Icebreaking: An Exploration of the Bering Sea at the Dawn of Global Warming

By Tom Litwin, Smith College

Open water gradually filled with ice floes of all sizes, driven south by the prevailing north wind and currents. With each mile the clanging of ice against the hull increased. A thud and jolt run through the ship; a new sound, a larger piece of ice. As an open water sailor, this takes some getting use to. On the coast of Maine, this is not a good thing and a feeling typically associated with hitting a poorly charted rock at high tide. And this was just the beginning.

Gradually the floes grew denser, the time between ice collisions shorter. With floes so large the Healy is now driving into and breaking them to make progress, rather than pushing them aside as we did earlier. Still, there is plenty of open water creating a crazy quilt of dark and light shapes of every kind. There was no sun as we went below for lunch, leaving behind a dome of grey and overcast that encompassed the view in every direction. The mess hall is in the bow, just above the waterline, right next to the hull. Image a washing machine filled with rocks to get a sense of the sound accompanying lunch.

Then the sound changes again. Intermittent bangs and scrapes are replaced by a steady sound of crushing, grinding, cracking, scraping. Conversations pause until you can hear the neighbor sitting next to you. We’re now in solid ice. No breaks in the crashing, no periods of silence -- this is what we came for.

Back on the bridge and the change could not have been more pronounced. We all needed our sunglasses. Although the amount of sunlight had not changed much since going below, the seascape was no longer a checkerboard of ice and sea water, but one vast expanse of white -- snow covered ice. Without the large areas of darker seawater to absorb the sun’s energy, the ice and snow were reflecting the sun’s rays back to the atmosphere. The pre-lunch grey dome that had surrounded us was transformed, illuminated and wonderfully uplifting.

The brilliant reflection of light that greeted us brought home the concern of scientists onboard the Healy, and around the world. In summer 2007, the greatest retreat of Arctic ice in recorded history was observed. Data streaming from buoys to satellites, to scientists at the University of Washington indicate the ice cap retreat in 2008 may exceed 2007. The more dark seawater exposed, the more of the sun’s warming energy is absorbed. The more heat absorbed, the more seawater temperature rises, the faster the ice melts. Ice forms later in the fall, and retreats earlier in the spring, exposing larger areas of water, for a greater number of months, to the sun’s warming rays. Once this gets started, it will not stop. This is the problem on the researchers’ minds. But for the moment, we have a more immediate problem.

The Healy is at a dead stop, the stem nose-in to an ice pressure ridge. Although the Healy is an impressive 4 engine, 30,000 horsepower ship designed to break ice, some ice is so thick, the first ram is not enough. To make headway through this ridge -- ice floes that have collided and stacked up on each other -- the ship has to back-up, gain moment, reach a speed of 7 to 8 knots, and ram the ice. The ram does not produce the telltale crack in the ice that looks like a lightening bolt darting from the bow. The Healy again comes to a stop. The helmsman’s eyes are fixed on the impact point as he backs and rams two, then three times before the ice yields, and a crack shoots out 40 yards. We make way, but suspecting more ridges ahead, we settle in for a long night of icebreaking.

In the next installment…. A world below the ice; walking on the Bering Sea. Helicoptering to the Siberian Yupik village of Gambell on St. Lawrence Island.