The world’s ice is disappearing — and with it our planet’s memory of itself.  At a very southern ribbon-cutting ceremony on the Antarctic snowpack Wednesday, scientists stored long cores of ice taken from two dying Alpine glaciers inside a 30-meter tunnel — safe, for now, from both climate change and global geopolitical upheaval. Each ice sample contains tiny microbes and bubbles of air trapped in the ancient past. Future scientists, using techniques unknown today, might use the ice cores to