Biological-physical coupling in the
Pacific during the 1997-98 El Niņo
Peter Strutton, Ph.D.
Monterey Bay Aquarium Research Institute
Friday, April 3, 1998
12:00 NoonPacific Forum
In late 1996, MBARI deployed bio-optical and chemical instrumentation on two moorings
in the central equatorial Pacific to monitor the biological changes associated with El
Niņo, as well as validate ocean-color satellites. By combining bio-optical and physical
time series, we were able to describe the physical progression of El Niņo onset, from
reversal of the trade winds in the western equatorial Pacific, through eastward
propagation of equatorially trapped Kelvin waves and advection of waters from the
nutrient-poor western equatorial warm pool. The physical perturbations were tightly
coupled to fluctuations in phytoplankton biomass and quantum yield of fluorescence.
Our data suggest that primary productivity in the central equatorial Pacific was
reduced to 50% of the climatological mean with the onset of the current El Niņo event.
the deep ocean
Last updated: December 19, 2000