Ocean tides and Heinrich events

Abstract

Climate varied enormously over the most recent ice age1 — for example, large pulses of ice-rafted debris2, originating mainly from the Labrador Sea3, were deposited into the North Atlantic at roughly 7,000-year intervals, with global climatic implications3. Here we show that ocean tides within the Labrador Sea were exceptionally large over the period spanning these huge, abrupt ice movements, which are known as Heinrich events. We propose that tides played a catalytic role in liberating iceberg armadas during that time.