Our iceberg, B15-Y, was one of the smaller pieces and spanned a mere 20 miles of steep-edged, flat-topped ice. Large icebergs like B15 can live up to 50 years if they don’t drift into warmer waters, a decent lifespan considering the continued depredation of warmer liquid water to ice. Yet I felt an ominous sense of both the indescribable immensity and ultimate fragility of B15-Y as we sailed past, watching the waves lap at shadowed hollows at the waterline, the occasional tumble of a small ice chunk splashing down from large cracks on the blue-white ice face that extended hundreds of feet above the water. Later in the journey, every small iceberg or thick stew of partially frozen grease ice became a piece of dying B15-Y for me, all symbolic evidence of the delicate complexity of nature, and our own hand in speeding the death of such sublime natural monuments. Indeed, the Antarctic Peninsula is experiencing some of the fastest warming in the world, and to see a monolith as large as the B15 iceberg as a precursor to larger ice-sheet breakups is a sobering thought.
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Earlier that morning on our last day in Antarctica, our expedition team had fished growlers from the brash ice during a zodiac tour around a sheltered, iceberg-laden bay. Growlers are small hunks of ice of less than two meters that occur when an iceberg, or a smaller bergy-bit of between five and 15 meters, has disintegrated. Brash ice, while made up of small bergy-bits and growlers, as well as the nameless apple-sized ice chunks in a constant state of melt, is deceptively dangerous to ships in a way that massive icebergs like B15-Y are not. Because brash ice looks like a milky stew of harmless ice chunks, it can hide the sharp depths of non-tabular icebergs and the incredibly strong, dense glacial ice that can rip open a ship’s hull. Indeed, earlier in the trip our ship was blocked from the entrance of Cuverville Island by a congested floe of brash ice, forcing us to disembark elsewhere.
Yet, it was this type of brash ice that we later found ourselves up close to during our zodiac expedition, the air-filled watercraft skimming around the edges of bergy-bits and able to push small growlers out of the way with a pole. In a sheltered bay near Esperanza Station, a scientific outpost staffed by the Argentine military, we watched lazy Weddel seals sun themselves on a shared bergy-bit next to two Gentoo penguins. Our expedition leader, an Irish biologist studying southern birds, fished small chunks of clear-bubbled ice directly from the water as he worked to dislodge a sharp edged growler from beneath the propeller. He encouraged us to taste the ice, licking off the overlying salt water to find the pure, flavorless cold underneath.
“If you hold it in your bare hand long enough to speed the melting, you’ll hear it fizzle,” he told us. The fizzy pop of bergy seltzer is a familiar, yet unexpected sound. It sounds like a freshly opened can of soda, as the bubbles newly freed from the ice travel up toward the surface of the water. Yet the mundane sound of bergy seltzer belies the sinister power of melt against the bottom of the iceberg. Each bubble released scores the surface of the ice, compromising its structural integrity. We held the ice shards in our hands to make it fizz, let our skin burn against the freeze, as our expedition guide hoisted the free-floating remnants of a tiny growler into the zodiac to be chipped apart and consumed in cocktails that evening.