where we are working, in the amundsen sea, has some of the fastest changing ice.ntains them are of particular interest to scientists around the world because of this rapid change. in order to understand how the ice might behave in the future, one of the crucial pieces of information is to understand how it behaved during past times of warmer conditions. drilling kilometre—long sediment and rock cores into water thousands of metres deep is uncovering vital information. hidden within hundreds of metres of core are microscopic treasures. the continent—scale ice sheet has grown and shrunk over millions of years. but as a way to determine when that has happened, we need a time machine or a record of how it has behaved in the past. 0ur sedimentary deposits and our drill core provide that time machine. but in order to determine the exact age, we use tiny microscopic fossils made of glass, and these organisms give us a key to understanding these past records. these are known as diatoms. diatoms are photosynthetic algae that live around the world in watery environments. th