Active/Passive Microwave Remote Sensing in Application to Vegetation & Soil and Snow & Soil

通过地面表层的辐射、热量和质量通量受到雪和植被的影响。了解这些地表复盖物的状态对于陆地和大气之间的水交换特别重要。在大范围内，这种交流是一个需要考虑的驱动机制，例如，在全球气候变化情景发展中，以量化缓解战略。因此，了解有关雪和植被状况的全球信息是很重要的。进一步利用新出现的天基有源和无源传感器(雷达和辐射计)提供的远程微波信号，有可能获得有关雪和植被的信息，补充现有的相应数据产品，例如从光学传感器提供的信息。在这方面，拟议的主动/被动微波遥感在植被和土壤以及雪和土壤中的应用(MicroVegSnow)项目将支持扩大对植被覆盖和白雪覆盖地区测量的主动和被动微波数据的开发。鉴于FZJ(德国FZJ)已建立的基础设施，以及两个主办机构(FZJ和瑞士联邦森林、雪和景观研究所)在辐射传输模型、雪物理、水文学、参数估计和反演方面的专门知识，建议将MicroVegSnow作为一个联合项目。MicroVegSnow项目包括主题区域植被与土壤和雪与土壤，分别由FZJ和WSL负责。MicroVegSnow项目的总体目标是探索微波辐射传输，该辐射传输确定了包括植被和雪的足迹的远程主动和被动微波信号。为此目的，总体研究概念包括：1)对植被覆盖和白雪覆盖的足迹进行基于塔式的主动和被动微波测量，同时进行现场测量；2)开发和验证模拟相应微波信号的辐射传递正向模型；3)开发和评估从远程微波信号获取雪和植被状态信息所需的反演方案。与“植被与土壤”专题有关的微波遥感实地活动计划在2015年和2016年生长期在Jülich附近的TERENO试验场Selhausen进行。2014/15年冬季和2015/2016年冬季期间，将在达沃斯附近的一个试验场(WSL/SLF)开展相应的实地宣传活动，以支持专题领域“雪与土壤”。MicroVegSnow项目的研究成果将加深我们对主动和被动微波遥感在植被、雪和土壤中应用的理解。这是以最佳方式利用现有和未来在植被覆盖和积雪覆盖的地形上测量的微波遥感数据的基础。

Radiation, heat and mass fluxes through the terrestrial surface layer are affected by snow and vegetation. Knowing the states of these surface covers is particularly relevant with regard to the exchange of water between land and atmosphere. At the large scale, this exchange is a driving mechanism to be considered, e.g., in global climate change scenario development to quantify mitigation strategies. Accordingly, global information on snow and vegetation states are important to know. The further exploitation of remote microwave signals provided by emerging space-born active and passive sensors (radars and radiometers), bears the potential to obtain information on snow and vegetation that is complementary to corresponding existing data-products as provided, e.g., from optical sensors. In this context, the proposed project Active/Passive Microwave Remote Sensing in Application to Vegetation & Soil and Snow & Soil (MicroVegSnow) will support the extended exploitation of active and passive microwave data measured over vegetated and snow covered areas. Due to the already existing infrastructure built up at the FZJ (Forschungszentrum Jülich GmbH, Germany) and the expertise in radiative transfer modelling, snow physics, hydrology, parameter estimation and inversion available in both host institutes (FZJ and the WSL (Swiss Federal Institute for Forest, Snow and Landscape Research, Switzerland)) MicroVegSnow is proposed as a joint project. The MicroVegSnow project includes the topic areas Vegetation & Soil and Snow & Soil, which are handled by the FZJ and the WSL, respectively. The overall objective of the MicroVegSnow project is to explore the microwave radiative transfer that determines remote active and passive microwave signals of footprints comprising vegetation and snow. To this aim, the overarching research concept includes: i) tower-based active and passive microwave measurements over vegetated and snow-covered footprints accompanied by simultaneous in-situ measurements; ii) the development and the validation of radiative transfer forward models to simulate corresponding microwave signals; and iii) the development and the assessment of retrieval schemes needed to derive information on snow and vegetation states from remote microwave signals. The microwave remote sensing field campaigns associated with the topic area Vegetation & Soil are planned to be conducted at the TERENO test-site Selhausen near Jülich during the growing periods 2015 and 2016. During the winters 2014/15 and 2015/2016 corresponding field campaigns will be performed at a test-site near Davos (WSL/SLF) in support of the topic area Snow & Soil. The research outcome of the MicroVegSnow project will increase our understanding of active and passive microwave remote sensing in application to vegetation, snow, and soil. This is the basis to optimally exploit available and future microwave remote sensing data measured over vegetated and snow covered terrains.