Abstract:To solve the short-term shortage of geomagnetic second data, we study the data of Hubei inland magnetic network and find that the data of adjacent stations have high correlation and the same trend. Based on the idea of sketch, combined with the characteristics of geomagnetism, we propose a new complement strategy that uses Fourier to fit the good data with high similarity as the contour, and adjusts the Fourier parameters to make the contour fit the default data. Then we apply the ARMA prediction model to repair the details. Through processing actual default geomagnetic data, we verify that the strategy has good repair effect and provides a new idea and method for geomagnetic second data completion strategy.