Multi-Scale Characterization of Polar Permafrost Landscapes by Airborne and Satellite Remote Sensing and In-Situ Geophysical Measurements

在北极，在过去的几十年里观测到大气和地面的平均温度显著升高。对冻土景观的地理和生态系统的影响已经可以识别，例如灌木地的增生，或活动层厚度的增加。考虑到变化的条件对环境、人为基础设施和气候系统的影响，迫切需要确定和持续监测整个地区冰缘系统的参数。然而，由于北极地区幅员辽阔，人烟稀少，这些数据很少，而且现场收集成本高昂。在这种情况下，遥感为环境研究提供了一种有用的技术：机载和卫星成像提供了大面积表面特性的成本效益高的远程采样。我们项目的目的是确定通过遥感仪器检测到的地表特性与表征永久冻土景观状态的地下特性之间的相互联系。此外，研究结果将用于显示地表和地下相互联系的概念模型。为了实现这些目标，我们提出了一种多尺度和多传感器的方法，该方法将重点关注生态和地球系统的相互作用和尺度效应。一方面，该项目将利用(1)粗分辨率卫星光谱仪，(2)中分辨率雷达和多光谱卫星数据，(3)高分辨率激光扫描仪、热光谱和高光谱航空数据。另一方面，地下参数将通过物理地理和地球物理测量来测量：(1)现场专家测绘，(2)温度和湿度记录仪数据分析，(3)探地雷达和(4)电阻率成像。我们假设，通过成像遥感传感器捕获的地下地球物理数据和地表参数之间的关系，可以在大范围内识别、识别和量化冰缘系统不同组成部分之间的相互作用。这种全面的数据集，允许对尺度效应和生态系统相互关系进行详细的多变量统计分析，是极其罕见的。作为调查区域，我们建议麦肯齐三角洲地区和邻近的皮尔高原。这两个地区都位于加拿大西北部，在小规模上表现出不同的永久冻土主导生态系统。此外，以前收集了这两个区域的数据；现场工作数据和不同传感器的若干卫星数据可供参考。最重要的是，这个项目批准了空降行动。该特派团将由德国阿尔弗雷德-韦格纳研究所资助和执行。这架飞机将配备各种仪器，例如机载探地雷达、激光扫描仪、高光谱相机和红外辐射温度计。

In the Arctic, a significant increase of the mean air and ground temperatures has been observed during the last decades. Impacts on the geo- and ecosystem of permafrost landscapes are already recognizable - such as the proliferation of shrub lands, or the increase of the active layer thickness. Considering the consequences ofchanging conditions for the environment, for man-made infrastructure and for the climate system, there is an urgent need to determine and continuously monitor parameters of the periglacial system area-wide. However, as the Arctic is vast and poorly inhabited, such data are sparse and their in-situ collection is expensive. In this context remote sensing provides a helpful technique for environmental research: Airborne and satellite imaging delivers cost-efficient remote sampling of surface properties over large areas. The aim of our project is the identification of interconnections between surface properties detectable by remote sensing instruments and subsurface properties characterizing the state of permafrost landscapes. Further, the findings will be used to conceptual models showing the surface and sub-surface interconnections. In order to achieve these goals we propose a multi-scale and multi-sensor approach, which will focus on eco- and geosystem interactions and scaling effects. On the one hand the project will make use of (1) coarse-resolution satellite spectrometers, (2) medium-resolution radar and multispectral satellite data and (3) high-resolution laser scanner, thermal and hyperspectral airborne data. One the other hand, subsurface parameters will be measured by means of physio-geographical and geophysical surveying: (1) in-situ expert mapping, (2) analyses of temperature and moisture logger data, (3) ground penetrating radar and (4) electrical resistivity imaging. We hypothesise that the relation of subsurface geophysical data and surface parameters captured by imaging remote sensing sensors allows the area wide recognition, identification and quantification of interactions between the different components of the periglacial system. Such comprehensive datasets, which allow detailed multi-variate statistical analysis regarding scaling effects and ecosystem interconnections, are extremely rare. As investigation areas we propose the Mackenzie Delta Region and the adjacent Peel Plateau. Both regions are located in north-western Canada and exhibit different permafrost dominated ecosystems on a small scale. Further, data on both regions were previously collected; data of in-situ field work and several satellite data of different sensors are available. Above all an airborne campaign was approved for this project. This mission will be financed and conducted by the Alfred-Wegener-Institute, Germany. The aircraft will be equipped with various instruments, e.g. an airborne GPR (Ground Penetrating Radar), a laser scanner, a hyperspectral camera and an infrared radiation thermometer.