A conceptual model for the temporal spectrum of oceanic oxygen variability
Article first published online: 2 FEB 2010
Copyright 2010 by the American Geophysical Union.
Geophysical Research Letters
Volume 37, Issue 3, February 2010
How to Cite
2010), A conceptual model for the temporal spectrum of oceanic oxygen variability, Geophys. Res. Lett., 37, L03601, doi:10.1029/2009GL041595., and (
- Issue published online: 2 FEB 2010
- Article first published online: 2 FEB 2010
- Manuscript Accepted: 4 JAN 2010
- Manuscript Revised: 21 DEC 2009
- Manuscript Received: 3 NOV 2009
 Changes in dissolved O2 observed across the world oceans in recent decades have been interpreted as a response of marine biogeochemistry to climate change. Little is known however about the spectrum of oceanic O2 variability. Using an idealized model, we illustrate how fluctuations in ocean circulation and biological respiration lead to low-frequency variability of thermocline oxygen. Because the ventilation of the thermocline naturally integrates the effects of anomalous respiration and advection over decadal timescales, short-lived O2 perturbations are strongly damped, producing a red spectrum, even in a randomly varying oceanic environment. This background red spectrum of O2 suggests a new interpretation of the ubiquitous strength of decadal oxygen variability and provides a null hypothesis for the detection of climate change influence on oceanic oxygen. We find a statistically significant spectral peak at a 15–20 year timescale in the subpolar North Pacific, but the mechanisms connecting to climate variability remain uncertain.