Effect of El Nino-Southern Oscillation on Annual Maximum Flood in Southwestern of Iran

Document Type : Research Paper


1 Former Research Associate, Soil Conservation and Watershed Management Research Institute

2 Assoc. Prof., Soil Conservation and Watershed Management Research Institute


Flood forecasting and the study of the factors involved in flood events form important issues of concern in water resources management. In recent years, the influence of large-scale global climate phenomena on flood peaks has attracted more attention. In this paper, the effect of El Nino-Southern Oscillation (ENSO) is investigated on annual maximum flood (AMF) in Iran’s southwestern basins. The basins are located upstream of Dez and Karun-I dams. ENSO effects on probability, magnitude, and intensity (probability times magnitude) of AMF in the Esfand-Farvardin (March-April) period are examined. The results indicate that following El Nino, the probability of an AMF occurrence larger than the AMF corresponding to neutral ENSO conditions is higher in the study period. The opposite is true for La Nina conditions. It is also seen that El Nino effects are more intense than those of La Nina period.


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شماره 64 سال 1386                                                                                                                        آب و فاضلاب
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