I recently had occasion to learn a bit about how the Canadian Ice Service operates: tracking ice and oil slicks in the Pacific, Arctic, and Atlantic oceans. They rely on a couple of satellites – RADARSAT I and II – which are primarily synthetic aperture RADAR instruments (though they also passively observe microwave emissions from ice, which are useful for differentiating young ice from the harder multi-year sort). They also have three aircraft to cover gaps between satellite passes, as well as collect evidence of ships discharging oil, for later prosecutions. They are also the ones who put the beacon I mentioned earlier on the ice island that calved from the Petermann Glacier.
As the Arctic continues to lose old ice and summer ice, their role will only become more important. Sea traffic of all sorts is likely to increase, particularly if a trans-polar route opens up in summertime (not through either channel of the Northwest Passage, but straight across the pole) or if major oil and gas discoveries occur in the increasingly clear Arctic ocean.