El Nino Will Persist into Early 2003. (Affecting Sustainable Development)

Article excerpt

The current El Nino event striking the central and eastern Equatorial Pacific basin is expected to persist into early 2003, says the World Meteorological Organization (WMO) in its latest El Nino Outlook. While it is not expected to reach the strength of the 1997-1998 event, conditions in the tropical Pacific are likely to be sufficiently anomalous to create substantial consequences in some regions.

This development calls for proactive measures to reduce vulnerability and strengthen capacity to decrease the impact of floods and droughts, as recognized in the Plan of Implementation discussed at the World Summit on Sustainable Development in Johannesburg.

Some unusual climate patterns observed recently could likely be related, at least in part, to the basin-wide El Nino that has developed in the tropical Pacific. However, the climate system functions by integrating many factors in addition to El Nino. Thus, in the case of this relatively weak episode so far, it can be difficult to attribute to it with confidence individual abnormal climate patterns or weather events that have been observed recently in the Pacific and Pacific-rim countries. This is certainly the case for several abnormal weather events that have been observed further afield.

While recent floods in China, India and Bangladesh may well be linked to the El Nino event, those in Central Europe are unlikely to have any such connection. But, they are all part of the same complex and highly variable climate system--a system which is undoubtedly changing--that governs the environment. This system is currently feeling the effects of the warmer than normal sea-surface temperatures along the equator in the central and eastern Pacific, and a tendency for climate patterns consistent with those associated with previous El Nino events can be expected.

Serious droughts are occurring in the Southern African Development Coordination (SADC) countries of southern and central Africa, resulting in starvation and a global outcry for food aid. While there has been relief in some areas, it remains unseasonably dry in others. It is unlikely that the El Nino event is playing a significant role in determining current patterns of drought and rainfall across southern Africa. But records of past El Nino events would suggest an increased probability of drier conditions across parts of southern Africa should El Nino persist into 2003, and especially if it were to intensify. Despite the intensity of the 1997-1998 El Nino, dry conditions over the region were generally averted by more favourable climate patterns prevailing at the time over the adjacent Indian Ocean. …