Source: National Science Foundation Date: 2003-11-20 Volcanic Eruptions May Affect El Niño Onset A new study by scientists at the University of Virginia (UVa) in Charlottesville and the National Center for Atmospheric Research (NCAR) in Boulder, Colorado, suggests that explosive volcanic eruptions in the tropics may increase the probability of an El Niño event occurring during the winter following the eruption. The research was funded by the National Science Foundation (NSF). "The El Niño-Southern Oscillation (ENSO) is the dominant mode of interannual climate variability on the planet," says NCAR scientist Caspar Ammann. "When thinking about long-term climate, we must ask...