Integrated use of field spectroscopy and satellite remote sensing for defence and security applications in Cyprus

Abstract

Underground structures can affect their surrounding landscapes in different ways such as soil moisture content, soil composition, vegetation vigour etc. The latest is often observed on the ground as a crop mark; a phenomenon which can be used as a proxy to denote the presence of underground and not visible structures. This paper presents the results obtained from field spectroradiometric campaigns at 'buried' underground structures in Cyprus. A SVC-1024 field spectroradiometer was used and in-band reflectances were determined for a variety of medium and high resolution satellite sensors as well as Landsat. A number of vegetation indices such as NDVI were obtained while a 'smart index' was developed aiming for the detection of military underground structures following the assessment of the existing vegetation indices or other available band combinations algorithm. Test areas were identified, analyzed and modeled. The areas have been analyzed and tested in different scenarios such as: (a) the 'natural state' of the underground structure (b) the different type of crop over the underground structure and imported soil (c) the different types of non-natural material over the underground structure. A reference target in the nearby area was selected. Controllable meteorological and environmental parameters were acquired and monitored. As well, an unmanned aerial vehicle (UAV) was also used to survey the area with visible and near-infrared cameras in order to generate NDVI values for comparison to the in-situ spectroradiometric measurements.