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，观察到了平均气温和地面温度的显著上升。对永久冻土景观的地理和生态系统的影响已经是显而易见的--例如灌木丛的繁殖，或活动层厚度的增加。考虑到环境、人工基础设施和气候系统条件变化的后果，迫切需要确定和持续监测整个区域的冰缘系统参数。然而，由于北极幅员辽阔，居住条件恶劣，此类数据稀少，现场采集成本高昂。在这方面，遥感为环境研究提供了一种有用的技术：航空和卫星成像提供了对大面积地表特性进行成本效益高的遥感采样。我们项目的目的是查明遥感仪器可探测到的地表属性与表征永久冻土地貌状况的地下属性之间的相互联系。此外，这些发现将被用于展示表层和次表层互连的概念模型。为了实现这些目标，我们提出了一种多尺度、多传感器的方法，该方法将重点放在生态和地球系统的相互作用和尺度效应上。一方面，该项目将利用(1)高分辨率卫星光谱仪，(2)中分辨率雷达和多光谱卫星数据，以及(3)高分辨率激光扫描仪、热和高光谱航空数据。另一方面，将通过自然地理和地球物理测量来测量地下参数：(1)现场专家制图，(2)温度和湿度测井仪数据分析，(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获取的地下地球物理数据与地表参数之间的关系，可以在区域范围内识别、识别和量化冰缘系统不同组成部分之间的相互作用。如此全面的数据集，能够对规模效应和生态系统互连进行详细的多变量统计分析，是极其罕见的。作为研究区，我们提出了麦肯齐三角洲地区及其邻近的皮尔高原。这两个地区都位于加拿大西北部，在小范围内展示了不同的以永久冻土为主的生态系统。此外，以前收集了这两个区域的数据；提供了实地工作数据和不同传感器的几个卫星数据。最重要的是，这个项目批准了一次空中战役。这项任务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(GPR)、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.