The Bible doesn’t explicitly mention the Ice Age. It wasn’t something that had much impact upon the writers of the Bible as they all lived in the Middle East, a region far south of the continental glaciations.
Scientific evidence suggests at least three historical patterns of cooling and warming, as shown by a consistent series of layers in associated rocks. The impact of glaciers and their movement is a dominant factor in the topography (land shape) of northern areas in the Americas and Europe. Despite what some might claim, however, scientists are not entirely sure why these periods would have begun or ended. This is an area where many competing theories exist, and none are especially dominant.
More importantly, none of the theories regarding an Ice Age have much to do with the Bible. Nor does the concept of an Ice Age especially prove or disprove the truth of Scripture. It’s entirely possible that rapid changes in Earth’s climate produced the effects we see. Or they may have been gradual changes. Those might have been something originating in God’s initial creation, a development over time, or the result of the flood of Noah’s day. These “ice ages” may have been much more or less dramatic than what we assume. And there are many possible explanations for what caused them to occur.
Simply put, the Bible does not say anything about an Ice Age, directly or indirectly. It’s not a topic of any special importance, and so Scripture does not address it.