Nonlinear Processes in Geophysics www.nonlin-processes-geophys.net 1023-5809 1607-7946 17 4 2010 10.5194/npg-17-361-2010 http://www.nonlin-processes-geophys.net/17/361/2010/ http://www.nonlin-processes-geophys.net/17/361/2010/npg-17-361-2010.html http://www.nonlin-processes-geophys.net/17/361/2010/npg-17-361-2010.pdf 361 369 2010-08-20 Image-model coupling: application to an ionospheric storm N. D. Smith n.smith@bath.ac.uk D. Pokhotelov C. N. Mitchell C. J. Budd Department of Mathematical Sciences, University of Bath, Bath, BA2 7AY, UK Department of Electronic and Electrical Engineering, University of Bath, Bath, BA2 7AY, UK Completed while with the Department of Electronic and Electrical Engineering, University of Bath, Bath, BA2 7AY, UK Techniques such as tomographic reconstruction may be used to provide images of electron content in the ionosphere. Models are also available which attempt to describe the dominant physical processes operating in the ionosphere, or the statistical relationships between ionospheric variables. It is sensible to try and couple model output to tomographic images with the aim of inferring the values of driver variables which best replicate some description of electron content imaged in the ionosphere, according to some criterion. This is a challenging task. The following describes an attempt to couple an ionospheric model to a tomographic reconstruction of the geomagnetic storm of 20 November 2003, along a latitudal line segment above north America. A simple model was chosen to reduce the number of input drivers that were varied. The investigation illustrates some of the issues involved in image-model coupling. The ability to make scientific deductions depends on the accuracy of the assumptions in the ionospheric model and the accuracy of the tomographic reconstruction. 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