text: In the end the authors brand this unsolved mystery the ?Holocene temperature conundrum.? We have heard this song before, usually from climate modelers asking for more grant money to ?improve? their wonky programs. There may be some wiggle room in the interpretation of the proxy data but the new study, M13, is supposed to be the latest and most accurate temperature history available. This points directly back at the models as the weak link in the story. ?If the M13 reconstruction is correct, it will imply major biases across the current generation of climate models,? Liu et al conclude. This is more than just a conundrum for climate scientists?those computer models are the embodiment of climate science's understanding of how climate works here on planet Earth. If the models do not work, climate science has gotten it wrong.