Time integrated normalized difference vegetation index (ΣNDVI) derived from NOAA AVHRR multitemporal imagery over a 10-yr period (1989-1998) was used as a surrogate for primary production to investigate the impact of interannual climate variability on grassland performance for central and northern U.S. Great Plains. First, the contribution of C3 and C4 species abundances to the major grassland ecosystems of the U.S. Great Plains is described. Next, the relation between mean ΣNDVI and the ΣNDVI coefficient of variation (CV ΣNDVI) used as a proxi for interannual climate variability is analyzed. Results suggest that the differences in the long-term climatic control over ecosystem performance approximately coincide with changes between C3- and C4-dominant grassland classes. Variation in remotely sensed net primary production over time is higher for the southern and western plains grasslands (primarily C4 grasslands), whereas the C3-dominated classes in the northern and eastern portion of the U.S. Great Plains generally show lower CV ΣNDVI values.