Take a guess: into what category do these words fall? Frazil… Shuga… Pancake… Nilas… Brash… Bergy Bit… Hummock…
Breakfast foods? Plants? Muppets? These are actually categories of sea ice. A researcher onboard, Alice Orlich from the International Arctic Research Center (IARC) at the University Alaska Fairbanks, has spent the last 6 summers conducting sea ice observations in the Beaufort Sea of the Arctic Ocean. This season, she is instructing IARC Summer School students to observe the sea ice conditions along the NABOS cruise track. Visual shipborne sea ice observations are made from the “bridge” (where the Captain and crew drive the ship) which has the highest view of the ocean and ice cover from the ship – plus there is access to navigation information like latitude, longitude, wind speed, and ship speed. (Working on the bridge also takes some “navigating” of ship protocols – in other words, don’t get in the way of the captain, officers and crew.) Panorama photos are taken for each hourly observation to capture the ice conditions around the front of the ship, and more are taken to focus in on some features to document what’s really going on in the ice. And there can be a LOT of things going on – the World Meteorological Organization has defined 120 terms (!) in 11 categories to describe sea ice and its relation to the atmosphere and navigational issues , based on its formation, scale, age, thickness, etc. What are some of the things we have seen so far?
Nilas (thin ice, about 10 cm thick, that has formed within the current ice growth season) with “frost flowers” (the tiny white dots) forming on it. For scale, the biggest cracked piece of ice here is about 6 feet (2 meters) across.
This first year ice floe survived the recent melt season and has refrozen. This “amoeba” (not an official term, but it looks like it anyway), is about 5 feet long (less than 2 meters). It is slightly raised from the ice surrounding it (that dark color is thin, refrozen ice – not water), and the white areas are dryer ice where the water has drained from it.
This 4 foot (less than 1.5meters) thick ice was just cracked by the ship. It is first-year ice that formed at the beginning of last year’s growth season (late summer/early fall 2012), but since we are coming around to that time of year again, this would also now be known as second-year or multi-year ice. The white layer is the top, and in the bottom layer, you can see sediments that were in the ice as it formed. The blue layer is the clearest, most compressed layer.
Trick question – where is the open water in this picture? (This will be good to know if you’re ever stuck in Arctic ice.) You can tell by the “water-sky” effect. See where there is a dark layer of clouds in the distance? Those are actually areas where not as much light is being reflected back up to the clouds. So the answer to the question is: Below the water-sky.