This image shows the prominent green streak -- indicating a cooler temperature -- that is prominent in non-El Nino years. The green swirl extends westward from the coast of South America. This image was taken in May, 1988. Cooler temperatures are also seen in the central equatorial Pacific and in the equatorial Indian Ocean. (From Figure 6.6 in Parkinson, pg. 91, Earth from Above, Using Color-Coded Satellite Images to Examine the Global Environment.)