In:
Science, American Association for the Advancement of Science (AAAS), Vol. 334, No. 6060 ( 2011-12-02), p. 1261-1264
Abstract:
Earth’s modern climate, characterized by polar ice sheets and large equator-to-pole temperature gradients, is rooted in environmental changes that promoted Antarctic glaciation ~33.7 million years ago. Onset of Antarctic glaciation reflects a critical tipping point for Earth’s climate and provides a framework for investigating the role of atmospheric carbon dioxide (CO 2 ) during major climatic change. Previously published records of alkenone-based CO 2 from high- and low-latitude ocean localities suggested that CO 2 increased during glaciation, in contradiction to theory. Here, we further investigate alkenone records and demonstrate that Antarctic and subantarctic data overestimate atmospheric CO 2 levels, biasing long-term trends. Our results show that CO 2 declined before and during Antarctic glaciation and support a substantial CO 2 decrease as the primary agent forcing Antarctic glaciation, consistent with model-derived CO 2 thresholds.
Type of Medium:
Online Resource
ISSN:
0036-8075
,
1095-9203
DOI:
10.1126/science.1203909
Language:
English
Publisher:
American Association for the Advancement of Science (AAAS)
Publication Date:
2011
detail.hit.zdb_id:
128410-1
detail.hit.zdb_id:
2066996-3
detail.hit.zdb_id:
2060783-0
SSG:
11
