In Nova Scotia the last interglacial period was found to be older than the 30-50 ka limit of the radiocarbon dating method. In the last several decades there has been an explosion in glacier mapping studies prompted in large part by the search for mineral deposits. These have led to further refinements in the local ice model which I will summarize in a series of cartoons and descriptions. We can envision the glacial history of Maritime Canada as repeated battles for territory between land-based glaciers and the sea. During periods of climatic cooling ice sheets develop and advance, aided by the reflection of the sun's heat from the white snow surface.
Sea levels drop as ocean water is used up to make ice.
The glaciers grow, coalesce and flow all the way out to the edge of the continental shelf. There melting starts as the glaciers meet up with relatively warm ocean water. This starts the retreat process which is further accentuated as the sea-level rises, and helps to destabilize the ice sheets. Finally the rising sea and global warming win out and the glaciers are in full retreat, followed by landward-moving shorelines. The land areas, depressed by the weight of the kilometre-thick glaciers, are driven upwards as the earth rebounds.