Can you tell us the source of your charts. I only see one identifier, the one for GISP 2, Greenland.
We may or may not have an ice age any time soon. The Younger Dryas which actually occurred when we seemed to be in the warming phase after the last ice age was likely caused by a major boloid event in the Northern Hemisphere. It is easy to see the signficant downturn after the eruption of Toba which left crater 18 by 65 miles. There was a drop after 22,000 years ago, when Sakara-Jima (Japan) blew and left the 15 mile diameter crater. Thus I think the most likely cause of another ice age will either be a super volcano or a very major extraterrestrial impact event. Unfortunately, those are somewhat hard to predict, except to say that at some point they will happen and kill millions if not billions of people.