Orbital controls on the El Niño/Southern Oscillation and the tropical climate
Article first published online: 4 MAY 2010
Copyright 1999 by the American Geophysical Union.
Volume 14, Issue 4, pages 441–456, August 1999
How to Cite
1999), Orbital controls on the El Niño/Southern Oscillation and the tropical climate, Paleoceanography, 14(4), 441–456, doi:10.1029/1999PA900013., , and (
- Issue published online: 4 MAY 2010
- Article first published online: 4 MAY 2010
- Manuscript Accepted: 26 FEB 1999
- Manuscript Received: 8 OCT 1998
The global synchroneity of glacial-interglacial events is one of the major problems in understanding the link between Milankovitch forcing and the climate of the late Quaternary. In this study we isolate a part of the climate system, the tropical Pacific, and test its sensitivity to changes in solar forcing associated with changes in the Earth's orbital parameters. We use a simplified coupled ocean-atmosphere model that is run for the past 150,000 years and forced with Milankovitch changes in the solar insolation. This system responds primarily to the precessional cycle in solar forcing and is capable of generating a mean response to the changes in the seasonal distribution of solar radiation even while the annual mean insolation is roughly constant. The mean response to the precessional forcing is due to an interaction between an altered seasonal cycle and the El Niño/Southern Oscillation (ENSO). Changes in the ENSO behavior result in a mean tropical climate change. The hypothesis is advanced that such a change in the tropical climate can generate a globally synchronous climate response to Milankovitch forcing.