The Galápagos Islands, off the coast of Ecuador, are in an oceanic transition zone between the central and eastern equatorial Pacific. The islands are directly affected by both weak and strong El Nino events, whether the warm water initially forms in the central Pacific and moves toward the east coast of Ecuador and Peru, or whether it form along the coastal area and movers toward the central Pacific.
In 1983, the meteorological station of the Charles Darwin Research Station (CDRS) recorded the total precipitation for 1983 was 2768.7mm (Glynn, 1990). This is compared with normal years in which measurable precipitation averages 361 mm (excluding values from 1983, 1997-98). On the other hand, the total precipitation for El Niño 97-98 was also unusually high (3407.6mm). Figure 1 shows the notable peak which occurred in 1983, during which El Niño reached its greatest intensity.
Figure 1. Annual precipitation measured at the Charles Darwin Research Station (CDRS), 1965 – 2010. Source: CDRS (2011)
The mean monthly sea surface temperature measured by the same station reached 28.6 Celsius in the mouth of March 1983 compared to normal years in which the mean temperature of this month is 23.3 Celsius (excluding values from 1982-83, 1997-98). Figure 2 displays mean annual sea surface temperatures observed at the CDRS between 1965 and 2010. The peak observed in 1983 and 1997 is clearly visible and 1997’s is the highest mean annual sea temperature observed during 55 years of observations. Figure 3 shows the changes in mean annual air temperature observed at the CDRS. Again, high temperatures peaked in 1998 (or 1983), when the annual mean was 23.8 Celsius, compared with an average annual mean of 23.8 Celsius in normal years (excluding values from 1982-83, 1997-98).
Figure 2. Mean annual sea surface temperature measured at the CDRS, 1965 – 2010. Source: CDRS (2010)
Figure 2. Mean annual air temperature measured at the CDRS, 1965 – 2010. Source: CDRS (2010)