14C (Carbon-14) ages of Holocene lake drainage events on the North Slope of Alaska, 2019-2020

Lakes are abundant features on coastal plains of the Arctic, providing important fish and wildlife habitat and water supply for villages and industry, but also interact with frozen ground (permafrost) and the carbon it stores. Most of these lakes are termed "thermokarst" because they form in ice-rich permafrost and gradually expand over time. The dynamic nature of thermokarst lakes also makes them prone to catastrophic drainage and abrupt conversion to wetlands, called drained thermokarst lake basins (DTLBs). Together, thermokarst lakes and DTLBs cover up to 80% of arctic lowland regions, making understanding their response to ongoing climate change essential for coastal plain environmental assessment. Dating the timing of lake drainage can improve our understanding of the causes and consequences of DTLB formation. This suite of 14C (Carbon-14) ages provides insight into the timing of lake drainage on the North Slope of Alaska across a range of ecosystems and surficial geology types.

北极沿海平原上湖泊广布，既是重要的鱼类与野生生物栖息地，也为村落与工业活动提供水源，同时还与永久冻土（permafrost）及其储存的碳发生相互作用。这类湖泊中多数被归类为热喀斯特湖（thermokarst lake），因其形成于富冰永久冻土中，并随时间逐步扩张。热喀斯特湖的动态特性使其极易发生灾难性排干，并快速转变为湿地，这类湿地被称为热喀斯特湖干涸盆地（drained thermokarst lake basins, DTLBs）。热喀斯特湖与热喀斯特湖干涸盆地合计覆盖了北极低地的80%区域，因此厘清它们对当前气候变化的响应，对于沿海平原的环境评估至关重要。确定湖泊排干的时间节点，有助于加深我们对热喀斯特湖干涸盆地形成的成因与影响的认识。这套14C（Carbon-14）测年数据，揭示了阿拉斯加北坡地区不同生态系统与表层地质类型下的湖泊排干时间节点。