Then the particular climate sensitivity to aircraft-induced radiative forcing and aircraft signatures of climate changes may possibly be extracted. The globally averaged surface temperature change was found to be not statistically significant compared with climatic variability. The overall pattern of temperature change is statistically significant. Note that a climate sensitivity calculated for such small perturbations is associated with large uncertainty. The associated global mean surface temperature change is 0.9 K, and the RF is 1.1 W m -2 .
Internal feedback processes within and between climate models appear to work differently.
The exact nature of the climate feedback differences to different pattern of RF remains to be investigated. Thus, the climate factors of human interest, especially the regional climate change for these regional perturbations, await further development of climate models. The details of the climate response to the contrail radiative imbalance, which is spatially heterogeneous on the smallest scales, is likewise unknown.