Since the 1970s, there has been a growing global awareness of the El Niño–Southern Oscillation (ENSO) phenomenon, especially in regard to its impacts on humans, natural ecosystems, and agriculture. The three strongest events of these decades (1972–73, 1982–83, and 1997–98) each marked a milestone in this progression. To be sure, not all climate extremes during any given ENSO year are necessarily due to that phenomenon; for example, the intense drought that occurred in 1982–83 in the West African Sahel does not appear to be causally linked to the strong ENSO event of that period (Glantz, 1987). However, even unrelated climate anomalies can exacerbate the effects of an El Niño or La Niña on world food supplies. Here we summarize the major effects of the three most recent very strong El Niño events (see box 4.1) with a focus on their agricultural manifestations. Table 4.1 summarizes the effects by region and continent and for the world food system as a whole. Evolving understanding of ENSO (and its related phenomena) appears to be contributing to the development of improved resilience to such major climate shocks in some regions (see chapter 6 for use of ENSO predictions in agriculture and chapter 8 on building adaptive capacity). However, continuing progress in affected regions is needed for agriculture to withstand (or benefit from) very strong El Niño events in the future, especially since global climate change may be affecting conditions as well. The El Niño of 1972–73 awakened international attention to the ENSO cycle. Besides the failure of the fishery industry in Peru, there were droughts, floods, and food shortages in various locations around the world that also appeared to be associated with El Niño. Consequently, scientists and the public began to realize that El Niño teleconnections and their impacts could extend beyond the West Coast of South America (Glantz, 2001). During the El Niño event of 1972–73, the reduced anchoveta harvest, combined with overfishing, caused the collapse of the Peruvian fishmeal industry and the dislocation of entire fishing communities.
Shelf Fish Larval Abundance Along the West Coast of Baja California During a Period with two El Niño Events 1983-1987
