Polar ice tracking has been described as akin to watching a very slow race. If the finishing line is an ice-free Arctic, then it's likely to be out there somewhere, although we don't know how many years it will take to reach it.
Are there any other slow races that you like to watch? I'm guessing that global temperatures, CO2 levels etc. will be commonplace here, but what else (especially things unrelated to the ice)? For me, it's disease control programmes in general, and particularly the eradication programmes vs polio and guinea worm (even though neither is now remotely important as a threat to global health since they've been pushed back so far, it'll be good to see the day when they're gone entirely). Also, the millennium development goals, and human population trends, to an extent.