Collaborative Research: History and Evolution of the Siple Coast Ice Stream System as Recorded by Former Shear-Margin Scars

该奖项为研究南极西部简单海岸冰流系统中众所周知的疤痕状特征提供了三年的资金支持。拟议的实地工作的目的是确定几个尚未访问的疤痕的性质，并进一步表征以前确定的边缘疤痕，这些疤痕的年代很差。先进的超高分辨率辐射计（AVHRR）和Radarsat图像数据将用于定位和绘制特征，并将它们置于区域背景中。这项研究试图描述简单海岸冰川的近代史，并调查其形态变化的原因。主要的调查工具将是低频RES和高频探地雷达（GPR）剖面，用于对内层进行成像，并测量埋藏裂缝或断裂层的深度。这与由浅层冰芯确定的积累速率相结合，将为边缘特征提供“关闭”年龄。现场数据将为在活动剪切期间和关闭后的边缘和冰间流脊的冰流简单模型提供输入参数。该模型将估算出关闭时疤痕的初始高程和相应的冰流高程。

9909469ScambosThis award provides support for three years of funding to study the scar-like features that are well-known from the Siple Coast ice stream system in West Antarctica. The objective of the proposed field work is to identify the nature of several as yet unvisited scars, and to further characterize previously-identified margin scars that are poorly dated. Advanced Very High Resolution Radiometer (AVHRR) and Radarsat image data will be used to locate and map the features, and place them in a regional context. The study seeks to describe the recent history of the Siple Coast glaciers and investigate the causes of their changes in configuration. The main investigative tools will be low-frequency RES and high-frequency ground penetrating radar (GPR) profiles to image internal layers and measure depths to buried crevasses or disrupted layering. This, coupled with accumulation rates determined from shallow ice cores, will provide "shutdown" ages for the margin features. The field data will provide input parameters for simple models of ice flow for margins and inter-ice stream ridges during active shearing and after shutdown. This modeling will estimate the initial elevation of a scar at the time of shut down and the corresponding ice stream elevation at that time.