The Little Ice Age may have arisen “out of the blue,” from internal variability within the climate system, rather than in response to an external push from volcanic eruptions or other factors.
A new study finds a trigger for the Little Ice Age that cooled Europe from the 1300s through mid-1800s, and supports surprising model results suggesting that under the right conditions sudden climate changes can occur spontaneously, without external forcing.
The study, published in Science Advances, reports a comprehensive reconstruction of sea ice transported from the Arctic Ocean through the Fram Strait, by Greenland, and into the North Atlantic Ocean over the last 1400 years. The reconstruction suggests that the Little Ice Age—which was not a true ice age but a regional cooling centered on Europe—was triggered by an exceptionally large outflow of sea ice from the Arctic Ocean into the North Atlantic in the 1300s.
While previous experiments using numerical climate models showed that increased sea ice was necessary to explain long-lasting climate anomalies like the Little Ice Age, physical evidence was missing. This study digs into the geological record for confirmation of model results.
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