or contracting, how it's flowing, whether it melts in some places, how it bust off icebergs that float away in the ocean. and we're trying to come up with some kind of a solid, reliable statement about what cities like san francisco and new york and shanghai have to plan for. >> anthony: antarctica, for all too obvious reasons, remained free of any sustained human contact until the mid-20th century when the u.s. navy launched operation deep freeze -- an enormous logistical enterprise that established the first permanent base here at mcmurdo in 1955. >> man: deep down in the ice, caves were cut, and here the supplies were packed away in a natural fridge. frozen meat, perfectly preserved, but where's that axe? let's have a bit of 15-year-old ham. >> anthony: since the national science foundation took over from the navy, things have gotten a lot less wild west around here. it feels like dorm life at college.