Impacts of the 1997-98 El Niño Event in Ecuador

At the end of March 1997, anomalous conditions were present in both the tropical Pacific Ocean and atmosphere, and during May these anomalies and their interactions confirmed the development of an El Nino-Southern Oscillation (warm) event that lasted until June 1998. Its evolution was similar to other events but its timing was different. The 1997-98 El Nino event could be catalogued as the strongest of the 20th century, surpassing the anomalies and impacts associated with the 1982-83 event. After June 1998, the ocean-atmosphere conditions reverted to average conditions, and then the opposite situation occurred with the development of a prolonged moderate La Nina (cold) event that lasted until October 2000. Information on the evolution of the 1997-98 El Nino event and its probable impacts was disseminated through different pathways within the Trade Convergence Climate Complex net (TC3) region (See Annex 1): (1) World wide web sites (http://www.cathalac.org/web-esp/new.htm) (2) Local, regional and international workshops (3) Press conferences, newspapers, interviews, reports (4) Cartoon-type literature, both on the physical aspects of the event and on its impact on socioeconomic sectors This was possible because the positive and negative impacts of previous El Nino and La Nina events had been identified prior to their most recent occurrence. The responses to the information provided within the TC3 region, which encompasses actions for impact mitigation, varied depending on the socioeconomic sector affected, on whether or not the sector was under the umbrella of a government agency, and also on the country affected. In the case of Ecuador the most important impacts are related to an increase of precipitation. Rossel (1997) established the level and limits of El Nino’s influences over the hydrologic and precipitation regimes of Ecuador, applying principal component analysis to 226 meteorological stations with over 20 years of observations. His main res