When one examines the NCDC annual surface temperature anomalies
versus the NOAA estimated radiative forcing from greenhouse gasses
one finds the following relationship:
  • The cooling since 2001 ( the pause ) is real, but does not stand out from the longer term trend
  • The known exceptional years are from El Chichon, Pinatubo, and the 97/98 El Nino
  • Assuming the forcing correct and causal, this gives us an observation of the transient response (~ 1.6K)