Climatic Change

, Volume 44, Issue 4, pp 459–469

Global Warming Potentials: 2. Accuracy

  • Steven J. Smith
  • T. M. L. Wigley


This paper exposes flaws in the mathematical structure of the Global Warming Potential (GWP) concept. These lead to errors when emissions changes in different greenhouse gases are compared. The most fundamental problem is that the unit impulse response functions from which GWPs, and many of their proposed alternatives, are constructed provide an incomplete representation of the relationship between emissions and radiative forcing. Additional errors occur when GWPs are used to compare finite-length emissions changes.


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Copyright information

© Kluwer Academic Publishers 2000

Authors and Affiliations

  • Steven J. Smith
    • 1
  • T. M. L. Wigley
    • 2
  1. 1.Climate and Global Dynamics DivisionNational Center for Atmospheric ResearchBoulderU.S.A.
  2. 2.Climate and Global Dynamics DivisionNational Center for Atmospheric ResearchBoulderU.S.A.

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