Temporal variability in the northern Arabian Sea oxygen minimum zone (OMZ) during the last 225,000 years
Article first published online: 4 MAY 2010
Copyright 1998 by the American Geophysical Union.
Volume 13, Issue 6, pages 607–621, December 1998
How to Cite
1998), Temporal variability in the northern Arabian Sea oxygen minimum zone (OMZ) during the last 225,000 years, Paleoceanography, 13(6), 607–621, doi:10.1029/98PA02203., , and (
- Issue published online: 4 MAY 2010
- Article first published online: 4 MAY 2010
- Manuscript Accepted: 1 JUL 1998
- Manuscript Received: 13 MAR 1998
The northern Arabian Sea is one of the few regions in the open ocean where thermocline water is severely depleted in oxygen. The intensity of this oxygen minimum zone (OMZ) has been reconstructed over the past 225,000 years using proxies for surface water productivity, water column denitrification, winter mixing, and the aragonite compensation depth (ACD). Changes in OMZ intensity occurred on orbital and suborbital timescales. Lowest O2 levels correlate with productivity maxima and shallow winter mixing. Precession-related productivity maxima lag early summer insolation maxima by ∼6 kyr, which we attribute to a prolonged summer monsoon season related to higher insolation at the end of the summer. Periods with a weakened or even non-existent OMZ are characterized by low productivity conditions and deep winter mixing attributed to strong and cold winter monsoonal winds. The timing of deep winter mixing events corresponds with that of periods of climatic cooling in the North Atlantic region.