Arctic Sea Ice Broke up 1,400 Years Ago Holocene dynamics of the Arctic's largest ice shelf"Our findings imply that
the recent collapse of northern ice shelves cannot be considered
unprecedented, with evidence of at least some fracturing and
break-up of the coastal fringe of thick ice at ∼1.4 cal ka BP "
"The WHIS was then largely stable for three millennia until it
underwent a period of degradation at ∼1.4 cal ka BP, when it was
unable to retain freshwater for several centuries.(...)
Disraeli Fiord changes mirrored trends
in regional paleoclimate records, and together they suggest that
conditions were conducive to loss of ice-shelf integrity at this
time. Winter temperatures recorded in Greenland ice cores from
1.3–0.9 ka BP were comparable to those that caused recent iceshelf
fracturing (32) (Fig. 4F), and a period of minimum sea-ice
extent at 1.5–0.8 cal ka BP in the central Canadian Arctic
Archipelago was recorded by marine biomarker records (33)
(Fig. 4C). Moreover, driftwood delivery to northern Greenland
marked the removal of landfast sea ice at ∼1.2–0.6 ka BP (30).
Although it was suggested that this period occurred during more
than two millennia of “dramatic centennial fluctuations” in
Greenland perennial landfast ice beginning at ∼2.5 cal ka BP
(30), our data suggest only a single episode of WHIS instability
between 1.4 and 0.8 cal ka BP."
Vamos, que nos vienen a decir que en el Período Cálido Medieval la plataforma de hielo Ward Hunt también se desintegró, igual que viene ocurriendo desde hace 100 años. Y que su ruptura coincide con la misma tendencia en otros registros paleoclimáticos regionales del norte de Groenlandia o el archipiélago canadiense.
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