Kyriacos Themistocleous

By Kyriacos Themistocleous

This chapter focuses on the development of an image-based integrated method for determining and mapping aerosol optical thickness (AOT). Using the radiative transfer (RT) equation, a methodology is developed using nonvariant targets with the revised darkest pixel method to improve the accuracy to calculate AOT over urban areas. This method can be applied to create thematic maps using GIS that present AOT values in a given area. The methodology is applied to Landsat TM/ETM+ satellite images of Limassol, Cyprus over a period of time to visualize and assess the AOT levels over the urban area. An accuracy assessment of the method shows a strong correlation between the in-situ AOT values from the sunphotometers and the AOT values derived from the image-based integrated method.

Part of the book: Aerosols

By George Melillos, Kyriacos Themistocleous, Athos Agapiou, Silas Michaelides and Diofantos Hadjimitsis

Satellite remote sensing is considered as an increasingly important technology for detecting underground structures. It can be applied to a wide range of applications, as shown by various researchers. However, there is a great need to integrate information from a variety of sources, sent at different times and of different qualities using remote sensing tools. A SVC-HR1024 field spectroradiometer could be used, and in-band reflectance’s are determined for medium- and high-resolution satellite sensors, including Landsat. Areas covered by natural soil where underground structures are present or absent can easily be detected, as a result of the change in the spectral signature of the vegetation throughout the phenological stages; in this respect, vegetation indices (VIs) such as the normalized difference vegetation index (NDVI), simple ratio (SR), and enhanced vegetation index (EVI) may be used for this purpose. Notably, the SR vegetation index is useful for determining areas where military underground structures are present.

Part of the book: Military Engineering