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For this to succeed the size of the box and its movement direction and movement rate need to be defined. Note that the picture below is only an illustrative example for the box following the track of TC Karl and the shown box in the picture does not reflect the default values set in the model.
The track coordinates of Tropical Cyclone Karl can be obtained for instance from your Metview macros or from the US National Hurricane Center.
Namelist control of the perturbation box domain
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