Abstract
The El Niño–southern oscillation phenomenon (ENSO) is one of the principal sources of interannual climatic variability. In Argentina, the ENSO signal is evident both in climate and crop yields. As ENSO phases (El Niño, La Niña, Neutral) can actually be predicted several months before their occurrence, the use of ENSO‐based climate forecasts as tools to assist farmers in decision making has recently been proposed. However, the use of ENSO‐phases could be insufficient for planning in the agricultural sector due to the signal interannual intra‐phase variability. Moreover, the observed spatial variability in the ENSO signal suggests the existence of other factors that influence the local climate and crop responses in the region. Looking for alternative indicators of climate variability other than ENSO phases, monthly sea‐surface temperature (SST) anomalies from the equatorial Pacific and the South Atlantic Oceans were related to maize and wheat yield anomalies in the main crop‐producing zone of the Pampas region. In general, yield anomalies were better correlated with SST anomalies occurring in the months prior to sowing. This indicator could be a useful tool to ascertain what range of yields could be expected with sufficient anticipation so as to modify crop management decisions. Copyright © 2003 Royal Meteorological Society