Abstract We should know not only the distribution pattern of the geomagnetic field but also the distribution pattern of the geomagnetic field gradient. Based on the Gauss theory and the spherical harmonic model of the geomagnetic field, this paper has calculated the horizontal gradient (in SN and EW directi ons) and vertical gradient of the total geomagnetic intensity for China and its neighboring areas, drawn the corresponding contour map and analysed the distribution pattern of the total intensity gradient.The horizontal gradient and vertical gradient of the total geomagnetic intensity vary mainly with the latitude and have little to do with the longitude. It is worth noticing that the horizontal gradient value of the total geomagnetic intensity is highest in the central part of China.
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