Forces of Change
Surface temperature of the Pacific Ocean during the El Niņo of 1997-98

Surface temperature of the Pacific Ocean during the La Niņa of 1998-99

Surface temperature of the Pacific Ocean during the El Niņo of 1997-98 (top). Look for warmer temperatures (red) off the western coast of South America. Surface temperature of the Pacific Ocean during the La Niņa of 1998-99 (bottom). Look for cooler temperatures (blue) in the central Pacific. Courtesy of Cathy Smith, NOAA-CIRES, University of Colorado at Boulder