Rethinking Media Coverage by Lisa Parks

Author:Lisa Parks
Language: eng
Format: epub
ISBN: 9781135837426
Publisher: Taylor & Francis (CAM)

The Microphysics of Geospatial Images

The struggle over the meanings and uses of geospatial images requires greater critical attention to their discursive contexts and material specificities. Geo spatial images are generated by processing data gathered by aircraft or satellites. Though aerial and satellite images involve different technologies, organizations, and companies, when they circulate in mass media culture they are often used interchangeably and without source information. US State or Defense Department officials who release these images as declassified intelligence usually offer little, if any, detail about the satellite, aircraft or sensing instruments that acquired the image-data. Captions or taglines in the press often reiterate officials’ statements or press releases and provide little information about the provenance of the image and sometimes exclude the date of its acquisition. Furthermore, as Powell’s presentation implied, it is challenging for most viewers to distinguish a satellite image from an aerial image since both look down on the earth’s surface from slightly oblique angles and rely on similar sensing instruments and imaging software. Compounding this confusion is the fact that government agencies, military units, the press, and private companies refer to aerial and satellite images in different ways. When the US State or Defense Department uses aerial or satellite images they are called reconnaissance images, and historically have also been referred to as PHOTOINT, IMAGEINT, and, more recently, GEOINT. When geographers or earth scientists use these images they are remote sensing or geospatial images. Those who want to convey that a satellite or an aircraft acquired the image-data might refer to them as satellite images or aerial images, or, more vaguely, as overhead images. The integration of aerial and satellite imaging, interactive mapping software, graphic design, and computer networking within the NGA and Google Earth has resulted in a shift away from platform-specific terminology (satellite reconnaissance) and toward the more integrative concept of geospatial imagery or intelligence or GEOINT.

This section is focused on geospatial imagery gathered by contemporary remote-sensing satellites. These satellites are equipped with instruments that can detect visible light and other frequencies of electromagnetic radiation reflected off of or emanating from objects or surfaces on earth. As Jody Berland suggests, remote sensing augments human perception by making phenomena visible that would not otherwise be perceived.41 A geospatial image in the visible light register reveals surfaces and objects on the ground as well as the sunlight or artificial light reflecting off of them, which is what makes them visible. A geospatial image in the infrared register shows surfaces and objects on the ground via the infrared or thermal radiation that they emanate. Infrared radiation has longer wavelengths than visible light and is imperceptible to the naked eye. Infrared geospatial images can show the relative temperature of objects and surfaces on or below the earth’s surface, and are also used to increase in-the-dark visibility because they reveal the contours of surfaces and objects based on their thermal radiation rather than their reflection of visible light. As a result, infrared images are often used to track and

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