Answers to such questions define the scientific information transmitted to the public, scientific community, and decision makers during the event. This assessment focused on the scientific information that appeared during the period from May 1997 to June 1998, but it also included information appearing a few months after El Niņo ended (into early 1999) since these issuances reflect the thoughts and findings being generated by scientists during the event.

The scientific issues garnering the most attention were 1) attribution of various weather events on El Niņo, 2) the relationship between El Niņo and global warming, and 3) the projected impacts expected from the climate forecasted conditions. All threee issues were filled with debate, got major media attention, and all created a confusing perspective amongst the public. This paper addresses the various viewpoints expressed on these issues and the sources of the views.