Read here. Well....the NASA scientist did not actually use the word "suck", but his description of the capabilities and problems of the models definitely leave that impression. In his own words...
We still can't predict future climate responses at low and high latitudes, which constrains our ability to forecast changes in atmospheric dynamics and regional climate.
Rind begins his review and analysis of this important subject by noting that Charney et al. (1979) concluded that global temperature sensitivity to a doubling of the atmosphere's CO2 concentration was "between 1.5° and 4.5°C," while noting that since that time "we have not moved very far from that range."
....he reports that uncertainty in our assessment of high- and low-latitude climate sensitivity "is also still as great as ever, with a factor of 2 at both high and low latitudes."
....whether the water vapor response to warming employed by climate models "is realistic is hard to assess," as he puts it, "because we have not had recent climate changes of the magnitude forecast for the rest of this century" to test it against."
Closely associated are low-latitude difficulties related to modeling both low- and high-level clouds in the tropics and the physics and dynamics associated with them, plus high-latitude difficulties associated with cryosphere feedbacks related to sea ice and snow cover.
"we can have greater confidence in the multi-model mean changes than in that of any individual model for climate change assessments." However, he says "it is doubtful that averaging different formulations together will end up giving the 'right' result," since "model responses (e.g., tropical land precipitation) can often be of different signs, and there can be little confidence that averaging them together will produce a better result."
Rind thus concludes that "at this point, we cannot determine the low- and high-latitude sensitivities, and we have no real way of obtaining them," which unknowns, in his opinion, "affect the confidence we can have in many of our projections of atmospheric dynamic and hydrologic responses to global warming."
As we have stated many times before in previous postings, climate models are basically worthless as prediction tools and should not be relied upon by policy makers for billion/trillion dollar decisions.