Late spring 2021 land-fast sea ice and sub-ice platelet layer thicknesses from electromagnetic induction soundings on transect TNB-2021_NS-2_EM in Gerlache Inlet, Terra Nova Bay, Antarctica@en

Ground-based electromagnetic induction (EM) measurements of land-fast sea ice and sub-ice platelet layer (SIPL) thickness distributions were carried out on land-fast sea ice in Gerlache Inlet, Terra Nova Bay, Antarctica in late spring (November 3-7) of 2021. EM transects were carried out across Gerlache Inlet in north to south and east to west directions. The EM data were acquired using a frequency-domain Geonics Ltd EM31-MK2 instrument mounted on a sledge and towed by skidoo. The thicknesses of consolidated ice (sea ice plus the snow layer) and the SIPL were simultaneously retrieved from the EM31 measured response using the forward modelling and inversion methods of Irvin (2018).2021年春末（11月3日至7日），研究团队于南极特拉诺瓦湾（Terra Nova Bay）杰拉奇水道（Gerlache Inlet）的固定海冰区域，针对固定海冰与冰下血小板层（sub-ice platelet layer, SIPL）的厚度分布开展了地面电磁感应（electromagnetic induction, EM）测量工作。本次研究沿杰拉奇水道布设了南北向与东西向的电磁感应测线。数据采集采用Geonics Ltd生产的EM31-MK2型频域电磁仪，该仪器安装于雪橇之上，由雪地摩托牵引完成。研究人员借助Irvin（2018）提出的正演模拟与反演方法，从EM31的实测响应中同步反演得到固结冰（海冰与积雪层之和）以及冰下血小板层的厚度。