Radiocarbon dates from ice-edge ice-entombed tundra plants around the Orion and Serpens ice complexes, northern Baffin Island, Canada in 2018 and 2019

Radiocarbon dates on formerly ice-entombed tundra plants collected within 1 meter (m) of the current ice margin of rapidly receding ice caps on northern Baffin Island to test the concept of volcanic forcing on episodic ice cap expansion during the Common Era. The goal of this project is to examine the rate of onset of persistent Little Ice Age (LIA) cold by dating 50 new samples from current ice margins from ice complexes in Baffin Island, Canada, and comparing them to similar collections from 2005. If LIA ice expansion was abrupt and persistent then dates on the new plants should be about the same age as the 2005 samples, 200 to 500 m distant. Whereas if summers slowly cooled over decades-to-centuries through the late Holocene, then the new dates will be significantly older than their 2005 counterparts. Collectively, these data will provide the most robust testing of an abrupt onset of LIA cold and will be of interest to the sea ice and climate modeling communities.

本数据集包含采自巴芬岛北部快速消退冰盖当前冰缘1米（m）范围内、曾被冰封存的苔原植物的放射性碳定年（radiocarbon dating）数据，旨在检验公元纪年（Common Era）期间火山强迫驱动冰盖间歇性扩张的学术假说。本研究的核心目标为：通过对加拿大巴芬岛冰缘复合体的50个全新样品开展定年，并与2005年采集的同类样品进行对比分析，以明确小冰期（Little Ice Age, LIA）持续寒冷阶段的启动速率。若小冰期的冰盖扩张具有突发性且持续稳定，则新采集植物的定年结果应与2005年采集、距当前冰缘200至500米的样品年代相近；反之，若全新世晚期的夏季气温在数十年至数百年间持续缓慢降温，则新样品的定年结果将显著老于2005年的对应样品。综上，本数据集将为小冰期寒冷期突发性启动这一假说提供迄今最稳健的检验结果，同时可为海冰与气候模拟研究学界提供重要参考价值。