I'm dismayed trained "scientists" of today make this kind of semantic mistake, logical mistake, and utterly non-scientific assertion.
extrapolation of whatever data is always hypothetical, never fact.... yet.
The data we have clearly indicate that we do not have a factual knowledge of all that occurs at the onset of any ice age, and that what we have recorded so far in terms of "climate change" on the warm extreme is within statistical norms established in the two decades presaging ice age onsets for the past six ice ages, per the core data we do have.
"scientists" today who are onboard with the "global warming" side "climate change" hypothesis must, from the data available, be reaching that conclusion for political if not monetary (grant funding or position holding) reasons.
For whatever reasons, with the onset of each ice age, the data indicate that global temps, per sediment or ice core estimates. will plunge 10-15C within a span of fifty years from onset, after arriving at temps statistically indistinguishable from todays temps or "climate".
There is a wealth of support for these statements in the lit. Peer-reviewed lit.