High Resolution Radar Profiling of the Snow and Ice Stratigraphy beneath the ITASE Traverses, West Antarctic Ice Sheet

南极西部冰盖 ITASE 横断面下方冰雪地层的高分辨率雷达剖面图

• 批准号: 0088035
• 负责人: Steven Arcone
• 金额: $ 3.32万
• 依托单位: Department of Army Cold Regions Research & Engineering Lab
• 依托单位国家: 美国
• 项目类别: Interagency Agreement
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2003-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0088035&HistoricalAwards=false
• 关键词: Resolution; Radar; Profiling; Snow; Ice

0088035 ArconeThis award supports continued acquisition of high resolution, radar reflection profiles of the snow and ice stratigraphy between core sites planned along traverse routes of the U.S. component of the InternationalTrans-Antarctic Scientific Expedition (U.S.-ITASE). The purpose is to use the profiles to establish the structure and continuity of firn stratigraphic horizons over hundreds of kilometers and to quantitativelyassess topographic and ice movement effects upon snow deposition. Other objectives are to establish the climatic extent that a single site represents and to investigate the cause of firn reflections. The radarwill also be used to identify crevasses ahead of the traverse vehicles in order to protect the safety of the scientists and support personnel on the traverse. Collaboration with other ITASE investigators will use the radar horizons as continuous isochronic references fixed by the core dating to calculate historical snow accumulation rates. The primary radar system uses 400-MHz (center frequency) short-pulse antennas, which (with processing) gives the penetration of 50-70 meters. This is the depth which is required to exceed the 200-year deposition horizon along the traverse routes. Profiles at 200 MHz will also be recorded if depths greater than 70 meters are of interest. Processing will be accomplished by data compression (stacking) to reveal long distance stratigraphic deformation, range gain corrections to give proper weight to signal amplitudes, and GPS corrections to adjust the records for the present ice sheet topography. Near surface stratigraphy will allow topographic and ice movement effects to be separated. This work is critical to the success of the U.S.-ITASE program.

0088035 Arconethis Award支持继续收购高分辨率，沿着国际反抗抗科学探险（US-ITASE）在美国的轨道途径计划的核心地点之间的降雪和冰层地层的雷达反射概况。 目的是利用剖面来建立数百公里以上FIRN地层视野的结构和连续性，并对雪沉积的定量评估地形和冰运动影响。 其他目标是确定单个站点代表并调查FIRN反射的原因的气候范围。 雷达尔维尔还可用于在横跨车辆前识别裂缝，以保护科学家的安全和横跨横越人员的支持人员。 与其他ITASE研究人员的合作将使用雷达范围作为核心日期固定的连续等速指参考，以计算历史降雪率。 主要的雷达系统使用400-MHz（中心频率）短脉冲天线，该天线（处理）的穿透性为50-70米。 这是超过沿横路线的200年沉积范围所需的深度。 如果感兴趣的深度大于70米，则还将记录200 MHz处的轮廓。 处理将通过数据压缩（堆叠）来完成，以揭示长距离地层变形，范围增长校正以给信号振幅适当的重量以及GPS校正以调整当前冰盖地形的记录。 近地面地层将使地形和冰运动效应分开。 这项工作对于美国核心计划的成功至关重要。