Figure 6a is a photograph that shows a German research vessel and icebreaker Polarstern off the Antarctic Peninsula in February 1994. The Polarstern was used for ocean fertilisation experiments such as EIFEX and LOHAFEX.
Figure 6b shows a satellite image of the northern Pacific ocean, with an arc of bright cyan (labelled iron fertilisation bloom?) across the middle of the image, across a darker blue or green background for the rest of the scene; the date August 12 2012 is shown.
Figure 6c is a colour coded image of the same region and time as figure 6b (north Pacific) and shows 'Chlorophyll' concentration anomalies. Most of the scene has anomalies in the range (-1.6 - +1.6) milligrams per meter cubed; there are small patches in the top-right and bottom left showing increases as high as over 4 milligrams per meter cubed.