Study Claims Sea Ice Triggered The Little Ice Age In The 1300s

A new study has been published that has found sea ice can cause climate change. The study has found that sea ice isn't simply a passive responder to climate change. According to the study, the growth of sea ice could have contributed to the demise of Norse colonies in Greenland during the 14th and 15th centuries.The Little Ice Age trigger that cooled Europe from the 1300s through the mid-1800s arose "out of the blue" from the variability within the climate system, according to researchers. The Little Ice Age was most likely caused by the significant growth of sea ice rather than an external push from volcanic eruptions or other factors. According to the study, sudden climate changes can occur spontaneously without external forcing under the right conditions.

A comprehensive reconstruction of the sea ice showed that it was transported from the Arctic Ocean through the Fram Strait into the North Atlantic Ocean over the last 1400 years. The reconstruction suggests that the Little Ice Age is not a true Ice Age, but regional cooling centered on Europe triggered by an exceptionally large outflow of sea ice from the Arctic Ocean into the North Atlantic in the 1300s. Researchers note that previous experiments used numerical climate models and lacked physical evidence. The new study used the geological record for confirmation of model results.

Researchers used records from marine sediment cores drilled from the ocean floor in the Arctic Ocean and North Atlantic to obtain detailed information about sea ice over the last 1400 years. The cores drilled held compounds produced by algae that live in sea ice, the shells of single-celled organisms that live in different water temperatures, and debris sea ice picks up and carries over long distances.

The research team says that the core samples offered detailed enough records to detect climate changes on a decade timescale. These climate records indicate there was a significant increase in sea ice from the Arctic Ocean into the North Atlantic starting around 1300 that peaked by 1350 and ended abruptly in the late 1300s.