It claims that there were slow climate changes that happened that resulted in many cycles of ice age and then warm up, ice age, warm up.
It claims that there was a very warm time followed by One Great Ice Age. This is explained by the time leading up to Noah and the Great Flood and the Flood and then the Ice Age.
Whatever you believe, there was at least 1 ice age. There is evidence to support that. Scientists disagree with the fossils and how to date them(give them age not take them to Dinner and a movie). But, they do agree with the conditions needed for an ice age to occur: cooler summers and wetter winters with tons of snow falling. The snow would come down and never completely melt in the summer and then fall again accumulating over the past year and so forth and so on until there was an enormous amount of snow that compacted and turned to ice.. The biblical account of the world wide flood would account for those conditions as the amount of evaporation that took place would produce much more snow and rain. There is some belief(on both sides) that volcanic eruptions spewed ash into the air blocking out a lot of the light from the sun and thus causing much cooler temps. This, in turn, would cause an ice age on a global scale.
My kids and I, after studying and theorizing on it, gathered sand and dirt and pebbles and leaves and placed them in a cardboard OJ container. They filled it with water and put it in the freezer. After a few days, we took it out onto a hill in our yard. The cardboard was peeled away leaving us a glacier. We hypothesized about what would happen as our glacier moved over the earth and came to rest and began to melt. Happy learning!