INFLUENCES OF VARIOUS FORCING VARIABLES ON GLOBAL ENERGY-BALANCE DURING THE PERIOD OF INTENSIVE INSTRUMENTAL OBSERVATION (1958-1987) AND THEIR IMPLICATIONS FOR PALEOCLIMATE

Consistent, accurate, and numerous measures of global scale atmospheric variables have been collected since about 1958. A time series of 30 years duration was assembled to investigate contributing factors to the global energy balance. The El Nino-Southern Oscillation (ENSO), CO2 changes, and variation in solar energy output account for a quarter or more each of the variability in global energy balance. Upper atmospheric aerosols contribute, but less significantly and in a more complex way. The analysis suggests a hypothesis that has bearing on global climatic stability. Global climate fortuitously passed through a shift from a warmer NH to a warmer SH during the study period. The ENSO appears to act as a hemispheric energy balancing mechanism. There were significant changes in global atmospheric function when the hemispheric energy balance shifted in favor of the Southern Hemisphere about i 1966. When applied to past climates, hemispheric dominance of global climate and related patterns of periodic stability could explain the rise and fall of some complex hierarchical social systems.