ka. This “early” tropical warming was influenced by rising high-latitude insolation and coincident ice-sheet recession in both polar regions, which lowered the meridional thermal gradient and reduced tropical heat export to the high latitudes.
Type of Medium:
Online Resource
ISSN:
2375-2548
DOI:
10.1126/sciadv.aaw2610
Language:
English
Publisher:
American Association for the Advancement of Science (AAAS)
Publication Date:
2019
detail.hit.zdb_id:
2810933-8
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