Nature 388, 39-44 (3 July 1997) | ; Received 27 August 1996; Accepted 29 April 1997

Evidence for human influence on climate from hemispheric temperature relations

Robert K. Kaufmann1 and David I. Stern2

  1. Center for Energy and Environmental Studies, 675 Commonwealth Avenue, Boston University, Boston, Massachusetts 02215, USA
  2. Centre for Resource and Environmental Studies, Australian National University, Canberra ACT 0200, Australia

Correspondence to: Robert K. Kaufmann1 Correspondence and requests for materials should be addressed to R.K.K. (e-mail: Email:

Analysis of observational temperature records for the Northern and Southern hemispheres indicates a statistical relationship in which Northern Hemisphere temperature depends on temperature in the Southern Hemisphere. This pattern, which has strengthened over time, can be explained by the climatic effects of anthropogenic trace gases and tropospheric sulphate aerosols. A similar statistical patternis produced by model simulations of the historical atmosphere.