The E1 Niño/Southern Oscillation (ENSO) climate pattern in the southern Pacific is known to affect global rainfall patterns with direct impacts on agriculture and fishing industries. Previously, a long- term historical database of monthly rainfall for stations around the world was analyzed. For each station and Southern Oscillation Index (SOI) phase, the probabilities of obtaining amounts of seasonal rainfall relative to the median at the station were calculated. These data were interpolated so there for each SOI phase determined over two months, rainfall forecasts are made for the coming three-month period. In this paper, we further interpret those results and look for relationships among locations. A consistently negative SOI in May/June is one of the strongest signals. It forecasts only a 10 to 30% chance of achieving median rainfall (i.c., high probability of drought)for July to September in eastern Australia, south Asia, south-east Asia, west Africa, Central America and northern Brazil. This same signal predicts greater than median rainfall in the USA, central Asia and the Southern Cone of South America. Another strong signal during the same period is a consistently positive SOI, and it often forecasts virtually the opposite situation. Knowing the SOI phase prior to planting, the likelihood of receiving a good, average or poor season can be forecast. On a global basis, this knowledge has application for decision-making on-farm and in marketing and policy formation.

English

9801|AGRIS 9702

Jose Juan Caballero

CIMMYT Publications Collection