Among other things, Trenberth asserts ". . . there are no (climate) predictions by IPCC at all. And there never have been". Instead, there are only "what if" projections of future climate that correspond to certain emissions scenarios.

"None of the models used by IPCC is initialised to the observed state and none of the climate states in the models corresponds even remotely to the current observed climate.

GCMs "assume linearity" which "works for global forced variations, but it cannot work for many aspects of climate, especially those related to the water cycle . . . the science is not done because we do not have reliable or regional predictions of climate".

however, that being quoted i...

Among other things, Trenberth asserts ". . . there are no (climate) predictions by IPCC at all. And there never have been". Instead, there are only "what if" projections of future climate that correspond to certain emissions scenarios.

"None of the models used by IPCC is initialised to the observed state and none of the climate states in the models corresponds even remotely to the current observed climate.

GCMs "assume linearity" which "works for global forced variations, but it cannot work for many aspects of climate, especially those related to the water cycle . . . the science is not done because we do not have reliable or regional predictions of climate".

however, that being quoted it should be considered that despite Trenberth's statements he seems to be directly contradicted by ipcc's current presentation paper or perhaps not.