The effects of ENSO are known to be far-ranging, with weather patterns affected all over the globe. With an understanding of the varying atmospheric wind patterns during ENSO events, we are interested in exploring ENSO's effects on chemical transport. In order to achieve this, we have conducted a comparative study of biomass burning in South America for two years: 1995 (during a transition from El Niņo to La Niņa) and 1997 (strong El Niņo). Locations of biomass burning were determined from the South American Automated Biomass Burning Algorithm (ABBA), which are derived from the GOES-8 satellite. Fire locations are then initialized in a forward domain filling trajectory code. We found that aerosols from biomass burning events are transported to high altitudes, including near the tropopause. The locations of aerosol transport are shown to be different for the two phases of ENSO studied. This difference should lead to varying degrees of effects on clouds by smoke aerosols.