Chapter 11
Data integration Dinand Alkema Wietske Bijker Ali Sharifi Zoltan Vekerdy Wouter Verhoef 11.1
Introduction
Processes on the planet Earth are complex phenomena that are taking place in space and in time, i.e. in four dimensions. In many of these processes, differences in one dimension (e.g. height above the geoid) can be disregarded, so that two spatial dimensions and the dimension time remain. Despite this simplification, the physical description of the phenomena remains a difficult task. To better understand the processes it often helps if the same geographic region is viewed repeatedly and, if possible, also from different directions and in different wavelength regions. Integration of data from a variety of sources can be a means to retrieving information about processes that would otherwise remain undetected. Examples of important Earth system processes are: • Volcanism, earthquakes, plate tectonics • Ocean currents • Climate • Weather • The living planet (biosphere, agriculture) • Human activities (urbanization).
Data integration, as the term specifies, concerns the combination and further integration of spatial data. Such a combination may seem at a glance to be simple, but there are various important and challenging issues around it. Indeed, we have seen in earlier chapters that the combination of remote sensing data is not at all trivial. Even if the
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