My favorite place on the Healy is the bridge, where you can survey the every-changing panorama of sea ice. There’s a chair exactly like the captain’s chair, but on the port (left) side, that’s available for any member of the science team. Occupying that seat makes me feel on top of the world. which in a way I am!

During SUBICE 2014 I have a science rationale for spending time on the bridge ogling the ice. I’m privileged to participate in the cruise’s Ice Watch survey. Every two hours someone from the science party (my shift is at 22.00) takes a good look around and estimates the total extent of ice coverage, the type of ice, its thickness, the snow depth, the type of topography and a bunch of other things like the presence of sediment, algae and the preponderance of melt ponds. It may seem strange, but the ballpark figures of a bunch of human beings actually add up to a useful data set. While remote sensing (i.e. from satellites and airplanes) is valuable, it turns out to be unreliable at measuring such parameters as ice thickness. Eyeballs on the surface are key.

Ice scientist Chris Polashenski, who’s leading the Ice Watch, explains that the survey helps him understand how data he collects at one particular floe on a given day, relates to the bigger sea ice picture. Chris’s research focuses specifically on measuring ice albedo —  i.e. the ratio of reflected to incident light. Ice albedo is an important factor in climate change. Since snow-covered ice reflects a lot more sunshine back to the sky than open water, as ice extent diminishes there’s an “albedo feedback” loop. With less ice to bounce the sun’s heat back into the atmosphere, more of the sun’s energy is absorbed by the ocean, heating it up, thus in turn melting more ice.

One of the most thrilling moments in the cruise was when we got stuck in multi-year ice. As the Healy was backing and ramming into two-meter thick ice, it seemed we were making slow if uneven progress. In matter of fact, we were drifting with the floe backwards faster than were were advancing with all props running at full power.

A mix of first year and milt-year ice. The floe’s primary topography is ridges that are formed dynamically as plates collide.

The rounded topography is indicative of multi-year ice.

Nilas is newly formed surface ice. When plates are broken and collide, their sheets interlace to form finger rafting.

Closer view of Nilas finger rafting, with frost flowers adding texture to the ice surface.

Brash is broken bits of jumbled ice. Here brash is seen interspersed with small ice floes.

First year ice floe with several early stage melt ponds forming.

The chair.