The 10th Symposium on Global Change Studies

P1.30
THE EFFECT OF EL NINO ON THE TRACKS OF EXTRATROPICAL CYCLONES ACROSS NORTH AMERICA

David R. Smith, U.S. Naval Academy, Annapolis, MD; and M. J. Ledridge


The El Niño/ Southern Oscillation event has widespread effects on global atmospheric conditions. During El Niño years, it has been observed that the tracks of extratropical cyclones over the United States are altered compared to those during non-El Niño years. How cyclone tracks are affected during an El Niño event is the focus of this study. Cyclone tracks are plotted across the North American continent for the period 1 December 1997 – 31 March 1998. The frequency of occurrence and the location of the tracks during this period are compared to two other El Niño years (1982-83 and 1987-88) and two non-El Niño years (1985-86 and 1995-96). This paper examines results from both El Niño and non-El Niño cases. There appears to be an equatorward shift in the cyclone tracks during El Niño years compared to non-El Niño years, which can have a significant impact on the weather patterns of areas that are crossed (or missed) by cyclones during an El Niño year

The 10th Symposium on Global Change Studies