EL-NINO PHENOMENON UPDATE

During El Nino events, the temperatures over the central and eastern tropical Pacific Ocean become significantly warmer than normal. On the other hand, during La Nina events, the ocean temperatures become colder than normal. Such temperatures are responsible for the major global climate changes that we have become accustomed to.

By the end of July 2002, features of the ocean and atmosphere signify the presence of weak-to-moderate El Nino conditions in the eastern and central Pacific since the beginning of the year. Based on numerical and statistical model forecasts, there are signs of a slow development of weak El Nino (warm-episode) conditions.

The El Nino conditions are forecast to continue through the end of 2002 and into 2003. The forecasts indicate that the El-Nino will be much weaker than the 1997-98 El-Nino. As a result the global impacts of this El-Nino may correspondingly be weaker than those observed during the stronger one of 1997-98. There is evidence that El-Nino (warm episodes) in the Pacific Ocean are liked to below average rainfall in southern Africa.

For Zambia, based on historical records of El-Nino events, southern half of Zambia is the area usually prone to drier conditions. It should be noted that this preliminary statement is entirely based on El Nino conditions, minus other global, regional and local indicators of the performance of the rainfall season. A comprehensive seasonal forecast for the coming seasonal rainfall will be issued in September 2002.