Publications

Variability of the Intertropical Convergence Zone recorded in coral isotopic records from the central Indian Ocean (Chagos Archipelago)


Year
1
Source
Quaternary Research 61(3): 245-255.
Source type
journal_article
DOI
10.1016/j.yqres.2004.02.009
ISBN-13
0
Keywords
Variability of the Intertropical Convergence Zone recorded in coral isotopic records from the central Indian Ocean (Chagos Archipelago)
Link
http://www.sciencedirect.com/science/article/pii/S0033589404000407
Abstract
We have analyzed the stable oxygen isotopic composition of two Porites corals front the Chagos Archipelago, which is situated in the geographical center of the Indian Ocean. Coral 6180 at this site reliably records temporal variations in precipitation associated with the Intertropical Convergence Zone (ITCZ). Precipitation maxima occur in boreal winter, when the ITCZ forms a narrow band across the Indian Ocean. The Chagos then lies within the center of the ITCZ, and rainfall is strongly depleted in delta(18)O. A 120-yr coral isotopic record indicates an alternation of wet and dry intervals lasting 15 to 20 yr. The most recent 2 decades are dominated by interannual variability, which is tightly Coupled to the El Nino-Southern Oscillation (ENSO). This is unprecedented in the 120 yr of coral record. As the ITCZ is governed by atmospheric dynamics, this provides evidence of a major change in the coupled ENSO-monsoon system. (C) 2004 University of Washington. All rights reserved.
Clearance
0
Status
S
Authors
Pfeiffer M , Dullo W , Eisenhauer A .
Resources
Local link