Thump, Shudder, Screech

We are in the thick of winter now.  We have reached our furthest northern point, at 72 27.18 N, over the slope-basin in about 2000 m of water.  As we moved north, the ice became thicker and more resilient.  Sometimes moving is easy, sometimes we claw our way forward onto the ice, then shudder to a stop before backing down to get some space and make another run forward.    We gain speed and momentum with a great roaring of the engines and vibrating of the stern. I watch mesmerized as we move forward over the ice.  It is dark and the ice is only illuminated by the ice lights on the bow and the spotlights projecting forward.  The air is so cold that the snow is squeaky so as we move forward, with screeching noises caterwauling from under the ship.  At night when I lay in bed sometimes I think that I hear people talking, but it is only the sounds of the ice compressing under the ship and screeching past the hull.  When we back out of the ice, after grinding to a halt, the ship is often so silent while sliding through the water that I think we may not be moving.  There is something exhilarating about feeling the ship back, pause, and then pick up speed, moving forward faster and faster to crush into the ice, pushing pushing pushing until slowing and stopping. 

The view from the bridge at the end of what passes for “day”, showing the ice lights.

It has become very cold, with air temperatures below 0 F. Right now the air temperature is -14F but with even a gentle wind the wind chill is -34F.   To go out, we bundle up so much that usually no skin is even showing around the goggles, face masks, and balaklavas.  Humans become difficult to recognize, with only telltale signs such as a particular hat identifying the person.  The hands require special attention, needing occasionally to be agile and manipulate things yet also being most susceptible to the cold. Most of us have resorted to several pairs of gloves and mittens for a foray to the deck, with the pair to wear while setting up the equipment and then the pair to wear while watching the equipment in the water.  We take special care to keep the CTD warm while launching.  If it is too cold, ice will form in the tubing, sensors, and pumps once in seawater, blocking the flow of water and measurements.  We don’t even try to wash the plankton nets on deck; we just drag them into the aft hanger where there is heat and salt water and wash them down there.   The deck is covered with snow, crunchy, dry snow.  Each station is an adventure in making a hole through which to sample and then to keep the ice floes from drifting in and encroaching on the wire holding the instrument or net.  Long poles are used to push the ice floes away or, if necessary, the ship can provide a flush of water to clear the hole.

Pushing ice to maintain a hole.  The vertical line is the wire from which the CTD is hanging.

Shannon and Krista bundled up on the deck during a CTD cast.  Shannon is a Marine Science Technician in the CG and works with the science party.

Until recently, we had been traversing new or first year ice, ice that was formed this year and that is not very thick yet. But once we were reaching for our furthest north  stations, we ran into multi-year ice, ice that was formed in previous winters and that is much harder and thicker than this year’s ice.  This ice was brought from the Canadian Arctic to where we are working and is providing an adventure in icebreaking.  We expect to get out of the multiyear ice and back into this year’s ice shortly, perhaps even tomorrow.

Broken multiyear ice looking forward along the side of Healy.  The light is from the ice lights on the bow.

Despite the cold and ice, we have been collecting excellent data at all of our locations.  We have seen the plankton community transition from one typical of the shelf to one typical of the basin, with different species and plankton types found in each region.  And so we press on, through the Arctic night and cold, to see what lies under the ice.  

A map showing the locations where we have sampled in green.  Note the furthest north position.