Tropical cooling and the onset of North American glaciation
We offer a test of the idea that gradual cooling in the eastern tropical Pacific led to cooling of North America and the initiation of glaciation ~3 Myr ago. Using modern climate data we estimate how warming of the eastern tropical Pacific affects North American temperature and ice-ablation. Ass...
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2007-09-01
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Series: | Climate of the Past |
Online Access: | http://www.clim-past.net/3/549/2007/cp-3-549-2007.pdf |
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doaj-5312ba7be0814f0491f442770b2100392020-11-24T23:22:30ZengCopernicus PublicationsClimate of the Past1814-93241814-93322007-09-0133549557Tropical cooling and the onset of North American glaciationP. HuybersP. MolnarWe offer a test of the idea that gradual cooling in the eastern tropical Pacific led to cooling of North America and the initiation of glaciation ~3 Myr ago. Using modern climate data we estimate how warming of the eastern tropical Pacific affects North American temperature and ice-ablation. Assuming that the modern relationship holds over the past millions of years, a ~4°C warmer eastern tropical Pacific between 3–5 Ma would increase ablation in northern North America by approximately two meters per year. By comparison, a similar estimate of the ablation response to variations in Earth's obliquity gives less than half the magnitude of the tropically-induced change. Considering that variations in Earth's obliquity appear sufficient to initiate glaciations between ~1–3 Ma, we infer that the warmer eastern equatorial Pacific prior to 3 Ma suffices to preclude glaciation. http://www.clim-past.net/3/549/2007/cp-3-549-2007.pdf |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
P. Huybers P. Molnar |
spellingShingle |
P. Huybers P. Molnar Tropical cooling and the onset of North American glaciation Climate of the Past |
author_facet |
P. Huybers P. Molnar |
author_sort |
P. Huybers |
title |
Tropical cooling and the onset of North American glaciation |
title_short |
Tropical cooling and the onset of North American glaciation |
title_full |
Tropical cooling and the onset of North American glaciation |
title_fullStr |
Tropical cooling and the onset of North American glaciation |
title_full_unstemmed |
Tropical cooling and the onset of North American glaciation |
title_sort |
tropical cooling and the onset of north american glaciation |
publisher |
Copernicus Publications |
series |
Climate of the Past |
issn |
1814-9324 1814-9332 |
publishDate |
2007-09-01 |
description |
We offer a test of the idea that gradual cooling in the eastern tropical Pacific led to cooling of North America and the initiation of glaciation ~3 Myr ago. Using modern climate data we estimate how warming of the eastern tropical Pacific affects North American temperature and ice-ablation. Assuming that the modern relationship holds over the past millions of years, a ~4°C warmer eastern tropical Pacific between 3–5 Ma would increase ablation in northern North America by approximately two meters per year. By comparison, a similar estimate of the ablation response to variations in Earth's obliquity gives less than half the magnitude of the tropically-induced change. Considering that variations in Earth's obliquity appear sufficient to initiate glaciations between ~1–3 Ma, we infer that the warmer eastern equatorial Pacific prior to 3 Ma suffices to preclude glaciation. |
url |
http://www.clim-past.net/3/549/2007/cp-3-549-2007.pdf |
work_keys_str_mv |
AT phuybers tropicalcoolingandtheonsetofnorthamericanglaciation AT pmolnar tropicalcoolingandtheonsetofnorthamericanglaciation |
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