Deep in Scoresby Sound, we were photographing a polar bear resting on a distant iceberg when the stillness was suddenly shattered by an immense glacier calving. Huge sections of ice broke away and crashed into the water, sending waves through the fjord and transforming the quiet Arctic landscape in seconds. As the calving continued, the polar bear reappeared and moved across the ice in search of a safer refuge. It was one of those rare moments when the scale, power and unpredictability of the Arctic became impossible to ignore.