Anomalous Blooms in the Eastern Tropical South Pacific

A few months ago, I posted a series of images showing anomalous phytoplankton blooms just south of the Equator in the Pacific Ocean. Another look at the Aqua-MODIS chlorophyll composite reveals similar blooms about 4700 kilometers farther southeast or about 1500 kilometers southwest of Peru (top right image).

As in the case of the sub-equatorial blooms, these blooms are far from land in waters that, typically, have a much lower chlorophyll concentration.

Also similar to the other case is the fact that these blooms only appear for a few days each during a single year. In this case the year is 2005. You can see this by watching the animation below the chlorophyll color scale on the right. (Bloom chlorophyll concentrations appear higher in the 2005 composite than in the mission-length composite because fewer of the more typical low-chlorophyll measurements have been averaged into the 2005 composite than into the mission-length composite.)

The fact that measurements made on a single day can sometimes have significant impacts on long term averages can be seen on the next page.

5-year Aqua-MODIS chlorophyll composite standard chlorophyll color scale 5 separate years of Aqua-MODIS chlorophyll