Collaborative Research: Remote Observations of Ice Sheet Surface Temperature: Toward Multi-Proxy Reconstruction of Antarctic Climate Variability

合作研究：冰盖表面温度的远程观测：南极气候变化的多代理重建

• 批准号: 0126161
• 负责人: Dale Winebrenner
• 金额: $ 33.26万
• 依托单位: University of Washington
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2005-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0126161&HistoricalAwards=false
• 关键词: Collaborative; Research; Remote; Observations; Ice

This project will develop spatially extended and statistically reliable estimates of Antarctic surface temperature variations over the past several centuries, using a multi-proxy calibration/verification approach that combines the climate signal in ice core, satellite remote sensing, and weather station data. Antarctica has been problematic from the point of view of large-scale paleoclimate reconstruction because of the paucity of long-term instrumental data, and the relatively low resolution of most ice cores. Several new developments, particularly the network of shallow (~100 meter) ice cores from the ongoing International Trans-Antarctic Scientific Expedition (ITASE) project will yield broad spatial coverage of annually resolved ice core physical properties, chemistry, and stable isotope data over more than a hundred years. Second, there are now over twenty years of microwave and infrared brightness temperatures available from satellites covering virtually all of Antarctica with seasonally resolved information that has been demonstrated to record the ice surface/near surface temperature with very reasonable precision and accuracy. Finally, higher quality microwave emission data from Advanced Microwave Scanning Radiometers (AMSR) with much finer spatial resolution and radiometric fidelity than those from previous sources will offer an improved view of longer term mean temperatures in Antarctica.The 40-year instrumental record and the shorter but spatially more comprehensive Automatic Weather Station network will be combined with seasonally-resolved 37-gigahertz satellite-based ice surface temperature estimates to reconstruct Antarctic-wide temperature patterns during the past forty years. The sparser Antarctic instrumental surface temperature data available back nearly to the beginning of the century will be added for longer-term, though quite spatially-restricted, cross-validation of these reconstructions. This cross-validation procedure has been used successfully with roughly century-long instrumental records at locations primarily in the Northern Hemisphere. The longer time scale will be approached through a cross-validation of the proxy-based pre-20th century surface temperature reconstructions using information on thermal emission from deeper in the firn that is contained in low-frequency passive microwave satellite measurements. The low-frequency estimates, supplemented by borehole thermometry, will provide important independent verification of the long-term averages of the annual surfac

该项目将使用多种校准/验证方法在过去几个世纪中开发出空间扩展和统计上可靠的南极表面温度变化估计值，该方法将气候信号结合在冰芯，卫星遥感和气象站数据中。 从大规模古气候重建的角度来看，南极洲一直存在问题，因为长期仪器数据的匮乏以及大多数冰芯的分辨率相对较低。 几个新的发展，特别是来自正在进行的国际跨北极科学探险（ITASE）项目的浅层（〜100米）冰芯网络将在一百年多以上。其次，现在有二十多年的微波炉和红外亮度温度可从卫星上覆盖几乎所有南极的卫星，并具有季节性解决的信息，这些信息已被证明可记录冰面/近表面温度，其精度和准确性非常合理。 最后，与先前来源的空间分辨率和放射线延续性要高得多的高级微波扫描辐射计（AMSR）相比，高质量的微波排放数据比以前的来源具有更高的空间分辨率和放射线储备，将为南极洲的长期平均温度提供改进的长期平均温度。40年的仪器记录和空间更全面的自动级别的网络将截然不有地划分级别的坐标。在过去的四十年中，估计重建南极范围的温度模式。 几乎可以添加到本世纪初的稀疏南极仪器表面温度数据，尽管它们在空间限制的相当限制的这些重建方面都将添加到本世纪初。这种交叉验证程序已成功地用于主要在北半球的位置大约一个世纪的工具记录。使用基于20世纪前代理前的表面温度重建的交叉验证，使用有关FIRN中深层的热发射的信息进行跨验量，该信息包含在低频被动微波卫星测量中。 通过钻孔温度计补充的低频估计值将对年度Surfac的长期平均值进行重要的独立验证