Details

Autor(en) / Beteiligte

• Herbert, Timothy D
• Peterson, Laura Cleaveland
• Lawrence, Kira T
• Liu, Zhonghui

Titel

Tropical Ocean Temperatures Over the Past 3.5 Million Years

Ist Teil von

• Science (American Association for the Advancement of Science), 2010-06, Vol.328 (5985), p.1530-1534

Ort / Verlag

Washington, DC: American Association for the Advancement of Science

Erscheinungsjahr

2010

Link zum Volltext

Quelle

American Association for the Advancement of Science

Beschreibungen/Notizen

• Determining the timing and amplitude of tropical sea surface temperature (SST) change is an important part of solving the puzzle of the Plio-Pleistocene ice ages. Alkenone-based tropical SST records from the major ocean basins show coherent glacial-interglacial temperature changes of 1° to 3°C that align with (but slightly lead) global changes in ice volume and deep ocean temperature over the past 3.5 million years. Tropical temperatures became tightly coupled with benthic δ¹⁸O and orbital forcing after 2.7 million years. We interpret the similarity of tropical SST changes, in dynamically dissimilar regions, to reflect "top-down" forcing through the atmosphere. The inception of a strong carbon dioxide-greenhouse gas feedback and amplification of orbital forcing at approximately 2.7 million years ago connected the fate of Northern Hemisphere ice sheets with global ocean temperatures since that time.